1 /* SPDX-License-Identifier: GPL-2.0-only */ <<
2 /* 1 /*
3 * Copyright (C) 2003 Sistina Software 2 * Copyright (C) 2003 Sistina Software
4 * Copyright (C) 2004 - 2008 Red Hat, Inc. All 3 * Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved.
5 * 4 *
6 * Device-Mapper low-level I/O. 5 * Device-Mapper low-level I/O.
7 * 6 *
8 * This file is released under the GPL. 7 * This file is released under the GPL.
9 */ 8 */
10 9
11 #ifndef _LINUX_DM_IO_H 10 #ifndef _LINUX_DM_IO_H
12 #define _LINUX_DM_IO_H 11 #define _LINUX_DM_IO_H
13 12
14 #ifdef __KERNEL__ 13 #ifdef __KERNEL__
15 14
16 #include <linux/types.h> 15 #include <linux/types.h>
17 #include <linux/blk_types.h> <<
18 16
19 struct dm_io_region { 17 struct dm_io_region {
20 struct block_device *bdev; 18 struct block_device *bdev;
21 sector_t sector; 19 sector_t sector;
22 sector_t count; /* If this is 20 sector_t count; /* If this is zero the region is ignored. */
23 }; 21 };
24 22
25 struct page_list { 23 struct page_list {
26 struct page_list *next; 24 struct page_list *next;
27 struct page *page; 25 struct page *page;
28 }; 26 };
29 27
30 typedef void (*io_notify_fn)(unsigned int long !! 28 typedef void (*io_notify_fn)(unsigned long error, void *context);
31 29
32 enum dm_io_mem_type { 30 enum dm_io_mem_type {
33 DM_IO_PAGE_LIST,/* Page list */ 31 DM_IO_PAGE_LIST,/* Page list */
34 DM_IO_BIO, /* Bio vector */ 32 DM_IO_BIO, /* Bio vector */
35 DM_IO_VMA, /* Virtual memory area 33 DM_IO_VMA, /* Virtual memory area */
36 DM_IO_KMEM, /* Kernel memory */ 34 DM_IO_KMEM, /* Kernel memory */
37 }; 35 };
38 36
39 struct dm_io_memory { 37 struct dm_io_memory {
40 enum dm_io_mem_type type; 38 enum dm_io_mem_type type;
41 39
42 unsigned int offset; !! 40 unsigned offset;
43 41
44 union { 42 union {
45 struct page_list *pl; 43 struct page_list *pl;
46 struct bio *bio; 44 struct bio *bio;
47 void *vma; 45 void *vma;
48 void *addr; 46 void *addr;
49 } ptr; 47 } ptr;
50 }; 48 };
51 49
52 struct dm_io_notify { 50 struct dm_io_notify {
53 io_notify_fn fn; /* Callback fo 51 io_notify_fn fn; /* Callback for asynchronous requests */
54 void *context; /* Passed to c 52 void *context; /* Passed to callback */
55 }; 53 };
56 54
57 /* 55 /*
58 * IO request structure 56 * IO request structure
59 */ 57 */
60 struct dm_io_client; 58 struct dm_io_client;
61 struct dm_io_request { 59 struct dm_io_request {
62 blk_opf_t bi_opf; /* Req !! 60 int bi_rw; /* READ|WRITE - not READA */
63 struct dm_io_memory mem; /* Mem 61 struct dm_io_memory mem; /* Memory to use for io */
64 struct dm_io_notify notify; /* Syn 62 struct dm_io_notify notify; /* Synchronous if notify.fn is NULL */
65 struct dm_io_client *client; /* Cli 63 struct dm_io_client *client; /* Client memory handler */
66 }; 64 };
67 65
68 /* 66 /*
69 * For async io calls, users can alternatively 67 * For async io calls, users can alternatively use the dm_io() function below
70 * and dm_io_client_create() to create private 68 * and dm_io_client_create() to create private mempools for the client.
71 * 69 *
72 * Create/destroy may block. 70 * Create/destroy may block.
73 */ 71 */
74 struct dm_io_client *dm_io_client_create(void) 72 struct dm_io_client *dm_io_client_create(void);
75 void dm_io_client_destroy(struct dm_io_client 73 void dm_io_client_destroy(struct dm_io_client *client);
76 74
77 /* 75 /*
78 * IO interface using private per-client pools 76 * IO interface using private per-client pools.
79 * Each bit in the optional 'sync_error_bits' 77 * Each bit in the optional 'sync_error_bits' bitset indicates whether an
80 * error occurred doing io to the correspondin 78 * error occurred doing io to the corresponding region.
81 */ 79 */
82 int dm_io(struct dm_io_request *io_req, unsign !! 80 int dm_io(struct dm_io_request *io_req, unsigned num_regions,
83 struct dm_io_region *region, unsigne !! 81 struct dm_io_region *region, unsigned long *sync_error_bits);
84 unsigned short ioprio); <<
85 82
86 #endif /* __KERNEL__ */ 83 #endif /* __KERNEL__ */
87 #endif /* _LINUX_DM_IO_H */ 84 #endif /* _LINUX_DM_IO_H */
88 85
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