1 // SPDX-License-Identifier: GPL-2.0-or-later 1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* 2 /*
3 * locks.c 3 * locks.c
4 * 4 *
5 * Userspace file locking support 5 * Userspace file locking support
6 * 6 *
7 * Copyright (C) 2007 Oracle. All rights rese 7 * Copyright (C) 2007 Oracle. All rights reserved.
8 */ 8 */
9 9
10 #include <linux/fs.h> 10 #include <linux/fs.h>
11 #include <linux/filelock.h> 11 #include <linux/filelock.h>
12 #include <linux/fcntl.h> 12 #include <linux/fcntl.h>
13 13
14 #include <cluster/masklog.h> 14 #include <cluster/masklog.h>
15 15
16 #include "ocfs2.h" 16 #include "ocfs2.h"
17 17
18 #include "dlmglue.h" 18 #include "dlmglue.h"
19 #include "file.h" 19 #include "file.h"
20 #include "inode.h" 20 #include "inode.h"
21 #include "locks.h" 21 #include "locks.h"
22 22
23 static int ocfs2_do_flock(struct file *file, s 23 static int ocfs2_do_flock(struct file *file, struct inode *inode,
24 int cmd, struct file 24 int cmd, struct file_lock *fl)
25 { 25 {
26 int ret = 0, level = 0, trylock = 0; 26 int ret = 0, level = 0, trylock = 0;
27 struct ocfs2_file_private *fp = file-> 27 struct ocfs2_file_private *fp = file->private_data;
28 struct ocfs2_lock_res *lockres = &fp-> 28 struct ocfs2_lock_res *lockres = &fp->fp_flock;
29 29
30 if (lock_is_write(fl)) 30 if (lock_is_write(fl))
31 level = 1; 31 level = 1;
32 if (!IS_SETLKW(cmd)) 32 if (!IS_SETLKW(cmd))
33 trylock = 1; 33 trylock = 1;
34 34
35 mutex_lock(&fp->fp_mutex); 35 mutex_lock(&fp->fp_mutex);
36 36
37 if (lockres->l_flags & OCFS2_LOCK_ATTA 37 if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
38 lockres->l_level > LKM_NLMODE) { 38 lockres->l_level > LKM_NLMODE) {
39 int old_level = 0; 39 int old_level = 0;
40 struct file_lock request; 40 struct file_lock request;
41 41
42 if (lockres->l_level == LKM_EX 42 if (lockres->l_level == LKM_EXMODE)
43 old_level = 1; 43 old_level = 1;
44 44
45 if (level == old_level) 45 if (level == old_level)
46 goto out; 46 goto out;
47 47
48 /* 48 /*
49 * Converting an existing lock 49 * Converting an existing lock is not guaranteed to be
50 * atomic, so we can get away 50 * atomic, so we can get away with simply unlocking
51 * here and allowing the lock 51 * here and allowing the lock code to try at the new
52 * level. 52 * level.
53 */ 53 */
54 54
55 locks_init_lock(&request); 55 locks_init_lock(&request);
56 request.c.flc_type = F_UNLCK; 56 request.c.flc_type = F_UNLCK;
57 request.c.flc_flags = FL_FLOCK 57 request.c.flc_flags = FL_FLOCK;
58 locks_lock_file_wait(file, &re 58 locks_lock_file_wait(file, &request);
59 59
60 ocfs2_file_unlock(file); 60 ocfs2_file_unlock(file);
61 } 61 }
62 62
63 ret = ocfs2_file_lock(file, level, try 63 ret = ocfs2_file_lock(file, level, trylock);
64 if (ret) { 64 if (ret) {
65 if (ret == -EAGAIN && trylock) 65 if (ret == -EAGAIN && trylock)
66 ret = -EWOULDBLOCK; 66 ret = -EWOULDBLOCK;
67 else 67 else
68 mlog_errno(ret); 68 mlog_errno(ret);
69 goto out; 69 goto out;
70 } 70 }
71 71
72 ret = locks_lock_file_wait(file, fl); 72 ret = locks_lock_file_wait(file, fl);
73 if (ret) 73 if (ret)
74 ocfs2_file_unlock(file); 74 ocfs2_file_unlock(file);
75 75
76 out: 76 out:
77 mutex_unlock(&fp->fp_mutex); 77 mutex_unlock(&fp->fp_mutex);
78 78
79 return ret; 79 return ret;
80 } 80 }
81 81
82 static int ocfs2_do_funlock(struct file *file, 82 static int ocfs2_do_funlock(struct file *file, int cmd, struct file_lock *fl)
83 { 83 {
84 int ret; 84 int ret;
85 struct ocfs2_file_private *fp = file-> 85 struct ocfs2_file_private *fp = file->private_data;
86 86
87 mutex_lock(&fp->fp_mutex); 87 mutex_lock(&fp->fp_mutex);
88 ocfs2_file_unlock(file); 88 ocfs2_file_unlock(file);
89 ret = locks_lock_file_wait(file, fl); 89 ret = locks_lock_file_wait(file, fl);
90 mutex_unlock(&fp->fp_mutex); 90 mutex_unlock(&fp->fp_mutex);
91 91
92 return ret; 92 return ret;
93 } 93 }
94 94
95 /* 95 /*
96 * Overall flow of ocfs2_flock() was influence 96 * Overall flow of ocfs2_flock() was influenced by gfs2_flock().
97 */ 97 */
98 int ocfs2_flock(struct file *file, int cmd, st 98 int ocfs2_flock(struct file *file, int cmd, struct file_lock *fl)
99 { 99 {
100 struct inode *inode = file->f_mapping- 100 struct inode *inode = file->f_mapping->host;
101 struct ocfs2_super *osb = OCFS2_SB(ino 101 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
102 102
103 if (!(fl->c.flc_flags & FL_FLOCK)) 103 if (!(fl->c.flc_flags & FL_FLOCK))
104 return -ENOLCK; 104 return -ENOLCK;
105 105
106 if ((osb->s_mount_opt & OCFS2_MOUNT_LO 106 if ((osb->s_mount_opt & OCFS2_MOUNT_LOCALFLOCKS) ||
107 ocfs2_mount_local(osb)) 107 ocfs2_mount_local(osb))
108 return locks_lock_file_wait(fi 108 return locks_lock_file_wait(file, fl);
109 109
110 if (lock_is_unlock(fl)) 110 if (lock_is_unlock(fl))
111 return ocfs2_do_funlock(file, 111 return ocfs2_do_funlock(file, cmd, fl);
112 else 112 else
113 return ocfs2_do_flock(file, in 113 return ocfs2_do_flock(file, inode, cmd, fl);
114 } 114 }
115 115
116 int ocfs2_lock(struct file *file, int cmd, str 116 int ocfs2_lock(struct file *file, int cmd, struct file_lock *fl)
117 { 117 {
118 struct inode *inode = file->f_mapping- 118 struct inode *inode = file->f_mapping->host;
119 struct ocfs2_super *osb = OCFS2_SB(ino 119 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
120 120
121 if (!(fl->c.flc_flags & FL_POSIX)) 121 if (!(fl->c.flc_flags & FL_POSIX))
122 return -ENOLCK; 122 return -ENOLCK;
123 123
124 return ocfs2_plock(osb->cconn, OCFS2_I 124 return ocfs2_plock(osb->cconn, OCFS2_I(inode)->ip_blkno, file, cmd, fl);
125 } 125 }
126 126
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