1 /* 1 /* 2 * An async IO implementation for Linux 2 * An async IO implementation for Linux 3 * Written by Benjamin LaHaise <bcrl@kvac 3 * Written by Benjamin LaHaise <bcrl@kvack.org> 4 * 4 * 5 * Implements an efficient asynchronous i 5 * Implements an efficient asynchronous io interface. 6 * 6 * 7 * Copyright 2000, 2001, 2002 Red Hat, In 7 * Copyright 2000, 2001, 2002 Red Hat, Inc. All Rights Reserved. 8 * Copyright 2018 Christoph Hellwig. 8 * Copyright 2018 Christoph Hellwig. 9 * 9 * 10 * See ../COPYING for licensing terms. 10 * See ../COPYING for licensing terms. 11 */ 11 */ 12 #define pr_fmt(fmt) "%s: " fmt, __func__ 12 #define pr_fmt(fmt) "%s: " fmt, __func__ 13 13 14 #include <linux/kernel.h> 14 #include <linux/kernel.h> 15 #include <linux/init.h> 15 #include <linux/init.h> 16 #include <linux/errno.h> 16 #include <linux/errno.h> 17 #include <linux/time.h> 17 #include <linux/time.h> 18 #include <linux/aio_abi.h> 18 #include <linux/aio_abi.h> 19 #include <linux/export.h> 19 #include <linux/export.h> 20 #include <linux/syscalls.h> 20 #include <linux/syscalls.h> 21 #include <linux/backing-dev.h> 21 #include <linux/backing-dev.h> 22 #include <linux/refcount.h> 22 #include <linux/refcount.h> 23 #include <linux/uio.h> 23 #include <linux/uio.h> 24 24 25 #include <linux/sched/signal.h> 25 #include <linux/sched/signal.h> 26 #include <linux/fs.h> 26 #include <linux/fs.h> 27 #include <linux/file.h> 27 #include <linux/file.h> 28 #include <linux/mm.h> 28 #include <linux/mm.h> 29 #include <linux/mman.h> 29 #include <linux/mman.h> 30 #include <linux/percpu.h> 30 #include <linux/percpu.h> 31 #include <linux/slab.h> 31 #include <linux/slab.h> 32 #include <linux/timer.h> 32 #include <linux/timer.h> 33 #include <linux/aio.h> 33 #include <linux/aio.h> 34 #include <linux/highmem.h> 34 #include <linux/highmem.h> 35 #include <linux/workqueue.h> 35 #include <linux/workqueue.h> 36 #include <linux/security.h> 36 #include <linux/security.h> 37 #include <linux/eventfd.h> 37 #include <linux/eventfd.h> 38 #include <linux/blkdev.h> 38 #include <linux/blkdev.h> 39 #include <linux/compat.h> 39 #include <linux/compat.h> 40 #include <linux/migrate.h> 40 #include <linux/migrate.h> 41 #include <linux/ramfs.h> 41 #include <linux/ramfs.h> 42 #include <linux/percpu-refcount.h> 42 #include <linux/percpu-refcount.h> 43 #include <linux/mount.h> 43 #include <linux/mount.h> 44 #include <linux/pseudo_fs.h> 44 #include <linux/pseudo_fs.h> 45 45 46 #include <linux/uaccess.h> 46 #include <linux/uaccess.h> 47 #include <linux/nospec.h> 47 #include <linux/nospec.h> 48 48 49 #include "internal.h" 49 #include "internal.h" 50 50 51 #define KIOCB_KEY 0 51 #define KIOCB_KEY 0 52 52 53 #define AIO_RING_MAGIC 0xa10a 53 #define AIO_RING_MAGIC 0xa10a10a1 54 #define AIO_RING_COMPAT_FEATURES 1 54 #define AIO_RING_COMPAT_FEATURES 1 55 #define AIO_RING_INCOMPAT_FEATURES 0 55 #define AIO_RING_INCOMPAT_FEATURES 0 56 struct aio_ring { 56 struct aio_ring { 57 unsigned id; /* kernel inte 57 unsigned id; /* kernel internal index number */ 58 unsigned nr; /* number of i 58 unsigned nr; /* number of io_events */ 59 unsigned head; /* Written to 59 unsigned head; /* Written to by userland or under ring_lock 60 * mutex by ai 60 * mutex by aio_read_events_ring(). */ 61 unsigned tail; 61 unsigned tail; 62 62 63 unsigned magic; 63 unsigned magic; 64 unsigned compat_features; 64 unsigned compat_features; 65 unsigned incompat_features; 65 unsigned incompat_features; 66 unsigned header_length; /* siz 66 unsigned header_length; /* size of aio_ring */ 67 67 68 68 69 struct io_event io_events[]; 69 struct io_event io_events[]; 70 }; /* 128 bytes + ring size */ 70 }; /* 128 bytes + ring size */ 71 71 72 /* 72 /* 73 * Plugging is meant to work with larger batch 73 * Plugging is meant to work with larger batches of IOs. If we don't 74 * have more than the below, then don't bother 74 * have more than the below, then don't bother setting up a plug. 75 */ 75 */ 76 #define AIO_PLUG_THRESHOLD 2 76 #define AIO_PLUG_THRESHOLD 2 77 77 78 #define AIO_RING_PAGES 8 78 #define AIO_RING_PAGES 8 79 79 80 struct kioctx_table { 80 struct kioctx_table { 81 struct rcu_head rcu; 81 struct rcu_head rcu; 82 unsigned nr; 82 unsigned nr; 83 struct kioctx __rcu *table[] __cou !! 83 struct kioctx __rcu *table[]; 84 }; 84 }; 85 85 86 struct kioctx_cpu { 86 struct kioctx_cpu { 87 unsigned reqs_available 87 unsigned reqs_available; 88 }; 88 }; 89 89 90 struct ctx_rq_wait { 90 struct ctx_rq_wait { 91 struct completion comp; 91 struct completion comp; 92 atomic_t count; 92 atomic_t count; 93 }; 93 }; 94 94 95 struct kioctx { 95 struct kioctx { 96 struct percpu_ref users; 96 struct percpu_ref users; 97 atomic_t dead; 97 atomic_t dead; 98 98 99 struct percpu_ref reqs; 99 struct percpu_ref reqs; 100 100 101 unsigned long user_id; 101 unsigned long user_id; 102 102 103 struct kioctx_cpu __percpu *cpu; !! 103 struct __percpu kioctx_cpu *cpu; 104 104 105 /* 105 /* 106 * For percpu reqs_available, number o 106 * For percpu reqs_available, number of slots we move to/from global 107 * counter at a time: 107 * counter at a time: 108 */ 108 */ 109 unsigned req_batch; 109 unsigned req_batch; 110 /* 110 /* 111 * This is what userspace passed to io 111 * This is what userspace passed to io_setup(), it's not used for 112 * anything but counting against the g 112 * anything but counting against the global max_reqs quota. 113 * 113 * 114 * The real limit is nr_events - 1, wh 114 * The real limit is nr_events - 1, which will be larger (see 115 * aio_setup_ring()) 115 * aio_setup_ring()) 116 */ 116 */ 117 unsigned max_reqs; 117 unsigned max_reqs; 118 118 119 /* Size of ringbuffer, in units of str 119 /* Size of ringbuffer, in units of struct io_event */ 120 unsigned nr_events; 120 unsigned nr_events; 121 121 122 unsigned long mmap_base; 122 unsigned long mmap_base; 123 unsigned long mmap_size; 123 unsigned long mmap_size; 124 124 125 struct folio **ring_folios; !! 125 struct page **ring_pages; 126 long nr_pages; 126 long nr_pages; 127 127 128 struct rcu_work free_rwork; 128 struct rcu_work free_rwork; /* see free_ioctx() */ 129 129 130 /* 130 /* 131 * signals when all in-flight requests 131 * signals when all in-flight requests are done 132 */ 132 */ 133 struct ctx_rq_wait *rq_wait; 133 struct ctx_rq_wait *rq_wait; 134 134 135 struct { 135 struct { 136 /* 136 /* 137 * This counts the number of a 137 * This counts the number of available slots in the ringbuffer, 138 * so we avoid overflowing it: 138 * so we avoid overflowing it: it's decremented (if positive) 139 * when allocating a kiocb and 139 * when allocating a kiocb and incremented when the resulting 140 * io_event is pulled off the 140 * io_event is pulled off the ringbuffer. 141 * 141 * 142 * We batch accesses to it wit 142 * We batch accesses to it with a percpu version. 143 */ 143 */ 144 atomic_t reqs_available 144 atomic_t reqs_available; 145 } ____cacheline_aligned_in_smp; 145 } ____cacheline_aligned_in_smp; 146 146 147 struct { 147 struct { 148 spinlock_t ctx_lock; 148 spinlock_t ctx_lock; 149 struct list_head active_reqs; 149 struct list_head active_reqs; /* used for cancellation */ 150 } ____cacheline_aligned_in_smp; 150 } ____cacheline_aligned_in_smp; 151 151 152 struct { 152 struct { 153 struct mutex ring_lock; 153 struct mutex ring_lock; 154 wait_queue_head_t wait; 154 wait_queue_head_t wait; 155 } ____cacheline_aligned_in_smp; 155 } ____cacheline_aligned_in_smp; 156 156 157 struct { 157 struct { 158 unsigned tail; 158 unsigned tail; 159 unsigned completed_even 159 unsigned completed_events; 160 spinlock_t completion_loc 160 spinlock_t completion_lock; 161 } ____cacheline_aligned_in_smp; 161 } ____cacheline_aligned_in_smp; 162 162 163 struct folio *internal_foli !! 163 struct page *internal_pages[AIO_RING_PAGES]; 164 struct file *aio_ring_file 164 struct file *aio_ring_file; 165 165 166 unsigned id; 166 unsigned id; 167 }; 167 }; 168 168 169 /* 169 /* 170 * First field must be the file pointer in all 170 * First field must be the file pointer in all the 171 * iocb unions! See also 'struct kiocb' in <li 171 * iocb unions! See also 'struct kiocb' in <linux/fs.h> 172 */ 172 */ 173 struct fsync_iocb { 173 struct fsync_iocb { 174 struct file *file; 174 struct file *file; 175 struct work_struct work; 175 struct work_struct work; 176 bool datasync; 176 bool datasync; 177 struct cred *creds; 177 struct cred *creds; 178 }; 178 }; 179 179 180 struct poll_iocb { 180 struct poll_iocb { 181 struct file *file; 181 struct file *file; 182 struct wait_queue_head *head; 182 struct wait_queue_head *head; 183 __poll_t events; 183 __poll_t events; >> 184 bool done; 184 bool cancelled; 185 bool cancelled; 185 bool work_scheduled << 186 bool work_need_resc << 187 struct wait_queue_entry wait; 186 struct wait_queue_entry wait; 188 struct work_struct work; 187 struct work_struct work; 189 }; 188 }; 190 189 191 /* 190 /* 192 * NOTE! Each of the iocb union members has th 191 * NOTE! Each of the iocb union members has the file pointer 193 * as the first entry in their struct definiti 192 * as the first entry in their struct definition. So you can 194 * access the file pointer through any of the 193 * access the file pointer through any of the sub-structs, 195 * or directly as just 'ki_filp' in this struc 194 * or directly as just 'ki_filp' in this struct. 196 */ 195 */ 197 struct aio_kiocb { 196 struct aio_kiocb { 198 union { 197 union { 199 struct file *ki_fi 198 struct file *ki_filp; 200 struct kiocb rw; 199 struct kiocb rw; 201 struct fsync_iocb fsync; 200 struct fsync_iocb fsync; 202 struct poll_iocb poll; 201 struct poll_iocb poll; 203 }; 202 }; 204 203 205 struct kioctx *ki_ctx; 204 struct kioctx *ki_ctx; 206 kiocb_cancel_fn *ki_cancel; 205 kiocb_cancel_fn *ki_cancel; 207 206 208 struct io_event ki_res; 207 struct io_event ki_res; 209 208 210 struct list_head ki_list; 209 struct list_head ki_list; /* the aio core uses this 211 210 * for cancellation */ 212 refcount_t ki_refcnt; 211 refcount_t ki_refcnt; 213 212 214 /* 213 /* 215 * If the aio_resfd field of the users 214 * If the aio_resfd field of the userspace iocb is not zero, 216 * this is the underlying eventfd cont 215 * this is the underlying eventfd context to deliver events to. 217 */ 216 */ 218 struct eventfd_ctx *ki_eventfd; 217 struct eventfd_ctx *ki_eventfd; 219 }; 218 }; 220 219 221 /*------ sysctl variables----*/ 220 /*------ sysctl variables----*/ 222 static DEFINE_SPINLOCK(aio_nr_lock); 221 static DEFINE_SPINLOCK(aio_nr_lock); 223 static unsigned long aio_nr; /* cur !! 222 unsigned long aio_nr; /* current system wide number of aio requests */ 224 static unsigned long aio_max_nr = 0x10000; /* !! 223 unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio requests */ 225 /*----end sysctl variables---*/ 224 /*----end sysctl variables---*/ 226 #ifdef CONFIG_SYSCTL << 227 static struct ctl_table aio_sysctls[] = { << 228 { << 229 .procname = "aio-nr", << 230 .data = &aio_nr, << 231 .maxlen = sizeof(aio_n << 232 .mode = 0444, << 233 .proc_handler = proc_doulong << 234 }, << 235 { << 236 .procname = "aio-max-nr" << 237 .data = &aio_max_nr, << 238 .maxlen = sizeof(aio_m << 239 .mode = 0644, << 240 .proc_handler = proc_doulong << 241 }, << 242 }; << 243 << 244 static void __init aio_sysctl_init(void) << 245 { << 246 register_sysctl_init("fs", aio_sysctls << 247 } << 248 #else << 249 #define aio_sysctl_init() do { } while (0) << 250 #endif << 251 225 252 static struct kmem_cache *kiocb_cachep; 226 static struct kmem_cache *kiocb_cachep; 253 static struct kmem_cache *kioctx_cachep 227 static struct kmem_cache *kioctx_cachep; 254 228 255 static struct vfsmount *aio_mnt; 229 static struct vfsmount *aio_mnt; 256 230 257 static const struct file_operations aio_ring_f 231 static const struct file_operations aio_ring_fops; 258 static const struct address_space_operations a 232 static const struct address_space_operations aio_ctx_aops; 259 233 260 static struct file *aio_private_file(struct ki 234 static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages) 261 { 235 { 262 struct file *file; 236 struct file *file; 263 struct inode *inode = alloc_anon_inode 237 struct inode *inode = alloc_anon_inode(aio_mnt->mnt_sb); 264 if (IS_ERR(inode)) 238 if (IS_ERR(inode)) 265 return ERR_CAST(inode); 239 return ERR_CAST(inode); 266 240 267 inode->i_mapping->a_ops = &aio_ctx_aop 241 inode->i_mapping->a_ops = &aio_ctx_aops; 268 inode->i_mapping->i_private_data = ctx !! 242 inode->i_mapping->private_data = ctx; 269 inode->i_size = PAGE_SIZE * nr_pages; 243 inode->i_size = PAGE_SIZE * nr_pages; 270 244 271 file = alloc_file_pseudo(inode, aio_mn 245 file = alloc_file_pseudo(inode, aio_mnt, "[aio]", 272 O_RDWR, &aio_r 246 O_RDWR, &aio_ring_fops); 273 if (IS_ERR(file)) 247 if (IS_ERR(file)) 274 iput(inode); 248 iput(inode); 275 return file; 249 return file; 276 } 250 } 277 251 278 static int aio_init_fs_context(struct fs_conte 252 static int aio_init_fs_context(struct fs_context *fc) 279 { 253 { 280 if (!init_pseudo(fc, AIO_RING_MAGIC)) 254 if (!init_pseudo(fc, AIO_RING_MAGIC)) 281 return -ENOMEM; 255 return -ENOMEM; 282 fc->s_iflags |= SB_I_NOEXEC; 256 fc->s_iflags |= SB_I_NOEXEC; 283 return 0; 257 return 0; 284 } 258 } 285 259 286 /* aio_setup 260 /* aio_setup 287 * Creates the slab caches used by the ai 261 * Creates the slab caches used by the aio routines, panic on 288 * failure as this is done early during t 262 * failure as this is done early during the boot sequence. 289 */ 263 */ 290 static int __init aio_setup(void) 264 static int __init aio_setup(void) 291 { 265 { 292 static struct file_system_type aio_fs 266 static struct file_system_type aio_fs = { 293 .name = "aio", 267 .name = "aio", 294 .init_fs_context = aio_init_fs 268 .init_fs_context = aio_init_fs_context, 295 .kill_sb = kill_anon_su 269 .kill_sb = kill_anon_super, 296 }; 270 }; 297 aio_mnt = kern_mount(&aio_fs); 271 aio_mnt = kern_mount(&aio_fs); 298 if (IS_ERR(aio_mnt)) 272 if (IS_ERR(aio_mnt)) 299 panic("Failed to create aio fs 273 panic("Failed to create aio fs mount."); 300 274 301 kiocb_cachep = KMEM_CACHE(aio_kiocb, S 275 kiocb_cachep = KMEM_CACHE(aio_kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC); 302 kioctx_cachep = KMEM_CACHE(kioctx,SLAB 276 kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC); 303 aio_sysctl_init(); << 304 return 0; 277 return 0; 305 } 278 } 306 __initcall(aio_setup); 279 __initcall(aio_setup); 307 280 308 static void put_aio_ring_file(struct kioctx *c 281 static void put_aio_ring_file(struct kioctx *ctx) 309 { 282 { 310 struct file *aio_ring_file = ctx->aio_ 283 struct file *aio_ring_file = ctx->aio_ring_file; 311 struct address_space *i_mapping; 284 struct address_space *i_mapping; 312 285 313 if (aio_ring_file) { 286 if (aio_ring_file) { 314 truncate_setsize(file_inode(ai 287 truncate_setsize(file_inode(aio_ring_file), 0); 315 288 316 /* Prevent further access to t 289 /* Prevent further access to the kioctx from migratepages */ 317 i_mapping = aio_ring_file->f_m 290 i_mapping = aio_ring_file->f_mapping; 318 spin_lock(&i_mapping->i_privat !! 291 spin_lock(&i_mapping->private_lock); 319 i_mapping->i_private_data = NU !! 292 i_mapping->private_data = NULL; 320 ctx->aio_ring_file = NULL; 293 ctx->aio_ring_file = NULL; 321 spin_unlock(&i_mapping->i_priv !! 294 spin_unlock(&i_mapping->private_lock); 322 295 323 fput(aio_ring_file); 296 fput(aio_ring_file); 324 } 297 } 325 } 298 } 326 299 327 static void aio_free_ring(struct kioctx *ctx) 300 static void aio_free_ring(struct kioctx *ctx) 328 { 301 { 329 int i; 302 int i; 330 303 331 /* Disconnect the kiotx from the ring 304 /* Disconnect the kiotx from the ring file. This prevents future 332 * accesses to the kioctx from page mi 305 * accesses to the kioctx from page migration. 333 */ 306 */ 334 put_aio_ring_file(ctx); 307 put_aio_ring_file(ctx); 335 308 336 for (i = 0; i < ctx->nr_pages; i++) { 309 for (i = 0; i < ctx->nr_pages; i++) { 337 struct folio *folio = ctx->rin !! 310 struct page *page; 338 !! 311 pr_debug("pid(%d) [%d] page->count=%d\n", current->pid, i, 339 if (!folio) !! 312 page_count(ctx->ring_pages[i])); >> 313 page = ctx->ring_pages[i]; >> 314 if (!page) 340 continue; 315 continue; 341 !! 316 ctx->ring_pages[i] = NULL; 342 pr_debug("pid(%d) [%d] folio-> !! 317 put_page(page); 343 folio_ref_count(folio << 344 ctx->ring_folios[i] = NULL; << 345 folio_put(folio); << 346 } 318 } 347 319 348 if (ctx->ring_folios && ctx->ring_foli !! 320 if (ctx->ring_pages && ctx->ring_pages != ctx->internal_pages) { 349 kfree(ctx->ring_folios); !! 321 kfree(ctx->ring_pages); 350 ctx->ring_folios = NULL; !! 322 ctx->ring_pages = NULL; 351 } 323 } 352 } 324 } 353 325 354 static int aio_ring_mremap(struct vm_area_stru 326 static int aio_ring_mremap(struct vm_area_struct *vma) 355 { 327 { 356 struct file *file = vma->vm_file; 328 struct file *file = vma->vm_file; 357 struct mm_struct *mm = vma->vm_mm; 329 struct mm_struct *mm = vma->vm_mm; 358 struct kioctx_table *table; 330 struct kioctx_table *table; 359 int i, res = -EINVAL; 331 int i, res = -EINVAL; 360 332 361 spin_lock(&mm->ioctx_lock); 333 spin_lock(&mm->ioctx_lock); 362 rcu_read_lock(); 334 rcu_read_lock(); 363 table = rcu_dereference(mm->ioctx_tabl 335 table = rcu_dereference(mm->ioctx_table); 364 if (!table) << 365 goto out_unlock; << 366 << 367 for (i = 0; i < table->nr; i++) { 336 for (i = 0; i < table->nr; i++) { 368 struct kioctx *ctx; 337 struct kioctx *ctx; 369 338 370 ctx = rcu_dereference(table->t 339 ctx = rcu_dereference(table->table[i]); 371 if (ctx && ctx->aio_ring_file 340 if (ctx && ctx->aio_ring_file == file) { 372 if (!atomic_read(&ctx- 341 if (!atomic_read(&ctx->dead)) { 373 ctx->user_id = 342 ctx->user_id = ctx->mmap_base = vma->vm_start; 374 res = 0; 343 res = 0; 375 } 344 } 376 break; 345 break; 377 } 346 } 378 } 347 } 379 348 380 out_unlock: << 381 rcu_read_unlock(); 349 rcu_read_unlock(); 382 spin_unlock(&mm->ioctx_lock); 350 spin_unlock(&mm->ioctx_lock); 383 return res; 351 return res; 384 } 352 } 385 353 386 static const struct vm_operations_struct aio_r 354 static const struct vm_operations_struct aio_ring_vm_ops = { 387 .mremap = aio_ring_mremap, 355 .mremap = aio_ring_mremap, 388 #if IS_ENABLED(CONFIG_MMU) 356 #if IS_ENABLED(CONFIG_MMU) 389 .fault = filemap_fault, 357 .fault = filemap_fault, 390 .map_pages = filemap_map_pages, 358 .map_pages = filemap_map_pages, 391 .page_mkwrite = filemap_page_mkwrite 359 .page_mkwrite = filemap_page_mkwrite, 392 #endif 360 #endif 393 }; 361 }; 394 362 395 static int aio_ring_mmap(struct file *file, st 363 static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma) 396 { 364 { 397 vm_flags_set(vma, VM_DONTEXPAND); !! 365 vma->vm_flags |= VM_DONTEXPAND; 398 vma->vm_ops = &aio_ring_vm_ops; 366 vma->vm_ops = &aio_ring_vm_ops; 399 return 0; 367 return 0; 400 } 368 } 401 369 402 static const struct file_operations aio_ring_f 370 static const struct file_operations aio_ring_fops = { 403 .mmap = aio_ring_mmap, 371 .mmap = aio_ring_mmap, 404 }; 372 }; 405 373 406 #if IS_ENABLED(CONFIG_MIGRATION) 374 #if IS_ENABLED(CONFIG_MIGRATION) 407 static int aio_migrate_folio(struct address_sp !! 375 static int aio_migratepage(struct address_space *mapping, struct page *new, 408 struct folio *src, enu !! 376 struct page *old, enum migrate_mode mode) 409 { 377 { 410 struct kioctx *ctx; 378 struct kioctx *ctx; 411 unsigned long flags; 379 unsigned long flags; 412 pgoff_t idx; 380 pgoff_t idx; 413 int rc = 0; !! 381 int rc; >> 382 >> 383 /* >> 384 * We cannot support the _NO_COPY case here, because copy needs to >> 385 * happen under the ctx->completion_lock. That does not work with the >> 386 * migration workflow of MIGRATE_SYNC_NO_COPY. >> 387 */ >> 388 if (mode == MIGRATE_SYNC_NO_COPY) >> 389 return -EINVAL; 414 390 415 /* mapping->i_private_lock here protec !! 391 rc = 0; 416 spin_lock(&mapping->i_private_lock); !! 392 417 ctx = mapping->i_private_data; !! 393 /* mapping->private_lock here protects against the kioctx teardown. */ >> 394 spin_lock(&mapping->private_lock); >> 395 ctx = mapping->private_data; 418 if (!ctx) { 396 if (!ctx) { 419 rc = -EINVAL; 397 rc = -EINVAL; 420 goto out; 398 goto out; 421 } 399 } 422 400 423 /* The ring_lock mutex. The prevents 401 /* The ring_lock mutex. The prevents aio_read_events() from writing 424 * to the ring's head, and prevents pa 402 * to the ring's head, and prevents page migration from mucking in 425 * a partially initialized kiotx. 403 * a partially initialized kiotx. 426 */ 404 */ 427 if (!mutex_trylock(&ctx->ring_lock)) { 405 if (!mutex_trylock(&ctx->ring_lock)) { 428 rc = -EAGAIN; 406 rc = -EAGAIN; 429 goto out; 407 goto out; 430 } 408 } 431 409 432 idx = src->index; !! 410 idx = old->index; 433 if (idx < (pgoff_t)ctx->nr_pages) { 411 if (idx < (pgoff_t)ctx->nr_pages) { 434 /* Make sure the old folio has !! 412 /* Make sure the old page hasn't already been changed */ 435 if (ctx->ring_folios[idx] != s !! 413 if (ctx->ring_pages[idx] != old) 436 rc = -EAGAIN; 414 rc = -EAGAIN; 437 } else 415 } else 438 rc = -EINVAL; 416 rc = -EINVAL; 439 417 440 if (rc != 0) 418 if (rc != 0) 441 goto out_unlock; 419 goto out_unlock; 442 420 443 /* Writeback must be complete */ 421 /* Writeback must be complete */ 444 BUG_ON(folio_test_writeback(src)); !! 422 BUG_ON(PageWriteback(old)); 445 folio_get(dst); !! 423 get_page(new); 446 424 447 rc = folio_migrate_mapping(mapping, ds !! 425 rc = migrate_page_move_mapping(mapping, new, old, 1); 448 if (rc != MIGRATEPAGE_SUCCESS) { 426 if (rc != MIGRATEPAGE_SUCCESS) { 449 folio_put(dst); !! 427 put_page(new); 450 goto out_unlock; 428 goto out_unlock; 451 } 429 } 452 430 453 /* Take completion_lock to prevent oth 431 /* Take completion_lock to prevent other writes to the ring buffer 454 * while the old folio is copied to th !! 432 * while the old page is copied to the new. This prevents new 455 * events from being lost. 433 * events from being lost. 456 */ 434 */ 457 spin_lock_irqsave(&ctx->completion_loc 435 spin_lock_irqsave(&ctx->completion_lock, flags); 458 folio_copy(dst, src); !! 436 migrate_page_copy(new, old); 459 folio_migrate_flags(dst, src); !! 437 BUG_ON(ctx->ring_pages[idx] != old); 460 BUG_ON(ctx->ring_folios[idx] != src); !! 438 ctx->ring_pages[idx] = new; 461 ctx->ring_folios[idx] = dst; << 462 spin_unlock_irqrestore(&ctx->completio 439 spin_unlock_irqrestore(&ctx->completion_lock, flags); 463 440 464 /* The old folio is no longer accessib !! 441 /* The old page is no longer accessible. */ 465 folio_put(src); !! 442 put_page(old); 466 443 467 out_unlock: 444 out_unlock: 468 mutex_unlock(&ctx->ring_lock); 445 mutex_unlock(&ctx->ring_lock); 469 out: 446 out: 470 spin_unlock(&mapping->i_private_lock); !! 447 spin_unlock(&mapping->private_lock); 471 return rc; 448 return rc; 472 } 449 } 473 #else << 474 #define aio_migrate_folio NULL << 475 #endif 450 #endif 476 451 477 static const struct address_space_operations a 452 static const struct address_space_operations aio_ctx_aops = { 478 .dirty_folio = noop_dirty_folio, !! 453 .set_page_dirty = __set_page_dirty_no_writeback, 479 .migrate_folio = aio_migrate_folio, !! 454 #if IS_ENABLED(CONFIG_MIGRATION) >> 455 .migratepage = aio_migratepage, >> 456 #endif 480 }; 457 }; 481 458 482 static int aio_setup_ring(struct kioctx *ctx, 459 static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events) 483 { 460 { 484 struct aio_ring *ring; 461 struct aio_ring *ring; 485 struct mm_struct *mm = current->mm; 462 struct mm_struct *mm = current->mm; 486 unsigned long size, unused; 463 unsigned long size, unused; 487 int nr_pages; 464 int nr_pages; 488 int i; 465 int i; 489 struct file *file; 466 struct file *file; 490 467 491 /* Compensate for the ring buffer's he 468 /* Compensate for the ring buffer's head/tail overlap entry */ 492 nr_events += 2; /* 1 is required, 2 fo 469 nr_events += 2; /* 1 is required, 2 for good luck */ 493 470 494 size = sizeof(struct aio_ring); 471 size = sizeof(struct aio_ring); 495 size += sizeof(struct io_event) * nr_e 472 size += sizeof(struct io_event) * nr_events; 496 473 497 nr_pages = PFN_UP(size); 474 nr_pages = PFN_UP(size); 498 if (nr_pages < 0) 475 if (nr_pages < 0) 499 return -EINVAL; 476 return -EINVAL; 500 477 501 file = aio_private_file(ctx, nr_pages) 478 file = aio_private_file(ctx, nr_pages); 502 if (IS_ERR(file)) { 479 if (IS_ERR(file)) { 503 ctx->aio_ring_file = NULL; 480 ctx->aio_ring_file = NULL; 504 return -ENOMEM; 481 return -ENOMEM; 505 } 482 } 506 483 507 ctx->aio_ring_file = file; 484 ctx->aio_ring_file = file; 508 nr_events = (PAGE_SIZE * nr_pages - si 485 nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring)) 509 / sizeof(struct io_eve 486 / sizeof(struct io_event); 510 487 511 ctx->ring_folios = ctx->internal_folio !! 488 ctx->ring_pages = ctx->internal_pages; 512 if (nr_pages > AIO_RING_PAGES) { 489 if (nr_pages > AIO_RING_PAGES) { 513 ctx->ring_folios = kcalloc(nr_ !! 490 ctx->ring_pages = kcalloc(nr_pages, sizeof(struct page *), 514 GFP !! 491 GFP_KERNEL); 515 if (!ctx->ring_folios) { !! 492 if (!ctx->ring_pages) { 516 put_aio_ring_file(ctx) 493 put_aio_ring_file(ctx); 517 return -ENOMEM; 494 return -ENOMEM; 518 } 495 } 519 } 496 } 520 497 521 for (i = 0; i < nr_pages; i++) { 498 for (i = 0; i < nr_pages; i++) { 522 struct folio *folio; !! 499 struct page *page; 523 !! 500 page = find_or_create_page(file->f_mapping, 524 folio = __filemap_get_folio(fi !! 501 i, GFP_HIGHUSER | __GFP_ZERO); 525 FG !! 502 if (!page) 526 GF << 527 if (IS_ERR(folio)) << 528 break; 503 break; >> 504 pr_debug("pid(%d) page[%d]->count=%d\n", >> 505 current->pid, i, page_count(page)); >> 506 SetPageUptodate(page); >> 507 unlock_page(page); 529 508 530 pr_debug("pid(%d) [%d] folio-> !! 509 ctx->ring_pages[i] = page; 531 folio_ref_count(folio << 532 folio_end_read(folio, true); << 533 << 534 ctx->ring_folios[i] = folio; << 535 } 510 } 536 ctx->nr_pages = i; 511 ctx->nr_pages = i; 537 512 538 if (unlikely(i != nr_pages)) { 513 if (unlikely(i != nr_pages)) { 539 aio_free_ring(ctx); 514 aio_free_ring(ctx); 540 return -ENOMEM; 515 return -ENOMEM; 541 } 516 } 542 517 543 ctx->mmap_size = nr_pages * PAGE_SIZE; 518 ctx->mmap_size = nr_pages * PAGE_SIZE; 544 pr_debug("attempting mmap of %lu bytes 519 pr_debug("attempting mmap of %lu bytes\n", ctx->mmap_size); 545 520 546 if (mmap_write_lock_killable(mm)) { 521 if (mmap_write_lock_killable(mm)) { 547 ctx->mmap_size = 0; 522 ctx->mmap_size = 0; 548 aio_free_ring(ctx); 523 aio_free_ring(ctx); 549 return -EINTR; 524 return -EINTR; 550 } 525 } 551 526 552 ctx->mmap_base = do_mmap(ctx->aio_ring 527 ctx->mmap_base = do_mmap(ctx->aio_ring_file, 0, ctx->mmap_size, 553 PROT_READ | P 528 PROT_READ | PROT_WRITE, 554 MAP_SHARED, 0 !! 529 MAP_SHARED, 0, &unused, NULL); 555 mmap_write_unlock(mm); 530 mmap_write_unlock(mm); 556 if (IS_ERR((void *)ctx->mmap_base)) { 531 if (IS_ERR((void *)ctx->mmap_base)) { 557 ctx->mmap_size = 0; 532 ctx->mmap_size = 0; 558 aio_free_ring(ctx); 533 aio_free_ring(ctx); 559 return -ENOMEM; 534 return -ENOMEM; 560 } 535 } 561 536 562 pr_debug("mmap address: 0x%08lx\n", ct 537 pr_debug("mmap address: 0x%08lx\n", ctx->mmap_base); 563 538 564 ctx->user_id = ctx->mmap_base; 539 ctx->user_id = ctx->mmap_base; 565 ctx->nr_events = nr_events; /* trusted 540 ctx->nr_events = nr_events; /* trusted copy */ 566 541 567 ring = folio_address(ctx->ring_folios[ !! 542 ring = kmap_atomic(ctx->ring_pages[0]); 568 ring->nr = nr_events; /* user copy * 543 ring->nr = nr_events; /* user copy */ 569 ring->id = ~0U; 544 ring->id = ~0U; 570 ring->head = ring->tail = 0; 545 ring->head = ring->tail = 0; 571 ring->magic = AIO_RING_MAGIC; 546 ring->magic = AIO_RING_MAGIC; 572 ring->compat_features = AIO_RING_COMPA 547 ring->compat_features = AIO_RING_COMPAT_FEATURES; 573 ring->incompat_features = AIO_RING_INC 548 ring->incompat_features = AIO_RING_INCOMPAT_FEATURES; 574 ring->header_length = sizeof(struct ai 549 ring->header_length = sizeof(struct aio_ring); 575 flush_dcache_folio(ctx->ring_folios[0] !! 550 kunmap_atomic(ring); >> 551 flush_dcache_page(ctx->ring_pages[0]); 576 552 577 return 0; 553 return 0; 578 } 554 } 579 555 580 #define AIO_EVENTS_PER_PAGE (PAGE_SIZE / s 556 #define AIO_EVENTS_PER_PAGE (PAGE_SIZE / sizeof(struct io_event)) 581 #define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - 557 #define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event)) 582 #define AIO_EVENTS_OFFSET (AIO_EVENTS_PE 558 #define AIO_EVENTS_OFFSET (AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE) 583 559 584 void kiocb_set_cancel_fn(struct kiocb *iocb, k 560 void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) 585 { 561 { 586 struct aio_kiocb *req; !! 562 struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, rw); 587 struct kioctx *ctx; !! 563 struct kioctx *ctx = req->ki_ctx; 588 unsigned long flags; 564 unsigned long flags; 589 565 590 /* << 591 * kiocb didn't come from aio or is ne << 592 * ignore it. << 593 */ << 594 if (!(iocb->ki_flags & IOCB_AIO_RW)) << 595 return; << 596 << 597 req = container_of(iocb, struct aio_ki << 598 << 599 if (WARN_ON_ONCE(!list_empty(&req->ki_ 566 if (WARN_ON_ONCE(!list_empty(&req->ki_list))) 600 return; 567 return; 601 568 602 ctx = req->ki_ctx; << 603 << 604 spin_lock_irqsave(&ctx->ctx_lock, flag 569 spin_lock_irqsave(&ctx->ctx_lock, flags); 605 list_add_tail(&req->ki_list, &ctx->act 570 list_add_tail(&req->ki_list, &ctx->active_reqs); 606 req->ki_cancel = cancel; 571 req->ki_cancel = cancel; 607 spin_unlock_irqrestore(&ctx->ctx_lock, 572 spin_unlock_irqrestore(&ctx->ctx_lock, flags); 608 } 573 } 609 EXPORT_SYMBOL(kiocb_set_cancel_fn); 574 EXPORT_SYMBOL(kiocb_set_cancel_fn); 610 575 611 /* 576 /* 612 * free_ioctx() should be RCU delayed to synch 577 * free_ioctx() should be RCU delayed to synchronize against the RCU 613 * protected lookup_ioctx() and also needs pro 578 * protected lookup_ioctx() and also needs process context to call 614 * aio_free_ring(). Use rcu_work. 579 * aio_free_ring(). Use rcu_work. 615 */ 580 */ 616 static void free_ioctx(struct work_struct *wor 581 static void free_ioctx(struct work_struct *work) 617 { 582 { 618 struct kioctx *ctx = container_of(to_r 583 struct kioctx *ctx = container_of(to_rcu_work(work), struct kioctx, 619 free 584 free_rwork); 620 pr_debug("freeing %p\n", ctx); 585 pr_debug("freeing %p\n", ctx); 621 586 622 aio_free_ring(ctx); 587 aio_free_ring(ctx); 623 free_percpu(ctx->cpu); 588 free_percpu(ctx->cpu); 624 percpu_ref_exit(&ctx->reqs); 589 percpu_ref_exit(&ctx->reqs); 625 percpu_ref_exit(&ctx->users); 590 percpu_ref_exit(&ctx->users); 626 kmem_cache_free(kioctx_cachep, ctx); 591 kmem_cache_free(kioctx_cachep, ctx); 627 } 592 } 628 593 629 static void free_ioctx_reqs(struct percpu_ref 594 static void free_ioctx_reqs(struct percpu_ref *ref) 630 { 595 { 631 struct kioctx *ctx = container_of(ref, 596 struct kioctx *ctx = container_of(ref, struct kioctx, reqs); 632 597 633 /* At this point we know that there ar 598 /* At this point we know that there are no any in-flight requests */ 634 if (ctx->rq_wait && atomic_dec_and_tes 599 if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count)) 635 complete(&ctx->rq_wait->comp); 600 complete(&ctx->rq_wait->comp); 636 601 637 /* Synchronize against RCU protected t 602 /* Synchronize against RCU protected table->table[] dereferences */ 638 INIT_RCU_WORK(&ctx->free_rwork, free_i 603 INIT_RCU_WORK(&ctx->free_rwork, free_ioctx); 639 queue_rcu_work(system_wq, &ctx->free_r 604 queue_rcu_work(system_wq, &ctx->free_rwork); 640 } 605 } 641 606 642 /* 607 /* 643 * When this function runs, the kioctx has bee 608 * When this function runs, the kioctx has been removed from the "hash table" 644 * and ctx->users has dropped to 0, so we know 609 * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted - 645 * now it's safe to cancel any that need to be 610 * now it's safe to cancel any that need to be. 646 */ 611 */ 647 static void free_ioctx_users(struct percpu_ref 612 static void free_ioctx_users(struct percpu_ref *ref) 648 { 613 { 649 struct kioctx *ctx = container_of(ref, 614 struct kioctx *ctx = container_of(ref, struct kioctx, users); 650 struct aio_kiocb *req; 615 struct aio_kiocb *req; 651 616 652 spin_lock_irq(&ctx->ctx_lock); 617 spin_lock_irq(&ctx->ctx_lock); 653 618 654 while (!list_empty(&ctx->active_reqs)) 619 while (!list_empty(&ctx->active_reqs)) { 655 req = list_first_entry(&ctx->a 620 req = list_first_entry(&ctx->active_reqs, 656 struct 621 struct aio_kiocb, ki_list); 657 req->ki_cancel(&req->rw); 622 req->ki_cancel(&req->rw); 658 list_del_init(&req->ki_list); 623 list_del_init(&req->ki_list); 659 } 624 } 660 625 661 spin_unlock_irq(&ctx->ctx_lock); 626 spin_unlock_irq(&ctx->ctx_lock); 662 627 663 percpu_ref_kill(&ctx->reqs); 628 percpu_ref_kill(&ctx->reqs); 664 percpu_ref_put(&ctx->reqs); 629 percpu_ref_put(&ctx->reqs); 665 } 630 } 666 631 667 static int ioctx_add_table(struct kioctx *ctx, 632 static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm) 668 { 633 { 669 unsigned i, new_nr; 634 unsigned i, new_nr; 670 struct kioctx_table *table, *old; 635 struct kioctx_table *table, *old; 671 struct aio_ring *ring; 636 struct aio_ring *ring; 672 637 673 spin_lock(&mm->ioctx_lock); 638 spin_lock(&mm->ioctx_lock); 674 table = rcu_dereference_raw(mm->ioctx_ 639 table = rcu_dereference_raw(mm->ioctx_table); 675 640 676 while (1) { 641 while (1) { 677 if (table) 642 if (table) 678 for (i = 0; i < table- 643 for (i = 0; i < table->nr; i++) 679 if (!rcu_acces 644 if (!rcu_access_pointer(table->table[i])) { 680 ctx->i 645 ctx->id = i; 681 rcu_as 646 rcu_assign_pointer(table->table[i], ctx); 682 spin_u 647 spin_unlock(&mm->ioctx_lock); 683 648 684 /* Whi 649 /* While kioctx setup is in progress, 685 * we 650 * we are protected from page migration 686 * cha !! 651 * changes ring_pages by ->ring_lock. 687 */ 652 */ 688 ring = !! 653 ring = kmap_atomic(ctx->ring_pages[0]); 689 ring-> 654 ring->id = ctx->id; >> 655 kunmap_atomic(ring); 690 return 656 return 0; 691 } 657 } 692 658 693 new_nr = (table ? table->nr : 659 new_nr = (table ? table->nr : 1) * 4; 694 spin_unlock(&mm->ioctx_lock); 660 spin_unlock(&mm->ioctx_lock); 695 661 696 table = kzalloc(struct_size(ta !! 662 table = kzalloc(sizeof(*table) + sizeof(struct kioctx *) * >> 663 new_nr, GFP_KERNEL); 697 if (!table) 664 if (!table) 698 return -ENOMEM; 665 return -ENOMEM; 699 666 700 table->nr = new_nr; 667 table->nr = new_nr; 701 668 702 spin_lock(&mm->ioctx_lock); 669 spin_lock(&mm->ioctx_lock); 703 old = rcu_dereference_raw(mm-> 670 old = rcu_dereference_raw(mm->ioctx_table); 704 671 705 if (!old) { 672 if (!old) { 706 rcu_assign_pointer(mm- 673 rcu_assign_pointer(mm->ioctx_table, table); 707 } else if (table->nr > old->nr 674 } else if (table->nr > old->nr) { 708 memcpy(table->table, o 675 memcpy(table->table, old->table, 709 old->nr * sizeo 676 old->nr * sizeof(struct kioctx *)); 710 677 711 rcu_assign_pointer(mm- 678 rcu_assign_pointer(mm->ioctx_table, table); 712 kfree_rcu(old, rcu); 679 kfree_rcu(old, rcu); 713 } else { 680 } else { 714 kfree(table); 681 kfree(table); 715 table = old; 682 table = old; 716 } 683 } 717 } 684 } 718 } 685 } 719 686 720 static void aio_nr_sub(unsigned nr) 687 static void aio_nr_sub(unsigned nr) 721 { 688 { 722 spin_lock(&aio_nr_lock); 689 spin_lock(&aio_nr_lock); 723 if (WARN_ON(aio_nr - nr > aio_nr)) 690 if (WARN_ON(aio_nr - nr > aio_nr)) 724 aio_nr = 0; 691 aio_nr = 0; 725 else 692 else 726 aio_nr -= nr; 693 aio_nr -= nr; 727 spin_unlock(&aio_nr_lock); 694 spin_unlock(&aio_nr_lock); 728 } 695 } 729 696 730 /* ioctx_alloc 697 /* ioctx_alloc 731 * Allocates and initializes an ioctx. R 698 * Allocates and initializes an ioctx. Returns an ERR_PTR if it failed. 732 */ 699 */ 733 static struct kioctx *ioctx_alloc(unsigned nr_ 700 static struct kioctx *ioctx_alloc(unsigned nr_events) 734 { 701 { 735 struct mm_struct *mm = current->mm; 702 struct mm_struct *mm = current->mm; 736 struct kioctx *ctx; 703 struct kioctx *ctx; 737 int err = -ENOMEM; 704 int err = -ENOMEM; 738 705 739 /* 706 /* 740 * Store the original nr_events -- wha 707 * Store the original nr_events -- what userspace passed to io_setup(), 741 * for counting against the global lim 708 * for counting against the global limit -- before it changes. 742 */ 709 */ 743 unsigned int max_reqs = nr_events; 710 unsigned int max_reqs = nr_events; 744 711 745 /* 712 /* 746 * We keep track of the number of avai 713 * We keep track of the number of available ringbuffer slots, to prevent 747 * overflow (reqs_available), and we a 714 * overflow (reqs_available), and we also use percpu counters for this. 748 * 715 * 749 * So since up to half the slots might 716 * So since up to half the slots might be on other cpu's percpu counters 750 * and unavailable, double nr_events s 717 * and unavailable, double nr_events so userspace sees what they 751 * expected: additionally, we move req 718 * expected: additionally, we move req_batch slots to/from percpu 752 * counters at a time, so make sure th 719 * counters at a time, so make sure that isn't 0: 753 */ 720 */ 754 nr_events = max(nr_events, num_possibl 721 nr_events = max(nr_events, num_possible_cpus() * 4); 755 nr_events *= 2; 722 nr_events *= 2; 756 723 757 /* Prevent overflows */ 724 /* Prevent overflows */ 758 if (nr_events > (0x10000000U / sizeof( 725 if (nr_events > (0x10000000U / sizeof(struct io_event))) { 759 pr_debug("ENOMEM: nr_events to 726 pr_debug("ENOMEM: nr_events too high\n"); 760 return ERR_PTR(-EINVAL); 727 return ERR_PTR(-EINVAL); 761 } 728 } 762 729 763 if (!nr_events || (unsigned long)max_r 730 if (!nr_events || (unsigned long)max_reqs > aio_max_nr) 764 return ERR_PTR(-EAGAIN); 731 return ERR_PTR(-EAGAIN); 765 732 766 ctx = kmem_cache_zalloc(kioctx_cachep, 733 ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL); 767 if (!ctx) 734 if (!ctx) 768 return ERR_PTR(-ENOMEM); 735 return ERR_PTR(-ENOMEM); 769 736 770 ctx->max_reqs = max_reqs; 737 ctx->max_reqs = max_reqs; 771 738 772 spin_lock_init(&ctx->ctx_lock); 739 spin_lock_init(&ctx->ctx_lock); 773 spin_lock_init(&ctx->completion_lock); 740 spin_lock_init(&ctx->completion_lock); 774 mutex_init(&ctx->ring_lock); 741 mutex_init(&ctx->ring_lock); 775 /* Protect against page migration thro 742 /* Protect against page migration throughout kiotx setup by keeping 776 * the ring_lock mutex held until setu 743 * the ring_lock mutex held until setup is complete. */ 777 mutex_lock(&ctx->ring_lock); 744 mutex_lock(&ctx->ring_lock); 778 init_waitqueue_head(&ctx->wait); 745 init_waitqueue_head(&ctx->wait); 779 746 780 INIT_LIST_HEAD(&ctx->active_reqs); 747 INIT_LIST_HEAD(&ctx->active_reqs); 781 748 782 if (percpu_ref_init(&ctx->users, free_ 749 if (percpu_ref_init(&ctx->users, free_ioctx_users, 0, GFP_KERNEL)) 783 goto err; 750 goto err; 784 751 785 if (percpu_ref_init(&ctx->reqs, free_i 752 if (percpu_ref_init(&ctx->reqs, free_ioctx_reqs, 0, GFP_KERNEL)) 786 goto err; 753 goto err; 787 754 788 ctx->cpu = alloc_percpu(struct kioctx_ 755 ctx->cpu = alloc_percpu(struct kioctx_cpu); 789 if (!ctx->cpu) 756 if (!ctx->cpu) 790 goto err; 757 goto err; 791 758 792 err = aio_setup_ring(ctx, nr_events); 759 err = aio_setup_ring(ctx, nr_events); 793 if (err < 0) 760 if (err < 0) 794 goto err; 761 goto err; 795 762 796 atomic_set(&ctx->reqs_available, ctx-> 763 atomic_set(&ctx->reqs_available, ctx->nr_events - 1); 797 ctx->req_batch = (ctx->nr_events - 1) 764 ctx->req_batch = (ctx->nr_events - 1) / (num_possible_cpus() * 4); 798 if (ctx->req_batch < 1) 765 if (ctx->req_batch < 1) 799 ctx->req_batch = 1; 766 ctx->req_batch = 1; 800 767 801 /* limit the number of system wide aio 768 /* limit the number of system wide aios */ 802 spin_lock(&aio_nr_lock); 769 spin_lock(&aio_nr_lock); 803 if (aio_nr + ctx->max_reqs > aio_max_n 770 if (aio_nr + ctx->max_reqs > aio_max_nr || 804 aio_nr + ctx->max_reqs < aio_nr) { 771 aio_nr + ctx->max_reqs < aio_nr) { 805 spin_unlock(&aio_nr_lock); 772 spin_unlock(&aio_nr_lock); 806 err = -EAGAIN; 773 err = -EAGAIN; 807 goto err_ctx; 774 goto err_ctx; 808 } 775 } 809 aio_nr += ctx->max_reqs; 776 aio_nr += ctx->max_reqs; 810 spin_unlock(&aio_nr_lock); 777 spin_unlock(&aio_nr_lock); 811 778 812 percpu_ref_get(&ctx->users); /* io_ 779 percpu_ref_get(&ctx->users); /* io_setup() will drop this ref */ 813 percpu_ref_get(&ctx->reqs); /* fre 780 percpu_ref_get(&ctx->reqs); /* free_ioctx_users() will drop this */ 814 781 815 err = ioctx_add_table(ctx, mm); 782 err = ioctx_add_table(ctx, mm); 816 if (err) 783 if (err) 817 goto err_cleanup; 784 goto err_cleanup; 818 785 819 /* Release the ring_lock mutex now tha 786 /* Release the ring_lock mutex now that all setup is complete. */ 820 mutex_unlock(&ctx->ring_lock); 787 mutex_unlock(&ctx->ring_lock); 821 788 822 pr_debug("allocated ioctx %p[%ld]: mm= 789 pr_debug("allocated ioctx %p[%ld]: mm=%p mask=0x%x\n", 823 ctx, ctx->user_id, mm, ctx->n 790 ctx, ctx->user_id, mm, ctx->nr_events); 824 return ctx; 791 return ctx; 825 792 826 err_cleanup: 793 err_cleanup: 827 aio_nr_sub(ctx->max_reqs); 794 aio_nr_sub(ctx->max_reqs); 828 err_ctx: 795 err_ctx: 829 atomic_set(&ctx->dead, 1); 796 atomic_set(&ctx->dead, 1); 830 if (ctx->mmap_size) 797 if (ctx->mmap_size) 831 vm_munmap(ctx->mmap_base, ctx- 798 vm_munmap(ctx->mmap_base, ctx->mmap_size); 832 aio_free_ring(ctx); 799 aio_free_ring(ctx); 833 err: 800 err: 834 mutex_unlock(&ctx->ring_lock); 801 mutex_unlock(&ctx->ring_lock); 835 free_percpu(ctx->cpu); 802 free_percpu(ctx->cpu); 836 percpu_ref_exit(&ctx->reqs); 803 percpu_ref_exit(&ctx->reqs); 837 percpu_ref_exit(&ctx->users); 804 percpu_ref_exit(&ctx->users); 838 kmem_cache_free(kioctx_cachep, ctx); 805 kmem_cache_free(kioctx_cachep, ctx); 839 pr_debug("error allocating ioctx %d\n" 806 pr_debug("error allocating ioctx %d\n", err); 840 return ERR_PTR(err); 807 return ERR_PTR(err); 841 } 808 } 842 809 843 /* kill_ioctx 810 /* kill_ioctx 844 * Cancels all outstanding aio requests o 811 * Cancels all outstanding aio requests on an aio context. Used 845 * when the processes owning a context ha 812 * when the processes owning a context have all exited to encourage 846 * the rapid destruction of the kioctx. 813 * the rapid destruction of the kioctx. 847 */ 814 */ 848 static int kill_ioctx(struct mm_struct *mm, st 815 static int kill_ioctx(struct mm_struct *mm, struct kioctx *ctx, 849 struct ctx_rq_wait *wait 816 struct ctx_rq_wait *wait) 850 { 817 { 851 struct kioctx_table *table; 818 struct kioctx_table *table; 852 819 853 spin_lock(&mm->ioctx_lock); 820 spin_lock(&mm->ioctx_lock); 854 if (atomic_xchg(&ctx->dead, 1)) { 821 if (atomic_xchg(&ctx->dead, 1)) { 855 spin_unlock(&mm->ioctx_lock); 822 spin_unlock(&mm->ioctx_lock); 856 return -EINVAL; 823 return -EINVAL; 857 } 824 } 858 825 859 table = rcu_dereference_raw(mm->ioctx_ 826 table = rcu_dereference_raw(mm->ioctx_table); 860 WARN_ON(ctx != rcu_access_pointer(tabl 827 WARN_ON(ctx != rcu_access_pointer(table->table[ctx->id])); 861 RCU_INIT_POINTER(table->table[ctx->id] 828 RCU_INIT_POINTER(table->table[ctx->id], NULL); 862 spin_unlock(&mm->ioctx_lock); 829 spin_unlock(&mm->ioctx_lock); 863 830 864 /* free_ioctx_reqs() will do the neces 831 /* free_ioctx_reqs() will do the necessary RCU synchronization */ 865 wake_up_all(&ctx->wait); 832 wake_up_all(&ctx->wait); 866 833 867 /* 834 /* 868 * It'd be more correct to do this in 835 * It'd be more correct to do this in free_ioctx(), after all 869 * the outstanding kiocbs have finishe 836 * the outstanding kiocbs have finished - but by then io_destroy 870 * has already returned, so io_setup() 837 * has already returned, so io_setup() could potentially return 871 * -EAGAIN with no ioctxs actually in 838 * -EAGAIN with no ioctxs actually in use (as far as userspace 872 * could tell). 839 * could tell). 873 */ 840 */ 874 aio_nr_sub(ctx->max_reqs); 841 aio_nr_sub(ctx->max_reqs); 875 842 876 if (ctx->mmap_size) 843 if (ctx->mmap_size) 877 vm_munmap(ctx->mmap_base, ctx- 844 vm_munmap(ctx->mmap_base, ctx->mmap_size); 878 845 879 ctx->rq_wait = wait; 846 ctx->rq_wait = wait; 880 percpu_ref_kill(&ctx->users); 847 percpu_ref_kill(&ctx->users); 881 return 0; 848 return 0; 882 } 849 } 883 850 884 /* 851 /* 885 * exit_aio: called when the last user of mm g 852 * exit_aio: called when the last user of mm goes away. At this point, there is 886 * no way for any new requests to be submited 853 * no way for any new requests to be submited or any of the io_* syscalls to be 887 * called on the context. 854 * called on the context. 888 * 855 * 889 * There may be outstanding kiocbs, but free_i 856 * There may be outstanding kiocbs, but free_ioctx() will explicitly wait on 890 * them. 857 * them. 891 */ 858 */ 892 void exit_aio(struct mm_struct *mm) 859 void exit_aio(struct mm_struct *mm) 893 { 860 { 894 struct kioctx_table *table = rcu_deref 861 struct kioctx_table *table = rcu_dereference_raw(mm->ioctx_table); 895 struct ctx_rq_wait wait; 862 struct ctx_rq_wait wait; 896 int i, skipped; 863 int i, skipped; 897 864 898 if (!table) 865 if (!table) 899 return; 866 return; 900 867 901 atomic_set(&wait.count, table->nr); 868 atomic_set(&wait.count, table->nr); 902 init_completion(&wait.comp); 869 init_completion(&wait.comp); 903 870 904 skipped = 0; 871 skipped = 0; 905 for (i = 0; i < table->nr; ++i) { 872 for (i = 0; i < table->nr; ++i) { 906 struct kioctx *ctx = 873 struct kioctx *ctx = 907 rcu_dereference_protec 874 rcu_dereference_protected(table->table[i], true); 908 875 909 if (!ctx) { 876 if (!ctx) { 910 skipped++; 877 skipped++; 911 continue; 878 continue; 912 } 879 } 913 880 914 /* 881 /* 915 * We don't need to bother wit 882 * We don't need to bother with munmap() here - exit_mmap(mm) 916 * is coming and it'll unmap e 883 * is coming and it'll unmap everything. And we simply can't, 917 * this is not necessarily our 884 * this is not necessarily our ->mm. 918 * Since kill_ioctx() uses non 885 * Since kill_ioctx() uses non-zero ->mmap_size as indicator 919 * that it needs to unmap the 886 * that it needs to unmap the area, just set it to 0. 920 */ 887 */ 921 ctx->mmap_size = 0; 888 ctx->mmap_size = 0; 922 kill_ioctx(mm, ctx, &wait); 889 kill_ioctx(mm, ctx, &wait); 923 } 890 } 924 891 925 if (!atomic_sub_and_test(skipped, &wai 892 if (!atomic_sub_and_test(skipped, &wait.count)) { 926 /* Wait until all IO for the c 893 /* Wait until all IO for the context are done. */ 927 wait_for_completion(&wait.comp 894 wait_for_completion(&wait.comp); 928 } 895 } 929 896 930 RCU_INIT_POINTER(mm->ioctx_table, NULL 897 RCU_INIT_POINTER(mm->ioctx_table, NULL); 931 kfree(table); 898 kfree(table); 932 } 899 } 933 900 934 static void put_reqs_available(struct kioctx * 901 static void put_reqs_available(struct kioctx *ctx, unsigned nr) 935 { 902 { 936 struct kioctx_cpu *kcpu; 903 struct kioctx_cpu *kcpu; 937 unsigned long flags; 904 unsigned long flags; 938 905 939 local_irq_save(flags); 906 local_irq_save(flags); 940 kcpu = this_cpu_ptr(ctx->cpu); 907 kcpu = this_cpu_ptr(ctx->cpu); 941 kcpu->reqs_available += nr; 908 kcpu->reqs_available += nr; 942 909 943 while (kcpu->reqs_available >= ctx->re 910 while (kcpu->reqs_available >= ctx->req_batch * 2) { 944 kcpu->reqs_available -= ctx->r 911 kcpu->reqs_available -= ctx->req_batch; 945 atomic_add(ctx->req_batch, &ct 912 atomic_add(ctx->req_batch, &ctx->reqs_available); 946 } 913 } 947 914 948 local_irq_restore(flags); 915 local_irq_restore(flags); 949 } 916 } 950 917 951 static bool __get_reqs_available(struct kioctx 918 static bool __get_reqs_available(struct kioctx *ctx) 952 { 919 { 953 struct kioctx_cpu *kcpu; 920 struct kioctx_cpu *kcpu; 954 bool ret = false; 921 bool ret = false; 955 unsigned long flags; 922 unsigned long flags; 956 923 957 local_irq_save(flags); 924 local_irq_save(flags); 958 kcpu = this_cpu_ptr(ctx->cpu); 925 kcpu = this_cpu_ptr(ctx->cpu); 959 if (!kcpu->reqs_available) { 926 if (!kcpu->reqs_available) { 960 int avail = atomic_read(&ctx-> !! 927 int old, avail = atomic_read(&ctx->reqs_available); 961 928 962 do { 929 do { 963 if (avail < ctx->req_b 930 if (avail < ctx->req_batch) 964 goto out; 931 goto out; 965 } while (!atomic_try_cmpxchg(& !! 932 966 & !! 933 old = avail; >> 934 avail = atomic_cmpxchg(&ctx->reqs_available, >> 935 avail, avail - ctx->req_batch); >> 936 } while (avail != old); 967 937 968 kcpu->reqs_available += ctx->r 938 kcpu->reqs_available += ctx->req_batch; 969 } 939 } 970 940 971 ret = true; 941 ret = true; 972 kcpu->reqs_available--; 942 kcpu->reqs_available--; 973 out: 943 out: 974 local_irq_restore(flags); 944 local_irq_restore(flags); 975 return ret; 945 return ret; 976 } 946 } 977 947 978 /* refill_reqs_available 948 /* refill_reqs_available 979 * Updates the reqs_available reference c 949 * Updates the reqs_available reference counts used for tracking the 980 * number of free slots in the completion 950 * number of free slots in the completion ring. This can be called 981 * from aio_complete() (to optimistically 951 * from aio_complete() (to optimistically update reqs_available) or 982 * from aio_get_req() (the we're out of e 952 * from aio_get_req() (the we're out of events case). It must be 983 * called holding ctx->completion_lock. 953 * called holding ctx->completion_lock. 984 */ 954 */ 985 static void refill_reqs_available(struct kioct 955 static void refill_reqs_available(struct kioctx *ctx, unsigned head, 986 unsigned tai 956 unsigned tail) 987 { 957 { 988 unsigned events_in_ring, completed; 958 unsigned events_in_ring, completed; 989 959 990 /* Clamp head since userland can write 960 /* Clamp head since userland can write to it. */ 991 head %= ctx->nr_events; 961 head %= ctx->nr_events; 992 if (head <= tail) 962 if (head <= tail) 993 events_in_ring = tail - head; 963 events_in_ring = tail - head; 994 else 964 else 995 events_in_ring = ctx->nr_event 965 events_in_ring = ctx->nr_events - (head - tail); 996 966 997 completed = ctx->completed_events; 967 completed = ctx->completed_events; 998 if (events_in_ring < completed) 968 if (events_in_ring < completed) 999 completed -= events_in_ring; 969 completed -= events_in_ring; 1000 else 970 else 1001 completed = 0; 971 completed = 0; 1002 972 1003 if (!completed) 973 if (!completed) 1004 return; 974 return; 1005 975 1006 ctx->completed_events -= completed; 976 ctx->completed_events -= completed; 1007 put_reqs_available(ctx, completed); 977 put_reqs_available(ctx, completed); 1008 } 978 } 1009 979 1010 /* user_refill_reqs_available 980 /* user_refill_reqs_available 1011 * Called to refill reqs_available when 981 * Called to refill reqs_available when aio_get_req() encounters an 1012 * out of space in the completion ring. 982 * out of space in the completion ring. 1013 */ 983 */ 1014 static void user_refill_reqs_available(struct 984 static void user_refill_reqs_available(struct kioctx *ctx) 1015 { 985 { 1016 spin_lock_irq(&ctx->completion_lock); 986 spin_lock_irq(&ctx->completion_lock); 1017 if (ctx->completed_events) { 987 if (ctx->completed_events) { 1018 struct aio_ring *ring; 988 struct aio_ring *ring; 1019 unsigned head; 989 unsigned head; 1020 990 1021 /* Access of ring->head may r 991 /* Access of ring->head may race with aio_read_events_ring() 1022 * here, but that's okay sinc 992 * here, but that's okay since whether we read the old version 1023 * or the new version, and ei 993 * or the new version, and either will be valid. The important 1024 * part is that head cannot p 994 * part is that head cannot pass tail since we prevent 1025 * aio_complete() from updati 995 * aio_complete() from updating tail by holding 1026 * ctx->completion_lock. Eve 996 * ctx->completion_lock. Even if head is invalid, the check 1027 * against ctx->completed_eve 997 * against ctx->completed_events below will make sure we do the 1028 * safe/right thing. 998 * safe/right thing. 1029 */ 999 */ 1030 ring = folio_address(ctx->rin !! 1000 ring = kmap_atomic(ctx->ring_pages[0]); 1031 head = ring->head; 1001 head = ring->head; >> 1002 kunmap_atomic(ring); 1032 1003 1033 refill_reqs_available(ctx, he 1004 refill_reqs_available(ctx, head, ctx->tail); 1034 } 1005 } 1035 1006 1036 spin_unlock_irq(&ctx->completion_lock 1007 spin_unlock_irq(&ctx->completion_lock); 1037 } 1008 } 1038 1009 1039 static bool get_reqs_available(struct kioctx 1010 static bool get_reqs_available(struct kioctx *ctx) 1040 { 1011 { 1041 if (__get_reqs_available(ctx)) 1012 if (__get_reqs_available(ctx)) 1042 return true; 1013 return true; 1043 user_refill_reqs_available(ctx); 1014 user_refill_reqs_available(ctx); 1044 return __get_reqs_available(ctx); 1015 return __get_reqs_available(ctx); 1045 } 1016 } 1046 1017 1047 /* aio_get_req 1018 /* aio_get_req 1048 * Allocate a slot for an aio request. 1019 * Allocate a slot for an aio request. 1049 * Returns NULL if no requests are free. 1020 * Returns NULL if no requests are free. 1050 * 1021 * 1051 * The refcount is initialized to 2 - one for 1022 * The refcount is initialized to 2 - one for the async op completion, 1052 * one for the synchronous code that does thi 1023 * one for the synchronous code that does this. 1053 */ 1024 */ 1054 static inline struct aio_kiocb *aio_get_req(s 1025 static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx) 1055 { 1026 { 1056 struct aio_kiocb *req; 1027 struct aio_kiocb *req; 1057 1028 1058 req = kmem_cache_alloc(kiocb_cachep, 1029 req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL); 1059 if (unlikely(!req)) 1030 if (unlikely(!req)) 1060 return NULL; 1031 return NULL; 1061 1032 1062 if (unlikely(!get_reqs_available(ctx) 1033 if (unlikely(!get_reqs_available(ctx))) { 1063 kmem_cache_free(kiocb_cachep, 1034 kmem_cache_free(kiocb_cachep, req); 1064 return NULL; 1035 return NULL; 1065 } 1036 } 1066 1037 1067 percpu_ref_get(&ctx->reqs); 1038 percpu_ref_get(&ctx->reqs); 1068 req->ki_ctx = ctx; 1039 req->ki_ctx = ctx; 1069 INIT_LIST_HEAD(&req->ki_list); 1040 INIT_LIST_HEAD(&req->ki_list); 1070 refcount_set(&req->ki_refcnt, 2); 1041 refcount_set(&req->ki_refcnt, 2); 1071 req->ki_eventfd = NULL; 1042 req->ki_eventfd = NULL; 1072 return req; 1043 return req; 1073 } 1044 } 1074 1045 1075 static struct kioctx *lookup_ioctx(unsigned l 1046 static struct kioctx *lookup_ioctx(unsigned long ctx_id) 1076 { 1047 { 1077 struct aio_ring __user *ring = (void 1048 struct aio_ring __user *ring = (void __user *)ctx_id; 1078 struct mm_struct *mm = current->mm; 1049 struct mm_struct *mm = current->mm; 1079 struct kioctx *ctx, *ret = NULL; 1050 struct kioctx *ctx, *ret = NULL; 1080 struct kioctx_table *table; 1051 struct kioctx_table *table; 1081 unsigned id; 1052 unsigned id; 1082 1053 1083 if (get_user(id, &ring->id)) 1054 if (get_user(id, &ring->id)) 1084 return NULL; 1055 return NULL; 1085 1056 1086 rcu_read_lock(); 1057 rcu_read_lock(); 1087 table = rcu_dereference(mm->ioctx_tab 1058 table = rcu_dereference(mm->ioctx_table); 1088 1059 1089 if (!table || id >= table->nr) 1060 if (!table || id >= table->nr) 1090 goto out; 1061 goto out; 1091 1062 1092 id = array_index_nospec(id, table->nr 1063 id = array_index_nospec(id, table->nr); 1093 ctx = rcu_dereference(table->table[id 1064 ctx = rcu_dereference(table->table[id]); 1094 if (ctx && ctx->user_id == ctx_id) { 1065 if (ctx && ctx->user_id == ctx_id) { 1095 if (percpu_ref_tryget_live(&c 1066 if (percpu_ref_tryget_live(&ctx->users)) 1096 ret = ctx; 1067 ret = ctx; 1097 } 1068 } 1098 out: 1069 out: 1099 rcu_read_unlock(); 1070 rcu_read_unlock(); 1100 return ret; 1071 return ret; 1101 } 1072 } 1102 1073 1103 static inline void iocb_destroy(struct aio_ki 1074 static inline void iocb_destroy(struct aio_kiocb *iocb) 1104 { 1075 { 1105 if (iocb->ki_eventfd) 1076 if (iocb->ki_eventfd) 1106 eventfd_ctx_put(iocb->ki_even 1077 eventfd_ctx_put(iocb->ki_eventfd); 1107 if (iocb->ki_filp) 1078 if (iocb->ki_filp) 1108 fput(iocb->ki_filp); 1079 fput(iocb->ki_filp); 1109 percpu_ref_put(&iocb->ki_ctx->reqs); 1080 percpu_ref_put(&iocb->ki_ctx->reqs); 1110 kmem_cache_free(kiocb_cachep, iocb); 1081 kmem_cache_free(kiocb_cachep, iocb); 1111 } 1082 } 1112 1083 1113 struct aio_waiter { << 1114 struct wait_queue_entry w; << 1115 size_t min_nr; << 1116 }; << 1117 << 1118 /* aio_complete 1084 /* aio_complete 1119 * Called when the io request on the giv 1085 * Called when the io request on the given iocb is complete. 1120 */ 1086 */ 1121 static void aio_complete(struct aio_kiocb *io 1087 static void aio_complete(struct aio_kiocb *iocb) 1122 { 1088 { 1123 struct kioctx *ctx = iocb->ki_ctx; 1089 struct kioctx *ctx = iocb->ki_ctx; 1124 struct aio_ring *ring; 1090 struct aio_ring *ring; 1125 struct io_event *ev_page, *event; 1091 struct io_event *ev_page, *event; 1126 unsigned tail, pos, head, avail; !! 1092 unsigned tail, pos, head; 1127 unsigned long flags; 1093 unsigned long flags; 1128 1094 1129 /* 1095 /* 1130 * Add a completion event to the ring 1096 * Add a completion event to the ring buffer. Must be done holding 1131 * ctx->completion_lock to prevent ot 1097 * ctx->completion_lock to prevent other code from messing with the tail 1132 * pointer since we might be called f 1098 * pointer since we might be called from irq context. 1133 */ 1099 */ 1134 spin_lock_irqsave(&ctx->completion_lo 1100 spin_lock_irqsave(&ctx->completion_lock, flags); 1135 1101 1136 tail = ctx->tail; 1102 tail = ctx->tail; 1137 pos = tail + AIO_EVENTS_OFFSET; 1103 pos = tail + AIO_EVENTS_OFFSET; 1138 1104 1139 if (++tail >= ctx->nr_events) 1105 if (++tail >= ctx->nr_events) 1140 tail = 0; 1106 tail = 0; 1141 1107 1142 ev_page = folio_address(ctx->ring_fol !! 1108 ev_page = kmap_atomic(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]); 1143 event = ev_page + pos % AIO_EVENTS_PE 1109 event = ev_page + pos % AIO_EVENTS_PER_PAGE; 1144 1110 1145 *event = iocb->ki_res; 1111 *event = iocb->ki_res; 1146 1112 1147 flush_dcache_folio(ctx->ring_folios[p !! 1113 kunmap_atomic(ev_page); >> 1114 flush_dcache_page(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]); 1148 1115 1149 pr_debug("%p[%u]: %p: %p %Lx %Lx %Lx\ 1116 pr_debug("%p[%u]: %p: %p %Lx %Lx %Lx\n", ctx, tail, iocb, 1150 (void __user *)(unsigned lon 1117 (void __user *)(unsigned long)iocb->ki_res.obj, 1151 iocb->ki_res.data, iocb->ki_ 1118 iocb->ki_res.data, iocb->ki_res.res, iocb->ki_res.res2); 1152 1119 1153 /* after flagging the request as done 1120 /* after flagging the request as done, we 1154 * must never even look at it again 1121 * must never even look at it again 1155 */ 1122 */ 1156 smp_wmb(); /* make event visible 1123 smp_wmb(); /* make event visible before updating tail */ 1157 1124 1158 ctx->tail = tail; 1125 ctx->tail = tail; 1159 1126 1160 ring = folio_address(ctx->ring_folios !! 1127 ring = kmap_atomic(ctx->ring_pages[0]); 1161 head = ring->head; 1128 head = ring->head; 1162 ring->tail = tail; 1129 ring->tail = tail; 1163 flush_dcache_folio(ctx->ring_folios[0 !! 1130 kunmap_atomic(ring); >> 1131 flush_dcache_page(ctx->ring_pages[0]); 1164 1132 1165 ctx->completed_events++; 1133 ctx->completed_events++; 1166 if (ctx->completed_events > 1) 1134 if (ctx->completed_events > 1) 1167 refill_reqs_available(ctx, he 1135 refill_reqs_available(ctx, head, tail); 1168 << 1169 avail = tail > head << 1170 ? tail - head << 1171 : tail + ctx->nr_events - hea << 1172 spin_unlock_irqrestore(&ctx->completi 1136 spin_unlock_irqrestore(&ctx->completion_lock, flags); 1173 1137 1174 pr_debug("added to ring %p at [%u]\n" 1138 pr_debug("added to ring %p at [%u]\n", iocb, tail); 1175 1139 1176 /* 1140 /* 1177 * Check if the user asked us to deli 1141 * Check if the user asked us to deliver the result through an 1178 * eventfd. The eventfd_signal() func 1142 * eventfd. The eventfd_signal() function is safe to be called 1179 * from IRQ context. 1143 * from IRQ context. 1180 */ 1144 */ 1181 if (iocb->ki_eventfd) 1145 if (iocb->ki_eventfd) 1182 eventfd_signal(iocb->ki_event !! 1146 eventfd_signal(iocb->ki_eventfd, 1); 1183 1147 1184 /* 1148 /* 1185 * We have to order our ring_info tai 1149 * We have to order our ring_info tail store above and test 1186 * of the wait list below outside the 1150 * of the wait list below outside the wait lock. This is 1187 * like in wake_up_bit() where cleari 1151 * like in wake_up_bit() where clearing a bit has to be 1188 * ordered with the unlocked test. 1152 * ordered with the unlocked test. 1189 */ 1153 */ 1190 smp_mb(); 1154 smp_mb(); 1191 1155 1192 if (waitqueue_active(&ctx->wait)) { !! 1156 if (waitqueue_active(&ctx->wait)) 1193 struct aio_waiter *curr, *nex !! 1157 wake_up(&ctx->wait); 1194 unsigned long flags; << 1195 << 1196 spin_lock_irqsave(&ctx->wait. << 1197 list_for_each_entry_safe(curr << 1198 if (avail >= curr->mi << 1199 wake_up_proce << 1200 list_del_init << 1201 } << 1202 spin_unlock_irqrestore(&ctx-> << 1203 } << 1204 } 1158 } 1205 1159 1206 static inline void iocb_put(struct aio_kiocb 1160 static inline void iocb_put(struct aio_kiocb *iocb) 1207 { 1161 { 1208 if (refcount_dec_and_test(&iocb->ki_r 1162 if (refcount_dec_and_test(&iocb->ki_refcnt)) { 1209 aio_complete(iocb); 1163 aio_complete(iocb); 1210 iocb_destroy(iocb); 1164 iocb_destroy(iocb); 1211 } 1165 } 1212 } 1166 } 1213 1167 1214 /* aio_read_events_ring 1168 /* aio_read_events_ring 1215 * Pull an event off of the ioctx's even 1169 * Pull an event off of the ioctx's event ring. Returns the number of 1216 * events fetched 1170 * events fetched 1217 */ 1171 */ 1218 static long aio_read_events_ring(struct kioct 1172 static long aio_read_events_ring(struct kioctx *ctx, 1219 struct io_ev 1173 struct io_event __user *event, long nr) 1220 { 1174 { 1221 struct aio_ring *ring; 1175 struct aio_ring *ring; 1222 unsigned head, tail, pos; 1176 unsigned head, tail, pos; 1223 long ret = 0; 1177 long ret = 0; 1224 int copy_ret; 1178 int copy_ret; 1225 1179 1226 /* 1180 /* 1227 * The mutex can block and wake us up 1181 * The mutex can block and wake us up and that will cause 1228 * wait_event_interruptible_hrtimeout 1182 * wait_event_interruptible_hrtimeout() to schedule without sleeping 1229 * and repeat. This should be rare en 1183 * and repeat. This should be rare enough that it doesn't cause 1230 * peformance issues. See the comment 1184 * peformance issues. See the comment in read_events() for more detail. 1231 */ 1185 */ 1232 sched_annotate_sleep(); 1186 sched_annotate_sleep(); 1233 mutex_lock(&ctx->ring_lock); 1187 mutex_lock(&ctx->ring_lock); 1234 1188 1235 /* Access to ->ring_folios here is pr !! 1189 /* Access to ->ring_pages here is protected by ctx->ring_lock. */ 1236 ring = folio_address(ctx->ring_folios !! 1190 ring = kmap_atomic(ctx->ring_pages[0]); 1237 head = ring->head; 1191 head = ring->head; 1238 tail = ring->tail; 1192 tail = ring->tail; >> 1193 kunmap_atomic(ring); 1239 1194 1240 /* 1195 /* 1241 * Ensure that once we've read the cu 1196 * Ensure that once we've read the current tail pointer, that 1242 * we also see the events that were s 1197 * we also see the events that were stored up to the tail. 1243 */ 1198 */ 1244 smp_rmb(); 1199 smp_rmb(); 1245 1200 1246 pr_debug("h%u t%u m%u\n", head, tail, 1201 pr_debug("h%u t%u m%u\n", head, tail, ctx->nr_events); 1247 1202 1248 if (head == tail) 1203 if (head == tail) 1249 goto out; 1204 goto out; 1250 1205 1251 head %= ctx->nr_events; 1206 head %= ctx->nr_events; 1252 tail %= ctx->nr_events; 1207 tail %= ctx->nr_events; 1253 1208 1254 while (ret < nr) { 1209 while (ret < nr) { 1255 long avail; 1210 long avail; 1256 struct io_event *ev; 1211 struct io_event *ev; 1257 struct folio *folio; !! 1212 struct page *page; 1258 1213 1259 avail = (head <= tail ? tail 1214 avail = (head <= tail ? tail : ctx->nr_events) - head; 1260 if (head == tail) 1215 if (head == tail) 1261 break; 1216 break; 1262 1217 1263 pos = head + AIO_EVENTS_OFFSE 1218 pos = head + AIO_EVENTS_OFFSET; 1264 folio = ctx->ring_folios[pos !! 1219 page = ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]; 1265 pos %= AIO_EVENTS_PER_PAGE; 1220 pos %= AIO_EVENTS_PER_PAGE; 1266 1221 1267 avail = min(avail, nr - ret); 1222 avail = min(avail, nr - ret); 1268 avail = min_t(long, avail, AI 1223 avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - pos); 1269 1224 1270 ev = folio_address(folio); !! 1225 ev = kmap(page); 1271 copy_ret = copy_to_user(event 1226 copy_ret = copy_to_user(event + ret, ev + pos, 1272 sizeo 1227 sizeof(*ev) * avail); >> 1228 kunmap(page); 1273 1229 1274 if (unlikely(copy_ret)) { 1230 if (unlikely(copy_ret)) { 1275 ret = -EFAULT; 1231 ret = -EFAULT; 1276 goto out; 1232 goto out; 1277 } 1233 } 1278 1234 1279 ret += avail; 1235 ret += avail; 1280 head += avail; 1236 head += avail; 1281 head %= ctx->nr_events; 1237 head %= ctx->nr_events; 1282 } 1238 } 1283 1239 1284 ring = folio_address(ctx->ring_folios !! 1240 ring = kmap_atomic(ctx->ring_pages[0]); 1285 ring->head = head; 1241 ring->head = head; 1286 flush_dcache_folio(ctx->ring_folios[0 !! 1242 kunmap_atomic(ring); >> 1243 flush_dcache_page(ctx->ring_pages[0]); 1287 1244 1288 pr_debug("%li h%u t%u\n", ret, head, 1245 pr_debug("%li h%u t%u\n", ret, head, tail); 1289 out: 1246 out: 1290 mutex_unlock(&ctx->ring_lock); 1247 mutex_unlock(&ctx->ring_lock); 1291 1248 1292 return ret; 1249 return ret; 1293 } 1250 } 1294 1251 1295 static bool aio_read_events(struct kioctx *ct 1252 static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr, 1296 struct io_event _ 1253 struct io_event __user *event, long *i) 1297 { 1254 { 1298 long ret = aio_read_events_ring(ctx, 1255 long ret = aio_read_events_ring(ctx, event + *i, nr - *i); 1299 1256 1300 if (ret > 0) 1257 if (ret > 0) 1301 *i += ret; 1258 *i += ret; 1302 1259 1303 if (unlikely(atomic_read(&ctx->dead)) 1260 if (unlikely(atomic_read(&ctx->dead))) 1304 ret = -EINVAL; 1261 ret = -EINVAL; 1305 1262 1306 if (!*i) 1263 if (!*i) 1307 *i = ret; 1264 *i = ret; 1308 1265 1309 return ret < 0 || *i >= min_nr; 1266 return ret < 0 || *i >= min_nr; 1310 } 1267 } 1311 1268 1312 static long read_events(struct kioctx *ctx, l 1269 static long read_events(struct kioctx *ctx, long min_nr, long nr, 1313 struct io_event __use 1270 struct io_event __user *event, 1314 ktime_t until) 1271 ktime_t until) 1315 { 1272 { 1316 struct hrtimer_sleeper t; !! 1273 long ret = 0; 1317 struct aio_waiter w; << 1318 long ret = 0, ret2 = 0; << 1319 1274 1320 /* 1275 /* 1321 * Note that aio_read_events() is bei 1276 * Note that aio_read_events() is being called as the conditional - i.e. 1322 * we're calling it after prepare_to_ 1277 * we're calling it after prepare_to_wait() has set task state to 1323 * TASK_INTERRUPTIBLE. 1278 * TASK_INTERRUPTIBLE. 1324 * 1279 * 1325 * But aio_read_events() can block, a 1280 * But aio_read_events() can block, and if it blocks it's going to flip 1326 * the task state back to TASK_RUNNIN 1281 * the task state back to TASK_RUNNING. 1327 * 1282 * 1328 * This should be ok, provided it doe 1283 * This should be ok, provided it doesn't flip the state back to 1329 * TASK_RUNNING and return 0 too much 1284 * TASK_RUNNING and return 0 too much - that causes us to spin. That 1330 * will only happen if the mutex_lock 1285 * will only happen if the mutex_lock() call blocks, and we then find 1331 * the ringbuffer empty. So in practi 1286 * the ringbuffer empty. So in practice we should be ok, but it's 1332 * something to be aware of when touc 1287 * something to be aware of when touching this code. 1333 */ 1288 */ 1334 aio_read_events(ctx, min_nr, nr, even !! 1289 if (until == 0) 1335 if (until == 0 || ret < 0 || ret >= m !! 1290 aio_read_events(ctx, min_nr, nr, event, &ret); 1336 return ret; !! 1291 else 1337 !! 1292 wait_event_interruptible_hrtimeout(ctx->wait, 1338 hrtimer_init_sleeper_on_stack(&t, CLO !! 1293 aio_read_events(ctx, min_nr, nr, event, &ret), 1339 if (until != KTIME_MAX) { !! 1294 until); 1340 hrtimer_set_expires_range_ns( << 1341 hrtimer_sleeper_start_expires << 1342 } << 1343 << 1344 init_wait(&w.w); << 1345 << 1346 while (1) { << 1347 unsigned long nr_got = ret; << 1348 << 1349 w.min_nr = min_nr - ret; << 1350 << 1351 ret2 = prepare_to_wait_event( << 1352 if (!ret2 && !t.task) << 1353 ret2 = -ETIME; << 1354 << 1355 if (aio_read_events(ctx, min_ << 1356 break; << 1357 << 1358 if (nr_got == ret) << 1359 schedule(); << 1360 } << 1361 << 1362 finish_wait(&ctx->wait, &w.w); << 1363 hrtimer_cancel(&t.timer); << 1364 destroy_hrtimer_on_stack(&t.timer); << 1365 << 1366 return ret; 1295 return ret; 1367 } 1296 } 1368 1297 1369 /* sys_io_setup: 1298 /* sys_io_setup: 1370 * Create an aio_context capable of rece 1299 * Create an aio_context capable of receiving at least nr_events. 1371 * ctxp must not point to an aio_context 1300 * ctxp must not point to an aio_context that already exists, and 1372 * must be initialized to 0 prior to the 1301 * must be initialized to 0 prior to the call. On successful 1373 * creation of the aio_context, *ctxp is 1302 * creation of the aio_context, *ctxp is filled in with the resulting 1374 * handle. May fail with -EINVAL if *ct 1303 * handle. May fail with -EINVAL if *ctxp is not initialized, 1375 * if the specified nr_events exceeds in 1304 * if the specified nr_events exceeds internal limits. May fail 1376 * with -EAGAIN if the specified nr_even 1305 * with -EAGAIN if the specified nr_events exceeds the user's limit 1377 * of available events. May fail with - 1306 * of available events. May fail with -ENOMEM if insufficient kernel 1378 * resources are available. May fail wi 1307 * resources are available. May fail with -EFAULT if an invalid 1379 * pointer is passed for ctxp. Will fai 1308 * pointer is passed for ctxp. Will fail with -ENOSYS if not 1380 * implemented. 1309 * implemented. 1381 */ 1310 */ 1382 SYSCALL_DEFINE2(io_setup, unsigned, nr_events 1311 SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp) 1383 { 1312 { 1384 struct kioctx *ioctx = NULL; 1313 struct kioctx *ioctx = NULL; 1385 unsigned long ctx; 1314 unsigned long ctx; 1386 long ret; 1315 long ret; 1387 1316 1388 ret = get_user(ctx, ctxp); 1317 ret = get_user(ctx, ctxp); 1389 if (unlikely(ret)) 1318 if (unlikely(ret)) 1390 goto out; 1319 goto out; 1391 1320 1392 ret = -EINVAL; 1321 ret = -EINVAL; 1393 if (unlikely(ctx || nr_events == 0)) 1322 if (unlikely(ctx || nr_events == 0)) { 1394 pr_debug("EINVAL: ctx %lu nr_ 1323 pr_debug("EINVAL: ctx %lu nr_events %u\n", 1395 ctx, nr_events); 1324 ctx, nr_events); 1396 goto out; 1325 goto out; 1397 } 1326 } 1398 1327 1399 ioctx = ioctx_alloc(nr_events); 1328 ioctx = ioctx_alloc(nr_events); 1400 ret = PTR_ERR(ioctx); 1329 ret = PTR_ERR(ioctx); 1401 if (!IS_ERR(ioctx)) { 1330 if (!IS_ERR(ioctx)) { 1402 ret = put_user(ioctx->user_id 1331 ret = put_user(ioctx->user_id, ctxp); 1403 if (ret) 1332 if (ret) 1404 kill_ioctx(current->m 1333 kill_ioctx(current->mm, ioctx, NULL); 1405 percpu_ref_put(&ioctx->users) 1334 percpu_ref_put(&ioctx->users); 1406 } 1335 } 1407 1336 1408 out: 1337 out: 1409 return ret; 1338 return ret; 1410 } 1339 } 1411 1340 1412 #ifdef CONFIG_COMPAT 1341 #ifdef CONFIG_COMPAT 1413 COMPAT_SYSCALL_DEFINE2(io_setup, unsigned, nr 1342 COMPAT_SYSCALL_DEFINE2(io_setup, unsigned, nr_events, u32 __user *, ctx32p) 1414 { 1343 { 1415 struct kioctx *ioctx = NULL; 1344 struct kioctx *ioctx = NULL; 1416 unsigned long ctx; 1345 unsigned long ctx; 1417 long ret; 1346 long ret; 1418 1347 1419 ret = get_user(ctx, ctx32p); 1348 ret = get_user(ctx, ctx32p); 1420 if (unlikely(ret)) 1349 if (unlikely(ret)) 1421 goto out; 1350 goto out; 1422 1351 1423 ret = -EINVAL; 1352 ret = -EINVAL; 1424 if (unlikely(ctx || nr_events == 0)) 1353 if (unlikely(ctx || nr_events == 0)) { 1425 pr_debug("EINVAL: ctx %lu nr_ 1354 pr_debug("EINVAL: ctx %lu nr_events %u\n", 1426 ctx, nr_events); 1355 ctx, nr_events); 1427 goto out; 1356 goto out; 1428 } 1357 } 1429 1358 1430 ioctx = ioctx_alloc(nr_events); 1359 ioctx = ioctx_alloc(nr_events); 1431 ret = PTR_ERR(ioctx); 1360 ret = PTR_ERR(ioctx); 1432 if (!IS_ERR(ioctx)) { 1361 if (!IS_ERR(ioctx)) { 1433 /* truncating is ok because i 1362 /* truncating is ok because it's a user address */ 1434 ret = put_user((u32)ioctx->us 1363 ret = put_user((u32)ioctx->user_id, ctx32p); 1435 if (ret) 1364 if (ret) 1436 kill_ioctx(current->m 1365 kill_ioctx(current->mm, ioctx, NULL); 1437 percpu_ref_put(&ioctx->users) 1366 percpu_ref_put(&ioctx->users); 1438 } 1367 } 1439 1368 1440 out: 1369 out: 1441 return ret; 1370 return ret; 1442 } 1371 } 1443 #endif 1372 #endif 1444 1373 1445 /* sys_io_destroy: 1374 /* sys_io_destroy: 1446 * Destroy the aio_context specified. M 1375 * Destroy the aio_context specified. May cancel any outstanding 1447 * AIOs and block on completion. Will f 1376 * AIOs and block on completion. Will fail with -ENOSYS if not 1448 * implemented. May fail with -EINVAL i 1377 * implemented. May fail with -EINVAL if the context pointed to 1449 * is invalid. 1378 * is invalid. 1450 */ 1379 */ 1451 SYSCALL_DEFINE1(io_destroy, aio_context_t, ct 1380 SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx) 1452 { 1381 { 1453 struct kioctx *ioctx = lookup_ioctx(c 1382 struct kioctx *ioctx = lookup_ioctx(ctx); 1454 if (likely(NULL != ioctx)) { 1383 if (likely(NULL != ioctx)) { 1455 struct ctx_rq_wait wait; 1384 struct ctx_rq_wait wait; 1456 int ret; 1385 int ret; 1457 1386 1458 init_completion(&wait.comp); 1387 init_completion(&wait.comp); 1459 atomic_set(&wait.count, 1); 1388 atomic_set(&wait.count, 1); 1460 1389 1461 /* Pass requests_done to kill 1390 /* Pass requests_done to kill_ioctx() where it can be set 1462 * in a thread-safe way. If w 1391 * in a thread-safe way. If we try to set it here then we have 1463 * a race condition if two io 1392 * a race condition if two io_destroy() called simultaneously. 1464 */ 1393 */ 1465 ret = kill_ioctx(current->mm, 1394 ret = kill_ioctx(current->mm, ioctx, &wait); 1466 percpu_ref_put(&ioctx->users) 1395 percpu_ref_put(&ioctx->users); 1467 1396 1468 /* Wait until all IO for the 1397 /* Wait until all IO for the context are done. Otherwise kernel 1469 * keep using user-space buff 1398 * keep using user-space buffers even if user thinks the context 1470 * is destroyed. 1399 * is destroyed. 1471 */ 1400 */ 1472 if (!ret) 1401 if (!ret) 1473 wait_for_completion(& 1402 wait_for_completion(&wait.comp); 1474 1403 1475 return ret; 1404 return ret; 1476 } 1405 } 1477 pr_debug("EINVAL: invalid context id\ 1406 pr_debug("EINVAL: invalid context id\n"); 1478 return -EINVAL; 1407 return -EINVAL; 1479 } 1408 } 1480 1409 1481 static void aio_remove_iocb(struct aio_kiocb 1410 static void aio_remove_iocb(struct aio_kiocb *iocb) 1482 { 1411 { 1483 struct kioctx *ctx = iocb->ki_ctx; 1412 struct kioctx *ctx = iocb->ki_ctx; 1484 unsigned long flags; 1413 unsigned long flags; 1485 1414 1486 spin_lock_irqsave(&ctx->ctx_lock, fla 1415 spin_lock_irqsave(&ctx->ctx_lock, flags); 1487 list_del(&iocb->ki_list); 1416 list_del(&iocb->ki_list); 1488 spin_unlock_irqrestore(&ctx->ctx_lock 1417 spin_unlock_irqrestore(&ctx->ctx_lock, flags); 1489 } 1418 } 1490 1419 1491 static void aio_complete_rw(struct kiocb *kio !! 1420 static void aio_complete_rw(struct kiocb *kiocb, long res, long res2) 1492 { 1421 { 1493 struct aio_kiocb *iocb = container_of 1422 struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, rw); 1494 1423 1495 if (!list_empty_careful(&iocb->ki_lis 1424 if (!list_empty_careful(&iocb->ki_list)) 1496 aio_remove_iocb(iocb); 1425 aio_remove_iocb(iocb); 1497 1426 1498 if (kiocb->ki_flags & IOCB_WRITE) { 1427 if (kiocb->ki_flags & IOCB_WRITE) { 1499 struct inode *inode = file_in 1428 struct inode *inode = file_inode(kiocb->ki_filp); 1500 1429 >> 1430 /* >> 1431 * Tell lockdep we inherited freeze protection from submission >> 1432 * thread. >> 1433 */ 1501 if (S_ISREG(inode->i_mode)) 1434 if (S_ISREG(inode->i_mode)) 1502 kiocb_end_write(kiocb !! 1435 __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); >> 1436 file_end_write(kiocb->ki_filp); 1503 } 1437 } 1504 1438 1505 iocb->ki_res.res = res; 1439 iocb->ki_res.res = res; 1506 iocb->ki_res.res2 = 0; !! 1440 iocb->ki_res.res2 = res2; 1507 iocb_put(iocb); 1441 iocb_put(iocb); 1508 } 1442 } 1509 1443 1510 static int aio_prep_rw(struct kiocb *req, con !! 1444 static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb) 1511 { 1445 { 1512 int ret; 1446 int ret; 1513 1447 1514 req->ki_complete = aio_complete_rw; 1448 req->ki_complete = aio_complete_rw; 1515 req->private = NULL; 1449 req->private = NULL; 1516 req->ki_pos = iocb->aio_offset; 1450 req->ki_pos = iocb->aio_offset; 1517 req->ki_flags = req->ki_filp->f_iocb_ !! 1451 req->ki_flags = iocb_flags(req->ki_filp); 1518 if (iocb->aio_flags & IOCB_FLAG_RESFD 1452 if (iocb->aio_flags & IOCB_FLAG_RESFD) 1519 req->ki_flags |= IOCB_EVENTFD 1453 req->ki_flags |= IOCB_EVENTFD; >> 1454 req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp)); 1520 if (iocb->aio_flags & IOCB_FLAG_IOPRI 1455 if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { 1521 /* 1456 /* 1522 * If the IOCB_FLAG_IOPRIO fl 1457 * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, then 1523 * aio_reqprio is interpreted 1458 * aio_reqprio is interpreted as an I/O scheduling 1524 * class and priority. 1459 * class and priority. 1525 */ 1460 */ 1526 ret = ioprio_check_cap(iocb-> 1461 ret = ioprio_check_cap(iocb->aio_reqprio); 1527 if (ret) { 1462 if (ret) { 1528 pr_debug("aio ioprio 1463 pr_debug("aio ioprio check cap error: %d\n", ret); 1529 return ret; 1464 return ret; 1530 } 1465 } 1531 1466 1532 req->ki_ioprio = iocb->aio_re 1467 req->ki_ioprio = iocb->aio_reqprio; 1533 } else 1468 } else 1534 req->ki_ioprio = get_current_ 1469 req->ki_ioprio = get_current_ioprio(); 1535 1470 1536 ret = kiocb_set_rw_flags(req, iocb->a !! 1471 ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags); 1537 if (unlikely(ret)) 1472 if (unlikely(ret)) 1538 return ret; 1473 return ret; 1539 1474 1540 req->ki_flags &= ~IOCB_HIPRI; /* no o 1475 req->ki_flags &= ~IOCB_HIPRI; /* no one is going to poll for this I/O */ 1541 return 0; 1476 return 0; 1542 } 1477 } 1543 1478 1544 static ssize_t aio_setup_rw(int rw, const str 1479 static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, 1545 struct iovec **iovec, bool ve 1480 struct iovec **iovec, bool vectored, bool compat, 1546 struct iov_iter *iter) 1481 struct iov_iter *iter) 1547 { 1482 { 1548 void __user *buf = (void __user *)(ui 1483 void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; 1549 size_t len = iocb->aio_nbytes; 1484 size_t len = iocb->aio_nbytes; 1550 1485 1551 if (!vectored) { 1486 if (!vectored) { 1552 ssize_t ret = import_ubuf(rw, !! 1487 ssize_t ret = import_single_range(rw, buf, len, *iovec, iter); 1553 *iovec = NULL; 1488 *iovec = NULL; 1554 return ret; 1489 return ret; 1555 } 1490 } 1556 1491 1557 return __import_iovec(rw, buf, len, U 1492 return __import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter, compat); 1558 } 1493 } 1559 1494 1560 static inline void aio_rw_done(struct kiocb * 1495 static inline void aio_rw_done(struct kiocb *req, ssize_t ret) 1561 { 1496 { 1562 switch (ret) { 1497 switch (ret) { 1563 case -EIOCBQUEUED: 1498 case -EIOCBQUEUED: 1564 break; 1499 break; 1565 case -ERESTARTSYS: 1500 case -ERESTARTSYS: 1566 case -ERESTARTNOINTR: 1501 case -ERESTARTNOINTR: 1567 case -ERESTARTNOHAND: 1502 case -ERESTARTNOHAND: 1568 case -ERESTART_RESTARTBLOCK: 1503 case -ERESTART_RESTARTBLOCK: 1569 /* 1504 /* 1570 * There's no easy way to res 1505 * There's no easy way to restart the syscall since other AIO's 1571 * may be already running. Ju 1506 * may be already running. Just fail this IO with EINTR. 1572 */ 1507 */ 1573 ret = -EINTR; 1508 ret = -EINTR; 1574 fallthrough; 1509 fallthrough; 1575 default: 1510 default: 1576 req->ki_complete(req, ret); !! 1511 req->ki_complete(req, ret, 0); 1577 } 1512 } 1578 } 1513 } 1579 1514 1580 static int aio_read(struct kiocb *req, const 1515 static int aio_read(struct kiocb *req, const struct iocb *iocb, 1581 bool vectored, bool c 1516 bool vectored, bool compat) 1582 { 1517 { 1583 struct iovec inline_vecs[UIO_FASTIOV] 1518 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; 1584 struct iov_iter iter; 1519 struct iov_iter iter; 1585 struct file *file; 1520 struct file *file; 1586 int ret; 1521 int ret; 1587 1522 1588 ret = aio_prep_rw(req, iocb, READ); !! 1523 ret = aio_prep_rw(req, iocb); 1589 if (ret) 1524 if (ret) 1590 return ret; 1525 return ret; 1591 file = req->ki_filp; 1526 file = req->ki_filp; 1592 if (unlikely(!(file->f_mode & FMODE_R 1527 if (unlikely(!(file->f_mode & FMODE_READ))) 1593 return -EBADF; 1528 return -EBADF; >> 1529 ret = -EINVAL; 1594 if (unlikely(!file->f_op->read_iter)) 1530 if (unlikely(!file->f_op->read_iter)) 1595 return -EINVAL; 1531 return -EINVAL; 1596 1532 1597 ret = aio_setup_rw(ITER_DEST, iocb, & !! 1533 ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter); 1598 if (ret < 0) 1534 if (ret < 0) 1599 return ret; 1535 return ret; 1600 ret = rw_verify_area(READ, file, &req 1536 ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); 1601 if (!ret) 1537 if (!ret) 1602 aio_rw_done(req, file->f_op-> !! 1538 aio_rw_done(req, call_read_iter(file, req, &iter)); 1603 kfree(iovec); 1539 kfree(iovec); 1604 return ret; 1540 return ret; 1605 } 1541 } 1606 1542 1607 static int aio_write(struct kiocb *req, const 1543 static int aio_write(struct kiocb *req, const struct iocb *iocb, 1608 bool vectored, bool 1544 bool vectored, bool compat) 1609 { 1545 { 1610 struct iovec inline_vecs[UIO_FASTIOV] 1546 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; 1611 struct iov_iter iter; 1547 struct iov_iter iter; 1612 struct file *file; 1548 struct file *file; 1613 int ret; 1549 int ret; 1614 1550 1615 ret = aio_prep_rw(req, iocb, WRITE); !! 1551 ret = aio_prep_rw(req, iocb); 1616 if (ret) 1552 if (ret) 1617 return ret; 1553 return ret; 1618 file = req->ki_filp; 1554 file = req->ki_filp; 1619 1555 1620 if (unlikely(!(file->f_mode & FMODE_W 1556 if (unlikely(!(file->f_mode & FMODE_WRITE))) 1621 return -EBADF; 1557 return -EBADF; 1622 if (unlikely(!file->f_op->write_iter) 1558 if (unlikely(!file->f_op->write_iter)) 1623 return -EINVAL; 1559 return -EINVAL; 1624 1560 1625 ret = aio_setup_rw(ITER_SOURCE, iocb, !! 1561 ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter); 1626 if (ret < 0) 1562 if (ret < 0) 1627 return ret; 1563 return ret; 1628 ret = rw_verify_area(WRITE, file, &re 1564 ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); 1629 if (!ret) { 1565 if (!ret) { 1630 if (S_ISREG(file_inode(file)- !! 1566 /* 1631 kiocb_start_write(req !! 1567 * Open-code file_start_write here to grab freeze protection, >> 1568 * which will be released by another thread in >> 1569 * aio_complete_rw(). Fool lockdep by telling it the lock got >> 1570 * released so that it doesn't complain about the held lock when >> 1571 * we return to userspace. >> 1572 */ >> 1573 if (S_ISREG(file_inode(file)->i_mode)) { >> 1574 sb_start_write(file_inode(file)->i_sb); >> 1575 __sb_writers_release(file_inode(file)->i_sb, SB_FREEZE_WRITE); >> 1576 } 1632 req->ki_flags |= IOCB_WRITE; 1577 req->ki_flags |= IOCB_WRITE; 1633 aio_rw_done(req, file->f_op-> !! 1578 aio_rw_done(req, call_write_iter(file, req, &iter)); 1634 } 1579 } 1635 kfree(iovec); 1580 kfree(iovec); 1636 return ret; 1581 return ret; 1637 } 1582 } 1638 1583 1639 static void aio_fsync_work(struct work_struct 1584 static void aio_fsync_work(struct work_struct *work) 1640 { 1585 { 1641 struct aio_kiocb *iocb = container_of 1586 struct aio_kiocb *iocb = container_of(work, struct aio_kiocb, fsync.work); 1642 const struct cred *old_cred = overrid 1587 const struct cred *old_cred = override_creds(iocb->fsync.creds); 1643 1588 1644 iocb->ki_res.res = vfs_fsync(iocb->fs 1589 iocb->ki_res.res = vfs_fsync(iocb->fsync.file, iocb->fsync.datasync); 1645 revert_creds(old_cred); 1590 revert_creds(old_cred); 1646 put_cred(iocb->fsync.creds); 1591 put_cred(iocb->fsync.creds); 1647 iocb_put(iocb); 1592 iocb_put(iocb); 1648 } 1593 } 1649 1594 1650 static int aio_fsync(struct fsync_iocb *req, 1595 static int aio_fsync(struct fsync_iocb *req, const struct iocb *iocb, 1651 bool datasync) 1596 bool datasync) 1652 { 1597 { 1653 if (unlikely(iocb->aio_buf || iocb->a 1598 if (unlikely(iocb->aio_buf || iocb->aio_offset || iocb->aio_nbytes || 1654 iocb->aio_rw_flags)) 1599 iocb->aio_rw_flags)) 1655 return -EINVAL; 1600 return -EINVAL; 1656 1601 1657 if (unlikely(!req->file->f_op->fsync) 1602 if (unlikely(!req->file->f_op->fsync)) 1658 return -EINVAL; 1603 return -EINVAL; 1659 1604 1660 req->creds = prepare_creds(); 1605 req->creds = prepare_creds(); 1661 if (!req->creds) 1606 if (!req->creds) 1662 return -ENOMEM; 1607 return -ENOMEM; 1663 1608 1664 req->datasync = datasync; 1609 req->datasync = datasync; 1665 INIT_WORK(&req->work, aio_fsync_work) 1610 INIT_WORK(&req->work, aio_fsync_work); 1666 schedule_work(&req->work); 1611 schedule_work(&req->work); 1667 return 0; 1612 return 0; 1668 } 1613 } 1669 1614 1670 static void aio_poll_put_work(struct work_str 1615 static void aio_poll_put_work(struct work_struct *work) 1671 { 1616 { 1672 struct poll_iocb *req = container_of( 1617 struct poll_iocb *req = container_of(work, struct poll_iocb, work); 1673 struct aio_kiocb *iocb = container_of 1618 struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); 1674 1619 1675 iocb_put(iocb); 1620 iocb_put(iocb); 1676 } 1621 } 1677 1622 1678 /* << 1679 * Safely lock the waitqueue which the reques << 1680 * case where the ->poll() provider decides t << 1681 * << 1682 * Returns true on success, meaning that req- << 1683 * is on req->head, and an RCU read lock was << 1684 * request was already removed from its waitq << 1685 */ << 1686 static bool poll_iocb_lock_wq(struct poll_ioc << 1687 { << 1688 wait_queue_head_t *head; << 1689 << 1690 /* << 1691 * While we hold the waitqueue lock a << 1692 * wake_up_pollfree() will wait for u << 1693 * lock in the first place can race w << 1694 * << 1695 * We solve this as eventpoll does: b << 1696 * all users of wake_up_pollfree() wi << 1697 * we enter rcu_read_lock() and see t << 1698 * non-NULL, we can then lock it with << 1699 * under us, then check whether the r << 1700 * << 1701 * Keep holding rcu_read_lock() as lo << 1702 * case the caller deletes the entry << 1703 * In that case, only RCU prevents th << 1704 */ << 1705 rcu_read_lock(); << 1706 head = smp_load_acquire(&req->head); << 1707 if (head) { << 1708 spin_lock(&head->lock); << 1709 if (!list_empty(&req->wait.en << 1710 return true; << 1711 spin_unlock(&head->lock); << 1712 } << 1713 rcu_read_unlock(); << 1714 return false; << 1715 } << 1716 << 1717 static void poll_iocb_unlock_wq(struct poll_i << 1718 { << 1719 spin_unlock(&req->head->lock); << 1720 rcu_read_unlock(); << 1721 } << 1722 << 1723 static void aio_poll_complete_work(struct wor 1623 static void aio_poll_complete_work(struct work_struct *work) 1724 { 1624 { 1725 struct poll_iocb *req = container_of( 1625 struct poll_iocb *req = container_of(work, struct poll_iocb, work); 1726 struct aio_kiocb *iocb = container_of 1626 struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); 1727 struct poll_table_struct pt = { ._key 1627 struct poll_table_struct pt = { ._key = req->events }; 1728 struct kioctx *ctx = iocb->ki_ctx; 1628 struct kioctx *ctx = iocb->ki_ctx; 1729 __poll_t mask = 0; 1629 __poll_t mask = 0; 1730 1630 1731 if (!READ_ONCE(req->cancelled)) 1631 if (!READ_ONCE(req->cancelled)) 1732 mask = vfs_poll(req->file, &p 1632 mask = vfs_poll(req->file, &pt) & req->events; 1733 1633 1734 /* 1634 /* 1735 * Note that ->ki_cancel callers also 1635 * Note that ->ki_cancel callers also delete iocb from active_reqs after 1736 * calling ->ki_cancel. We need the 1636 * calling ->ki_cancel. We need the ctx_lock roundtrip here to 1737 * synchronize with them. In the can 1637 * synchronize with them. In the cancellation case the list_del_init 1738 * itself is not actually needed, but 1638 * itself is not actually needed, but harmless so we keep it in to 1739 * avoid further branches in the fast 1639 * avoid further branches in the fast path. 1740 */ 1640 */ 1741 spin_lock_irq(&ctx->ctx_lock); 1641 spin_lock_irq(&ctx->ctx_lock); 1742 if (poll_iocb_lock_wq(req)) { !! 1642 if (!mask && !READ_ONCE(req->cancelled)) { 1743 if (!mask && !READ_ONCE(req-> !! 1643 add_wait_queue(req->head, &req->wait); 1744 /* !! 1644 spin_unlock_irq(&ctx->ctx_lock); 1745 * The request isn't !! 1645 return; 1746 * Reschedule complet !! 1646 } 1747 */ << 1748 if (req->work_need_re << 1749 schedule_work << 1750 req->work_nee << 1751 } else { << 1752 req->work_sch << 1753 } << 1754 poll_iocb_unlock_wq(r << 1755 spin_unlock_irq(&ctx- << 1756 return; << 1757 } << 1758 list_del_init(&req->wait.entr << 1759 poll_iocb_unlock_wq(req); << 1760 } /* else, POLLFREE has freed the wai << 1761 list_del_init(&iocb->ki_list); 1647 list_del_init(&iocb->ki_list); 1762 iocb->ki_res.res = mangle_poll(mask); 1648 iocb->ki_res.res = mangle_poll(mask); >> 1649 req->done = true; 1763 spin_unlock_irq(&ctx->ctx_lock); 1650 spin_unlock_irq(&ctx->ctx_lock); 1764 1651 1765 iocb_put(iocb); 1652 iocb_put(iocb); 1766 } 1653 } 1767 1654 1768 /* assumes we are called with irqs disabled * 1655 /* assumes we are called with irqs disabled */ 1769 static int aio_poll_cancel(struct kiocb *iocb 1656 static int aio_poll_cancel(struct kiocb *iocb) 1770 { 1657 { 1771 struct aio_kiocb *aiocb = container_o 1658 struct aio_kiocb *aiocb = container_of(iocb, struct aio_kiocb, rw); 1772 struct poll_iocb *req = &aiocb->poll; 1659 struct poll_iocb *req = &aiocb->poll; 1773 1660 1774 if (poll_iocb_lock_wq(req)) { !! 1661 spin_lock(&req->head->lock); 1775 WRITE_ONCE(req->cancelled, tr !! 1662 WRITE_ONCE(req->cancelled, true); 1776 if (!req->work_scheduled) { !! 1663 if (!list_empty(&req->wait.entry)) { 1777 schedule_work(&aiocb- !! 1664 list_del_init(&req->wait.entry); 1778 req->work_scheduled = !! 1665 schedule_work(&aiocb->poll.work); 1779 } !! 1666 } 1780 poll_iocb_unlock_wq(req); !! 1667 spin_unlock(&req->head->lock); 1781 } /* else, the request was force-canc << 1782 1668 1783 return 0; 1669 return 0; 1784 } 1670 } 1785 1671 1786 static int aio_poll_wake(struct wait_queue_en 1672 static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, 1787 void *key) 1673 void *key) 1788 { 1674 { 1789 struct poll_iocb *req = container_of( 1675 struct poll_iocb *req = container_of(wait, struct poll_iocb, wait); 1790 struct aio_kiocb *iocb = container_of 1676 struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); 1791 __poll_t mask = key_to_poll(key); 1677 __poll_t mask = key_to_poll(key); 1792 unsigned long flags; 1678 unsigned long flags; 1793 1679 1794 /* for instances that support it chec 1680 /* for instances that support it check for an event match first: */ 1795 if (mask && !(mask & req->events)) 1681 if (mask && !(mask & req->events)) 1796 return 0; 1682 return 0; 1797 1683 1798 /* !! 1684 list_del_init(&req->wait.entry); 1799 * Complete the request inline if pos !! 1685 1800 * conditions be met: !! 1686 if (mask && spin_trylock_irqsave(&iocb->ki_ctx->ctx_lock, flags)) { 1801 * 1. An event mask must have been << 1802 * instead, then mask == 0 and w << 1803 * the events, so inline complet << 1804 * 2. The completion work must not << 1805 * 3. ctx_lock must not be busy. W << 1806 * already hold the waitqueue lo << 1807 * locking order. Use irqsave/i << 1808 * filesystems (e.g. fuse) call << 1809 * yet IRQs have to be disabled << 1810 */ << 1811 if (mask && !req->work_scheduled && << 1812 spin_trylock_irqsave(&iocb->ki_ct << 1813 struct kioctx *ctx = iocb->ki 1687 struct kioctx *ctx = iocb->ki_ctx; 1814 1688 1815 list_del_init(&req->wait.entr !! 1689 /* >> 1690 * Try to complete the iocb inline if we can. Use >> 1691 * irqsave/irqrestore because not all filesystems (e.g. fuse) >> 1692 * call this function with IRQs disabled and because IRQs >> 1693 * have to be disabled before ctx_lock is obtained. >> 1694 */ 1816 list_del(&iocb->ki_list); 1695 list_del(&iocb->ki_list); 1817 iocb->ki_res.res = mangle_pol 1696 iocb->ki_res.res = mangle_poll(mask); 1818 if (iocb->ki_eventfd && !even !! 1697 req->done = true; >> 1698 if (iocb->ki_eventfd && eventfd_signal_count()) { 1819 iocb = NULL; 1699 iocb = NULL; 1820 INIT_WORK(&req->work, 1700 INIT_WORK(&req->work, aio_poll_put_work); 1821 schedule_work(&req->w 1701 schedule_work(&req->work); 1822 } 1702 } 1823 spin_unlock_irqrestore(&ctx-> 1703 spin_unlock_irqrestore(&ctx->ctx_lock, flags); 1824 if (iocb) 1704 if (iocb) 1825 iocb_put(iocb); 1705 iocb_put(iocb); 1826 } else { 1706 } else { 1827 /* !! 1707 schedule_work(&req->work); 1828 * Schedule the completion wo << 1829 * scheduled, record that ano << 1830 * << 1831 * Don't remove the request f << 1832 * not actually be complete y << 1833 * is called), and we must no << 1834 * exception to this; see bel << 1835 */ << 1836 if (req->work_scheduled) { << 1837 req->work_need_resche << 1838 } else { << 1839 schedule_work(&req->w << 1840 req->work_scheduled = << 1841 } << 1842 << 1843 /* << 1844 * If the waitqueue is being << 1845 * the request inline, we hav << 1846 * we can. That means immedi << 1847 * waitqueue and preventing a << 1848 * waitqueue via the request. << 1849 * completion work (done abov << 1850 * cancelled, to potentially << 1851 */ << 1852 if (mask & POLLFREE) { << 1853 WRITE_ONCE(req->cance << 1854 list_del_init(&req->w << 1855 << 1856 /* << 1857 * Careful: this *mus << 1858 * as req->head is NU << 1859 * completed and free << 1860 * will no longer nee << 1861 */ << 1862 smp_store_release(&re << 1863 } << 1864 } 1708 } 1865 return 1; 1709 return 1; 1866 } 1710 } 1867 1711 1868 struct aio_poll_table { 1712 struct aio_poll_table { 1869 struct poll_table_struct pt; 1713 struct poll_table_struct pt; 1870 struct aio_kiocb *iocb 1714 struct aio_kiocb *iocb; 1871 bool queue << 1872 int error 1715 int error; 1873 }; 1716 }; 1874 1717 1875 static void 1718 static void 1876 aio_poll_queue_proc(struct file *file, struct 1719 aio_poll_queue_proc(struct file *file, struct wait_queue_head *head, 1877 struct poll_table_struct *p) 1720 struct poll_table_struct *p) 1878 { 1721 { 1879 struct aio_poll_table *pt = container 1722 struct aio_poll_table *pt = container_of(p, struct aio_poll_table, pt); 1880 1723 1881 /* multiple wait queues per file are 1724 /* multiple wait queues per file are not supported */ 1882 if (unlikely(pt->queued)) { !! 1725 if (unlikely(pt->iocb->poll.head)) { 1883 pt->error = -EINVAL; 1726 pt->error = -EINVAL; 1884 return; 1727 return; 1885 } 1728 } 1886 1729 1887 pt->queued = true; << 1888 pt->error = 0; 1730 pt->error = 0; 1889 pt->iocb->poll.head = head; 1731 pt->iocb->poll.head = head; 1890 add_wait_queue(head, &pt->iocb->poll. 1732 add_wait_queue(head, &pt->iocb->poll.wait); 1891 } 1733 } 1892 1734 1893 static int aio_poll(struct aio_kiocb *aiocb, 1735 static int aio_poll(struct aio_kiocb *aiocb, const struct iocb *iocb) 1894 { 1736 { 1895 struct kioctx *ctx = aiocb->ki_ctx; 1737 struct kioctx *ctx = aiocb->ki_ctx; 1896 struct poll_iocb *req = &aiocb->poll; 1738 struct poll_iocb *req = &aiocb->poll; 1897 struct aio_poll_table apt; 1739 struct aio_poll_table apt; 1898 bool cancel = false; 1740 bool cancel = false; 1899 __poll_t mask; 1741 __poll_t mask; 1900 1742 1901 /* reject any unknown events outside 1743 /* reject any unknown events outside the normal event mask. */ 1902 if ((u16)iocb->aio_buf != iocb->aio_b 1744 if ((u16)iocb->aio_buf != iocb->aio_buf) 1903 return -EINVAL; 1745 return -EINVAL; 1904 /* reject fields that are not defined 1746 /* reject fields that are not defined for poll */ 1905 if (iocb->aio_offset || iocb->aio_nby 1747 if (iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags) 1906 return -EINVAL; 1748 return -EINVAL; 1907 1749 1908 INIT_WORK(&req->work, aio_poll_comple 1750 INIT_WORK(&req->work, aio_poll_complete_work); 1909 req->events = demangle_poll(iocb->aio 1751 req->events = demangle_poll(iocb->aio_buf) | EPOLLERR | EPOLLHUP; 1910 1752 1911 req->head = NULL; 1753 req->head = NULL; >> 1754 req->done = false; 1912 req->cancelled = false; 1755 req->cancelled = false; 1913 req->work_scheduled = false; << 1914 req->work_need_resched = false; << 1915 1756 1916 apt.pt._qproc = aio_poll_queue_proc; 1757 apt.pt._qproc = aio_poll_queue_proc; 1917 apt.pt._key = req->events; 1758 apt.pt._key = req->events; 1918 apt.iocb = aiocb; 1759 apt.iocb = aiocb; 1919 apt.queued = false; << 1920 apt.error = -EINVAL; /* same as no su 1760 apt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ 1921 1761 1922 /* initialized the list so that we ca 1762 /* initialized the list so that we can do list_empty checks */ 1923 INIT_LIST_HEAD(&req->wait.entry); 1763 INIT_LIST_HEAD(&req->wait.entry); 1924 init_waitqueue_func_entry(&req->wait, 1764 init_waitqueue_func_entry(&req->wait, aio_poll_wake); 1925 1765 1926 mask = vfs_poll(req->file, &apt.pt) & 1766 mask = vfs_poll(req->file, &apt.pt) & req->events; 1927 spin_lock_irq(&ctx->ctx_lock); 1767 spin_lock_irq(&ctx->ctx_lock); 1928 if (likely(apt.queued)) { !! 1768 if (likely(req->head)) { 1929 bool on_queue = poll_iocb_loc !! 1769 spin_lock(&req->head->lock); 1930 !! 1770 if (unlikely(list_empty(&req->wait.entry))) { 1931 if (!on_queue || req->work_sc !! 1771 if (apt.error) 1932 /* << 1933 * aio_poll_wake() al << 1934 * completion work, o << 1935 */ << 1936 if (apt.error) /* uns << 1937 cancel = true 1772 cancel = true; 1938 apt.error = 0; 1773 apt.error = 0; 1939 mask = 0; 1774 mask = 0; 1940 } 1775 } 1941 if (mask || apt.error) { 1776 if (mask || apt.error) { 1942 /* Steal to complete << 1943 list_del_init(&req->w 1777 list_del_init(&req->wait.entry); 1944 } else if (cancel) { 1778 } else if (cancel) { 1945 /* Cancel if possible << 1946 WRITE_ONCE(req->cance 1779 WRITE_ONCE(req->cancelled, true); 1947 } else if (on_queue) { !! 1780 } else if (!req->done) { /* actually waiting for an event */ 1948 /* << 1949 * Actually waiting f << 1950 * active_reqs so tha << 1951 */ << 1952 list_add_tail(&aiocb- 1781 list_add_tail(&aiocb->ki_list, &ctx->active_reqs); 1953 aiocb->ki_cancel = ai 1782 aiocb->ki_cancel = aio_poll_cancel; 1954 } 1783 } 1955 if (on_queue) !! 1784 spin_unlock(&req->head->lock); 1956 poll_iocb_unlock_wq(r << 1957 } 1785 } 1958 if (mask) { /* no async, we'd stolen 1786 if (mask) { /* no async, we'd stolen it */ 1959 aiocb->ki_res.res = mangle_po 1787 aiocb->ki_res.res = mangle_poll(mask); 1960 apt.error = 0; 1788 apt.error = 0; 1961 } 1789 } 1962 spin_unlock_irq(&ctx->ctx_lock); 1790 spin_unlock_irq(&ctx->ctx_lock); 1963 if (mask) 1791 if (mask) 1964 iocb_put(aiocb); 1792 iocb_put(aiocb); 1965 return apt.error; 1793 return apt.error; 1966 } 1794 } 1967 1795 1968 static int __io_submit_one(struct kioctx *ctx 1796 static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, 1969 struct iocb __user 1797 struct iocb __user *user_iocb, struct aio_kiocb *req, 1970 bool compat) 1798 bool compat) 1971 { 1799 { 1972 req->ki_filp = fget(iocb->aio_fildes) 1800 req->ki_filp = fget(iocb->aio_fildes); 1973 if (unlikely(!req->ki_filp)) 1801 if (unlikely(!req->ki_filp)) 1974 return -EBADF; 1802 return -EBADF; 1975 1803 1976 if (iocb->aio_flags & IOCB_FLAG_RESFD 1804 if (iocb->aio_flags & IOCB_FLAG_RESFD) { 1977 struct eventfd_ctx *eventfd; 1805 struct eventfd_ctx *eventfd; 1978 /* 1806 /* 1979 * If the IOCB_FLAG_RESFD fla 1807 * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an 1980 * instance of the file* now. 1808 * instance of the file* now. The file descriptor must be 1981 * an eventfd() fd, and will 1809 * an eventfd() fd, and will be signaled for each completed 1982 * event using the eventfd_si 1810 * event using the eventfd_signal() function. 1983 */ 1811 */ 1984 eventfd = eventfd_ctx_fdget(i 1812 eventfd = eventfd_ctx_fdget(iocb->aio_resfd); 1985 if (IS_ERR(eventfd)) 1813 if (IS_ERR(eventfd)) 1986 return PTR_ERR(eventf 1814 return PTR_ERR(eventfd); 1987 1815 1988 req->ki_eventfd = eventfd; 1816 req->ki_eventfd = eventfd; 1989 } 1817 } 1990 1818 1991 if (unlikely(put_user(KIOCB_KEY, &use 1819 if (unlikely(put_user(KIOCB_KEY, &user_iocb->aio_key))) { 1992 pr_debug("EFAULT: aio_key\n") 1820 pr_debug("EFAULT: aio_key\n"); 1993 return -EFAULT; 1821 return -EFAULT; 1994 } 1822 } 1995 1823 1996 req->ki_res.obj = (u64)(unsigned long 1824 req->ki_res.obj = (u64)(unsigned long)user_iocb; 1997 req->ki_res.data = iocb->aio_data; 1825 req->ki_res.data = iocb->aio_data; 1998 req->ki_res.res = 0; 1826 req->ki_res.res = 0; 1999 req->ki_res.res2 = 0; 1827 req->ki_res.res2 = 0; 2000 1828 2001 switch (iocb->aio_lio_opcode) { 1829 switch (iocb->aio_lio_opcode) { 2002 case IOCB_CMD_PREAD: 1830 case IOCB_CMD_PREAD: 2003 return aio_read(&req->rw, ioc 1831 return aio_read(&req->rw, iocb, false, compat); 2004 case IOCB_CMD_PWRITE: 1832 case IOCB_CMD_PWRITE: 2005 return aio_write(&req->rw, io 1833 return aio_write(&req->rw, iocb, false, compat); 2006 case IOCB_CMD_PREADV: 1834 case IOCB_CMD_PREADV: 2007 return aio_read(&req->rw, ioc 1835 return aio_read(&req->rw, iocb, true, compat); 2008 case IOCB_CMD_PWRITEV: 1836 case IOCB_CMD_PWRITEV: 2009 return aio_write(&req->rw, io 1837 return aio_write(&req->rw, iocb, true, compat); 2010 case IOCB_CMD_FSYNC: 1838 case IOCB_CMD_FSYNC: 2011 return aio_fsync(&req->fsync, 1839 return aio_fsync(&req->fsync, iocb, false); 2012 case IOCB_CMD_FDSYNC: 1840 case IOCB_CMD_FDSYNC: 2013 return aio_fsync(&req->fsync, 1841 return aio_fsync(&req->fsync, iocb, true); 2014 case IOCB_CMD_POLL: 1842 case IOCB_CMD_POLL: 2015 return aio_poll(req, iocb); 1843 return aio_poll(req, iocb); 2016 default: 1844 default: 2017 pr_debug("invalid aio operati 1845 pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode); 2018 return -EINVAL; 1846 return -EINVAL; 2019 } 1847 } 2020 } 1848 } 2021 1849 2022 static int io_submit_one(struct kioctx *ctx, 1850 static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, 2023 bool compat) 1851 bool compat) 2024 { 1852 { 2025 struct aio_kiocb *req; 1853 struct aio_kiocb *req; 2026 struct iocb iocb; 1854 struct iocb iocb; 2027 int err; 1855 int err; 2028 1856 2029 if (unlikely(copy_from_user(&iocb, us 1857 if (unlikely(copy_from_user(&iocb, user_iocb, sizeof(iocb)))) 2030 return -EFAULT; 1858 return -EFAULT; 2031 1859 2032 /* enforce forwards compatibility on 1860 /* enforce forwards compatibility on users */ 2033 if (unlikely(iocb.aio_reserved2)) { 1861 if (unlikely(iocb.aio_reserved2)) { 2034 pr_debug("EINVAL: reserve fie 1862 pr_debug("EINVAL: reserve field set\n"); 2035 return -EINVAL; 1863 return -EINVAL; 2036 } 1864 } 2037 1865 2038 /* prevent overflows */ 1866 /* prevent overflows */ 2039 if (unlikely( 1867 if (unlikely( 2040 (iocb.aio_buf != (unsigned long)i 1868 (iocb.aio_buf != (unsigned long)iocb.aio_buf) || 2041 (iocb.aio_nbytes != (size_t)iocb. 1869 (iocb.aio_nbytes != (size_t)iocb.aio_nbytes) || 2042 ((ssize_t)iocb.aio_nbytes < 0) 1870 ((ssize_t)iocb.aio_nbytes < 0) 2043 )) { 1871 )) { 2044 pr_debug("EINVAL: overflow ch 1872 pr_debug("EINVAL: overflow check\n"); 2045 return -EINVAL; 1873 return -EINVAL; 2046 } 1874 } 2047 1875 2048 req = aio_get_req(ctx); 1876 req = aio_get_req(ctx); 2049 if (unlikely(!req)) 1877 if (unlikely(!req)) 2050 return -EAGAIN; 1878 return -EAGAIN; 2051 1879 2052 err = __io_submit_one(ctx, &iocb, use 1880 err = __io_submit_one(ctx, &iocb, user_iocb, req, compat); 2053 1881 2054 /* Done with the synchronous referenc 1882 /* Done with the synchronous reference */ 2055 iocb_put(req); 1883 iocb_put(req); 2056 1884 2057 /* 1885 /* 2058 * If err is 0, we'd either done aio_ 1886 * If err is 0, we'd either done aio_complete() ourselves or have 2059 * arranged for that to be done async 1887 * arranged for that to be done asynchronously. Anything non-zero 2060 * means that we need to destroy req 1888 * means that we need to destroy req ourselves. 2061 */ 1889 */ 2062 if (unlikely(err)) { 1890 if (unlikely(err)) { 2063 iocb_destroy(req); 1891 iocb_destroy(req); 2064 put_reqs_available(ctx, 1); 1892 put_reqs_available(ctx, 1); 2065 } 1893 } 2066 return err; 1894 return err; 2067 } 1895 } 2068 1896 2069 /* sys_io_submit: 1897 /* sys_io_submit: 2070 * Queue the nr iocbs pointed to by iocb 1898 * Queue the nr iocbs pointed to by iocbpp for processing. Returns 2071 * the number of iocbs queued. May retu 1899 * the number of iocbs queued. May return -EINVAL if the aio_context 2072 * specified by ctx_id is invalid, if nr 1900 * specified by ctx_id is invalid, if nr is < 0, if the iocb at 2073 * *iocbpp[0] is not properly initialize 1901 * *iocbpp[0] is not properly initialized, if the operation specified 2074 * is invalid for the file descriptor in 1902 * is invalid for the file descriptor in the iocb. May fail with 2075 * -EFAULT if any of the data structures 1903 * -EFAULT if any of the data structures point to invalid data. May 2076 * fail with -EBADF if the file descript 1904 * fail with -EBADF if the file descriptor specified in the first 2077 * iocb is invalid. May fail with -EAGA 1905 * iocb is invalid. May fail with -EAGAIN if insufficient resources 2078 * are available to queue any iocbs. Wi 1906 * are available to queue any iocbs. Will return 0 if nr is 0. Will 2079 * fail with -ENOSYS if not implemented. 1907 * fail with -ENOSYS if not implemented. 2080 */ 1908 */ 2081 SYSCALL_DEFINE3(io_submit, aio_context_t, ctx 1909 SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr, 2082 struct iocb __user * __user * 1910 struct iocb __user * __user *, iocbpp) 2083 { 1911 { 2084 struct kioctx *ctx; 1912 struct kioctx *ctx; 2085 long ret = 0; 1913 long ret = 0; 2086 int i = 0; 1914 int i = 0; 2087 struct blk_plug plug; 1915 struct blk_plug plug; 2088 1916 2089 if (unlikely(nr < 0)) 1917 if (unlikely(nr < 0)) 2090 return -EINVAL; 1918 return -EINVAL; 2091 1919 2092 ctx = lookup_ioctx(ctx_id); 1920 ctx = lookup_ioctx(ctx_id); 2093 if (unlikely(!ctx)) { 1921 if (unlikely(!ctx)) { 2094 pr_debug("EINVAL: invalid con 1922 pr_debug("EINVAL: invalid context id\n"); 2095 return -EINVAL; 1923 return -EINVAL; 2096 } 1924 } 2097 1925 2098 if (nr > ctx->nr_events) 1926 if (nr > ctx->nr_events) 2099 nr = ctx->nr_events; 1927 nr = ctx->nr_events; 2100 1928 2101 if (nr > AIO_PLUG_THRESHOLD) 1929 if (nr > AIO_PLUG_THRESHOLD) 2102 blk_start_plug(&plug); 1930 blk_start_plug(&plug); 2103 for (i = 0; i < nr; i++) { 1931 for (i = 0; i < nr; i++) { 2104 struct iocb __user *user_iocb 1932 struct iocb __user *user_iocb; 2105 1933 2106 if (unlikely(get_user(user_io 1934 if (unlikely(get_user(user_iocb, iocbpp + i))) { 2107 ret = -EFAULT; 1935 ret = -EFAULT; 2108 break; 1936 break; 2109 } 1937 } 2110 1938 2111 ret = io_submit_one(ctx, user 1939 ret = io_submit_one(ctx, user_iocb, false); 2112 if (ret) 1940 if (ret) 2113 break; 1941 break; 2114 } 1942 } 2115 if (nr > AIO_PLUG_THRESHOLD) 1943 if (nr > AIO_PLUG_THRESHOLD) 2116 blk_finish_plug(&plug); 1944 blk_finish_plug(&plug); 2117 1945 2118 percpu_ref_put(&ctx->users); 1946 percpu_ref_put(&ctx->users); 2119 return i ? i : ret; 1947 return i ? i : ret; 2120 } 1948 } 2121 1949 2122 #ifdef CONFIG_COMPAT 1950 #ifdef CONFIG_COMPAT 2123 COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_ 1951 COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id, 2124 int, nr, compat_uptr_t 1952 int, nr, compat_uptr_t __user *, iocbpp) 2125 { 1953 { 2126 struct kioctx *ctx; 1954 struct kioctx *ctx; 2127 long ret = 0; 1955 long ret = 0; 2128 int i = 0; 1956 int i = 0; 2129 struct blk_plug plug; 1957 struct blk_plug plug; 2130 1958 2131 if (unlikely(nr < 0)) 1959 if (unlikely(nr < 0)) 2132 return -EINVAL; 1960 return -EINVAL; 2133 1961 2134 ctx = lookup_ioctx(ctx_id); 1962 ctx = lookup_ioctx(ctx_id); 2135 if (unlikely(!ctx)) { 1963 if (unlikely(!ctx)) { 2136 pr_debug("EINVAL: invalid con 1964 pr_debug("EINVAL: invalid context id\n"); 2137 return -EINVAL; 1965 return -EINVAL; 2138 } 1966 } 2139 1967 2140 if (nr > ctx->nr_events) 1968 if (nr > ctx->nr_events) 2141 nr = ctx->nr_events; 1969 nr = ctx->nr_events; 2142 1970 2143 if (nr > AIO_PLUG_THRESHOLD) 1971 if (nr > AIO_PLUG_THRESHOLD) 2144 blk_start_plug(&plug); 1972 blk_start_plug(&plug); 2145 for (i = 0; i < nr; i++) { 1973 for (i = 0; i < nr; i++) { 2146 compat_uptr_t user_iocb; 1974 compat_uptr_t user_iocb; 2147 1975 2148 if (unlikely(get_user(user_io 1976 if (unlikely(get_user(user_iocb, iocbpp + i))) { 2149 ret = -EFAULT; 1977 ret = -EFAULT; 2150 break; 1978 break; 2151 } 1979 } 2152 1980 2153 ret = io_submit_one(ctx, comp 1981 ret = io_submit_one(ctx, compat_ptr(user_iocb), true); 2154 if (ret) 1982 if (ret) 2155 break; 1983 break; 2156 } 1984 } 2157 if (nr > AIO_PLUG_THRESHOLD) 1985 if (nr > AIO_PLUG_THRESHOLD) 2158 blk_finish_plug(&plug); 1986 blk_finish_plug(&plug); 2159 1987 2160 percpu_ref_put(&ctx->users); 1988 percpu_ref_put(&ctx->users); 2161 return i ? i : ret; 1989 return i ? i : ret; 2162 } 1990 } 2163 #endif 1991 #endif 2164 1992 2165 /* sys_io_cancel: 1993 /* sys_io_cancel: 2166 * Attempts to cancel an iocb previously 1994 * Attempts to cancel an iocb previously passed to io_submit. If 2167 * the operation is successfully cancell 1995 * the operation is successfully cancelled, the resulting event is 2168 * copied into the memory pointed to by 1996 * copied into the memory pointed to by result without being placed 2169 * into the completion queue and 0 is re 1997 * into the completion queue and 0 is returned. May fail with 2170 * -EFAULT if any of the data structures 1998 * -EFAULT if any of the data structures pointed to are invalid. 2171 * May fail with -EINVAL if aio_context 1999 * May fail with -EINVAL if aio_context specified by ctx_id is 2172 * invalid. May fail with -EAGAIN if th 2000 * invalid. May fail with -EAGAIN if the iocb specified was not 2173 * cancelled. Will fail with -ENOSYS if 2001 * cancelled. Will fail with -ENOSYS if not implemented. 2174 */ 2002 */ 2175 SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx 2003 SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, 2176 struct io_event __user *, res 2004 struct io_event __user *, result) 2177 { 2005 { 2178 struct kioctx *ctx; 2006 struct kioctx *ctx; 2179 struct aio_kiocb *kiocb; 2007 struct aio_kiocb *kiocb; 2180 int ret = -EINVAL; 2008 int ret = -EINVAL; 2181 u32 key; 2009 u32 key; 2182 u64 obj = (u64)(unsigned long)iocb; 2010 u64 obj = (u64)(unsigned long)iocb; 2183 2011 2184 if (unlikely(get_user(key, &iocb->aio 2012 if (unlikely(get_user(key, &iocb->aio_key))) 2185 return -EFAULT; 2013 return -EFAULT; 2186 if (unlikely(key != KIOCB_KEY)) 2014 if (unlikely(key != KIOCB_KEY)) 2187 return -EINVAL; 2015 return -EINVAL; 2188 2016 2189 ctx = lookup_ioctx(ctx_id); 2017 ctx = lookup_ioctx(ctx_id); 2190 if (unlikely(!ctx)) 2018 if (unlikely(!ctx)) 2191 return -EINVAL; 2019 return -EINVAL; 2192 2020 2193 spin_lock_irq(&ctx->ctx_lock); 2021 spin_lock_irq(&ctx->ctx_lock); 2194 /* TODO: use a hash or array, this su 2022 /* TODO: use a hash or array, this sucks. */ 2195 list_for_each_entry(kiocb, &ctx->acti 2023 list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) { 2196 if (kiocb->ki_res.obj == obj) 2024 if (kiocb->ki_res.obj == obj) { 2197 ret = kiocb->ki_cance 2025 ret = kiocb->ki_cancel(&kiocb->rw); 2198 list_del_init(&kiocb- 2026 list_del_init(&kiocb->ki_list); 2199 break; 2027 break; 2200 } 2028 } 2201 } 2029 } 2202 spin_unlock_irq(&ctx->ctx_lock); 2030 spin_unlock_irq(&ctx->ctx_lock); 2203 2031 2204 if (!ret) { 2032 if (!ret) { 2205 /* 2033 /* 2206 * The result argument is no 2034 * The result argument is no longer used - the io_event is 2207 * always delivered via the r 2035 * always delivered via the ring buffer. -EINPROGRESS indicates 2208 * cancellation is progress: 2036 * cancellation is progress: 2209 */ 2037 */ 2210 ret = -EINPROGRESS; 2038 ret = -EINPROGRESS; 2211 } 2039 } 2212 2040 2213 percpu_ref_put(&ctx->users); 2041 percpu_ref_put(&ctx->users); 2214 2042 2215 return ret; 2043 return ret; 2216 } 2044 } 2217 2045 2218 static long do_io_getevents(aio_context_t ctx 2046 static long do_io_getevents(aio_context_t ctx_id, 2219 long min_nr, 2047 long min_nr, 2220 long nr, 2048 long nr, 2221 struct io_event __user *event 2049 struct io_event __user *events, 2222 struct timespec64 *ts) 2050 struct timespec64 *ts) 2223 { 2051 { 2224 ktime_t until = ts ? timespec64_to_kt 2052 ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX; 2225 struct kioctx *ioctx = lookup_ioctx(c 2053 struct kioctx *ioctx = lookup_ioctx(ctx_id); 2226 long ret = -EINVAL; 2054 long ret = -EINVAL; 2227 2055 2228 if (likely(ioctx)) { 2056 if (likely(ioctx)) { 2229 if (likely(min_nr <= nr && mi 2057 if (likely(min_nr <= nr && min_nr >= 0)) 2230 ret = read_events(ioc 2058 ret = read_events(ioctx, min_nr, nr, events, until); 2231 percpu_ref_put(&ioctx->users) 2059 percpu_ref_put(&ioctx->users); 2232 } 2060 } 2233 2061 2234 return ret; 2062 return ret; 2235 } 2063 } 2236 2064 2237 /* io_getevents: 2065 /* io_getevents: 2238 * Attempts to read at least min_nr even 2066 * Attempts to read at least min_nr events and up to nr events from 2239 * the completion queue for the aio_cont 2067 * the completion queue for the aio_context specified by ctx_id. If 2240 * it succeeds, the number of read event 2068 * it succeeds, the number of read events is returned. May fail with 2241 * -EINVAL if ctx_id is invalid, if min_ 2069 * -EINVAL if ctx_id is invalid, if min_nr is out of range, if nr is 2242 * out of range, if timeout is out of ra 2070 * out of range, if timeout is out of range. May fail with -EFAULT 2243 * if any of the memory specified is inv 2071 * if any of the memory specified is invalid. May return 0 or 2244 * < min_nr if the timeout specified by 2072 * < min_nr if the timeout specified by timeout has elapsed 2245 * before sufficient events are availabl 2073 * before sufficient events are available, where timeout == NULL 2246 * specifies an infinite timeout. Note t 2074 * specifies an infinite timeout. Note that the timeout pointed to by 2247 * timeout is relative. Will fail with 2075 * timeout is relative. Will fail with -ENOSYS if not implemented. 2248 */ 2076 */ 2249 #ifdef CONFIG_64BIT 2077 #ifdef CONFIG_64BIT 2250 2078 2251 SYSCALL_DEFINE5(io_getevents, aio_context_t, 2079 SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id, 2252 long, min_nr, 2080 long, min_nr, 2253 long, nr, 2081 long, nr, 2254 struct io_event __user *, eve 2082 struct io_event __user *, events, 2255 struct __kernel_timespec __us 2083 struct __kernel_timespec __user *, timeout) 2256 { 2084 { 2257 struct timespec64 ts; 2085 struct timespec64 ts; 2258 int ret; 2086 int ret; 2259 2087 2260 if (timeout && unlikely(get_timespec6 2088 if (timeout && unlikely(get_timespec64(&ts, timeout))) 2261 return -EFAULT; 2089 return -EFAULT; 2262 2090 2263 ret = do_io_getevents(ctx_id, min_nr, 2091 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); 2264 if (!ret && signal_pending(current)) 2092 if (!ret && signal_pending(current)) 2265 ret = -EINTR; 2093 ret = -EINTR; 2266 return ret; 2094 return ret; 2267 } 2095 } 2268 2096 2269 #endif 2097 #endif 2270 2098 2271 struct __aio_sigset { 2099 struct __aio_sigset { 2272 const sigset_t __user *sigmask; 2100 const sigset_t __user *sigmask; 2273 size_t sigsetsize; 2101 size_t sigsetsize; 2274 }; 2102 }; 2275 2103 2276 SYSCALL_DEFINE6(io_pgetevents, 2104 SYSCALL_DEFINE6(io_pgetevents, 2277 aio_context_t, ctx_id, 2105 aio_context_t, ctx_id, 2278 long, min_nr, 2106 long, min_nr, 2279 long, nr, 2107 long, nr, 2280 struct io_event __user *, eve 2108 struct io_event __user *, events, 2281 struct __kernel_timespec __us 2109 struct __kernel_timespec __user *, timeout, 2282 const struct __aio_sigset __u 2110 const struct __aio_sigset __user *, usig) 2283 { 2111 { 2284 struct __aio_sigset ksig = { NULL 2112 struct __aio_sigset ksig = { NULL, }; 2285 struct timespec64 ts; 2113 struct timespec64 ts; 2286 bool interrupted; 2114 bool interrupted; 2287 int ret; 2115 int ret; 2288 2116 2289 if (timeout && unlikely(get_timespec6 2117 if (timeout && unlikely(get_timespec64(&ts, timeout))) 2290 return -EFAULT; 2118 return -EFAULT; 2291 2119 2292 if (usig && copy_from_user(&ksig, usi 2120 if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) 2293 return -EFAULT; 2121 return -EFAULT; 2294 2122 2295 ret = set_user_sigmask(ksig.sigmask, 2123 ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); 2296 if (ret) 2124 if (ret) 2297 return ret; 2125 return ret; 2298 2126 2299 ret = do_io_getevents(ctx_id, min_nr, 2127 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); 2300 2128 2301 interrupted = signal_pending(current) 2129 interrupted = signal_pending(current); 2302 restore_saved_sigmask_unless(interrup 2130 restore_saved_sigmask_unless(interrupted); 2303 if (interrupted && !ret) 2131 if (interrupted && !ret) 2304 ret = -ERESTARTNOHAND; 2132 ret = -ERESTARTNOHAND; 2305 2133 2306 return ret; 2134 return ret; 2307 } 2135 } 2308 2136 2309 #if defined(CONFIG_COMPAT_32BIT_TIME) && !def 2137 #if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT) 2310 2138 2311 SYSCALL_DEFINE6(io_pgetevents_time32, 2139 SYSCALL_DEFINE6(io_pgetevents_time32, 2312 aio_context_t, ctx_id, 2140 aio_context_t, ctx_id, 2313 long, min_nr, 2141 long, min_nr, 2314 long, nr, 2142 long, nr, 2315 struct io_event __user *, eve 2143 struct io_event __user *, events, 2316 struct old_timespec32 __user 2144 struct old_timespec32 __user *, timeout, 2317 const struct __aio_sigset __u 2145 const struct __aio_sigset __user *, usig) 2318 { 2146 { 2319 struct __aio_sigset ksig = { NULL 2147 struct __aio_sigset ksig = { NULL, }; 2320 struct timespec64 ts; 2148 struct timespec64 ts; 2321 bool interrupted; 2149 bool interrupted; 2322 int ret; 2150 int ret; 2323 2151 2324 if (timeout && unlikely(get_old_times 2152 if (timeout && unlikely(get_old_timespec32(&ts, timeout))) 2325 return -EFAULT; 2153 return -EFAULT; 2326 2154 2327 if (usig && copy_from_user(&ksig, usi 2155 if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) 2328 return -EFAULT; 2156 return -EFAULT; 2329 2157 2330 2158 2331 ret = set_user_sigmask(ksig.sigmask, 2159 ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); 2332 if (ret) 2160 if (ret) 2333 return ret; 2161 return ret; 2334 2162 2335 ret = do_io_getevents(ctx_id, min_nr, 2163 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); 2336 2164 2337 interrupted = signal_pending(current) 2165 interrupted = signal_pending(current); 2338 restore_saved_sigmask_unless(interrup 2166 restore_saved_sigmask_unless(interrupted); 2339 if (interrupted && !ret) 2167 if (interrupted && !ret) 2340 ret = -ERESTARTNOHAND; 2168 ret = -ERESTARTNOHAND; 2341 2169 2342 return ret; 2170 return ret; 2343 } 2171 } 2344 2172 2345 #endif 2173 #endif 2346 2174 2347 #if defined(CONFIG_COMPAT_32BIT_TIME) 2175 #if defined(CONFIG_COMPAT_32BIT_TIME) 2348 2176 2349 SYSCALL_DEFINE5(io_getevents_time32, __u32, c 2177 SYSCALL_DEFINE5(io_getevents_time32, __u32, ctx_id, 2350 __s32, min_nr, 2178 __s32, min_nr, 2351 __s32, nr, 2179 __s32, nr, 2352 struct io_event __user *, eve 2180 struct io_event __user *, events, 2353 struct old_timespec32 __user 2181 struct old_timespec32 __user *, timeout) 2354 { 2182 { 2355 struct timespec64 t; 2183 struct timespec64 t; 2356 int ret; 2184 int ret; 2357 2185 2358 if (timeout && get_old_timespec32(&t, 2186 if (timeout && get_old_timespec32(&t, timeout)) 2359 return -EFAULT; 2187 return -EFAULT; 2360 2188 2361 ret = do_io_getevents(ctx_id, min_nr, 2189 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); 2362 if (!ret && signal_pending(current)) 2190 if (!ret && signal_pending(current)) 2363 ret = -EINTR; 2191 ret = -EINTR; 2364 return ret; 2192 return ret; 2365 } 2193 } 2366 2194 2367 #endif 2195 #endif 2368 2196 2369 #ifdef CONFIG_COMPAT 2197 #ifdef CONFIG_COMPAT 2370 2198 2371 struct __compat_aio_sigset { 2199 struct __compat_aio_sigset { 2372 compat_uptr_t sigmask; 2200 compat_uptr_t sigmask; 2373 compat_size_t sigsetsize; 2201 compat_size_t sigsetsize; 2374 }; 2202 }; 2375 2203 2376 #if defined(CONFIG_COMPAT_32BIT_TIME) 2204 #if defined(CONFIG_COMPAT_32BIT_TIME) 2377 2205 2378 COMPAT_SYSCALL_DEFINE6(io_pgetevents, 2206 COMPAT_SYSCALL_DEFINE6(io_pgetevents, 2379 compat_aio_context_t, ctx_id, 2207 compat_aio_context_t, ctx_id, 2380 compat_long_t, min_nr, 2208 compat_long_t, min_nr, 2381 compat_long_t, nr, 2209 compat_long_t, nr, 2382 struct io_event __user *, eve 2210 struct io_event __user *, events, 2383 struct old_timespec32 __user 2211 struct old_timespec32 __user *, timeout, 2384 const struct __compat_aio_sig 2212 const struct __compat_aio_sigset __user *, usig) 2385 { 2213 { 2386 struct __compat_aio_sigset ksig = { 0 2214 struct __compat_aio_sigset ksig = { 0, }; 2387 struct timespec64 t; 2215 struct timespec64 t; 2388 bool interrupted; 2216 bool interrupted; 2389 int ret; 2217 int ret; 2390 2218 2391 if (timeout && get_old_timespec32(&t, 2219 if (timeout && get_old_timespec32(&t, timeout)) 2392 return -EFAULT; 2220 return -EFAULT; 2393 2221 2394 if (usig && copy_from_user(&ksig, usi 2222 if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) 2395 return -EFAULT; 2223 return -EFAULT; 2396 2224 2397 ret = set_compat_user_sigmask(compat_ 2225 ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); 2398 if (ret) 2226 if (ret) 2399 return ret; 2227 return ret; 2400 2228 2401 ret = do_io_getevents(ctx_id, min_nr, 2229 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); 2402 2230 2403 interrupted = signal_pending(current) 2231 interrupted = signal_pending(current); 2404 restore_saved_sigmask_unless(interrup 2232 restore_saved_sigmask_unless(interrupted); 2405 if (interrupted && !ret) 2233 if (interrupted && !ret) 2406 ret = -ERESTARTNOHAND; 2234 ret = -ERESTARTNOHAND; 2407 2235 2408 return ret; 2236 return ret; 2409 } 2237 } 2410 2238 2411 #endif 2239 #endif 2412 2240 2413 COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64, 2241 COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64, 2414 compat_aio_context_t, ctx_id, 2242 compat_aio_context_t, ctx_id, 2415 compat_long_t, min_nr, 2243 compat_long_t, min_nr, 2416 compat_long_t, nr, 2244 compat_long_t, nr, 2417 struct io_event __user *, eve 2245 struct io_event __user *, events, 2418 struct __kernel_timespec __us 2246 struct __kernel_timespec __user *, timeout, 2419 const struct __compat_aio_sig 2247 const struct __compat_aio_sigset __user *, usig) 2420 { 2248 { 2421 struct __compat_aio_sigset ksig = { 0 2249 struct __compat_aio_sigset ksig = { 0, }; 2422 struct timespec64 t; 2250 struct timespec64 t; 2423 bool interrupted; 2251 bool interrupted; 2424 int ret; 2252 int ret; 2425 2253 2426 if (timeout && get_timespec64(&t, tim 2254 if (timeout && get_timespec64(&t, timeout)) 2427 return -EFAULT; 2255 return -EFAULT; 2428 2256 2429 if (usig && copy_from_user(&ksig, usi 2257 if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) 2430 return -EFAULT; 2258 return -EFAULT; 2431 2259 2432 ret = set_compat_user_sigmask(compat_ 2260 ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); 2433 if (ret) 2261 if (ret) 2434 return ret; 2262 return ret; 2435 2263 2436 ret = do_io_getevents(ctx_id, min_nr, 2264 ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); 2437 2265 2438 interrupted = signal_pending(current) 2266 interrupted = signal_pending(current); 2439 restore_saved_sigmask_unless(interrup 2267 restore_saved_sigmask_unless(interrupted); 2440 if (interrupted && !ret) 2268 if (interrupted && !ret) 2441 ret = -ERESTARTNOHAND; 2269 ret = -ERESTARTNOHAND; 2442 2270 2443 return ret; 2271 return ret; 2444 } 2272 } 2445 #endif 2273 #endif 2446 2274
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