1 #include <linux/ceph/ceph_debug.h>
3 #include <linux/file.h>
4 #include <linux/namei.h>
5 #include <linux/random.h>
8 #include "mds_client.h"
9 #include <linux/ceph/pagelist.h>
11 static u64 lock_secret;
13 static inline u64 secure_addr(void *addr)
15 u64 v = lock_secret ^ (u64)(unsigned long)addr;
17 * Set the most significant bit, so that MDS knows the 'owner'
18 * is sufficient to identify the owner of lock. (old code uses
19 * both 'owner' and 'pid')
25 void __init ceph_flock_init(void)
27 get_random_bytes(&lock_secret, sizeof(lock_secret));
31 * Implement fcntl and flock locking functions.
33 static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
34 int cmd, u8 wait, struct file_lock *fl)
36 struct inode *inode = file_inode(file);
37 struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
38 struct ceph_mds_request *req;
43 req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
50 /* mds requires start and length rather than start and end */
51 if (LLONG_MAX == fl->fl_end)
54 length = fl->fl_end - fl->fl_start + 1;
56 if (lock_type == CEPH_LOCK_FCNTL)
57 owner = secure_addr(fl->fl_owner);
59 owner = secure_addr(fl->fl_file);
61 dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
62 "start: %llu, length: %llu, wait: %d, type: %d", (int)lock_type,
63 (int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
66 req->r_args.filelock_change.rule = lock_type;
67 req->r_args.filelock_change.type = cmd;
68 req->r_args.filelock_change.owner = cpu_to_le64(owner);
69 req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
70 req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
71 req->r_args.filelock_change.length = cpu_to_le64(length);
72 req->r_args.filelock_change.wait = wait;
74 err = ceph_mdsc_do_request(mdsc, inode, req);
76 if (operation == CEPH_MDS_OP_GETFILELOCK) {
77 fl->fl_pid = le64_to_cpu(req->r_reply_info.filelock_reply->pid);
78 if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
79 fl->fl_type = F_RDLCK;
80 else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
81 fl->fl_type = F_WRLCK;
83 fl->fl_type = F_UNLCK;
85 fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
86 length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
87 le64_to_cpu(req->r_reply_info.filelock_reply->length);
89 fl->fl_end = length -1;
94 ceph_mdsc_put_request(req);
95 dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
96 "length: %llu, wait: %d, type: %d, err code %d", (int)lock_type,
97 (int)operation, (u64)fl->fl_pid, fl->fl_start,
98 length, wait, fl->fl_type, err);
103 * Attempt to set an fcntl lock.
104 * For now, this just goes away to the server. Later it may be more awesome.
106 int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
111 u16 op = CEPH_MDS_OP_SETFILELOCK;
113 if (!(fl->fl_flags & FL_POSIX))
115 /* No mandatory locks */
116 if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
119 dout("ceph_lock, fl_owner: %p", fl->fl_owner);
121 /* set wait bit as appropriate, then make command as Ceph expects it*/
123 op = CEPH_MDS_OP_GETFILELOCK;
124 else if (IS_SETLKW(cmd))
127 if (F_RDLCK == fl->fl_type)
128 lock_cmd = CEPH_LOCK_SHARED;
129 else if (F_WRLCK == fl->fl_type)
130 lock_cmd = CEPH_LOCK_EXCL;
132 lock_cmd = CEPH_LOCK_UNLOCK;
134 err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file, lock_cmd, wait, fl);
136 if (op != CEPH_MDS_OP_GETFILELOCK) {
137 dout("mds locked, locking locally");
138 err = posix_lock_file(file, fl, NULL);
139 if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
140 /* undo! This should only happen if
141 * the kernel detects local
143 ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
144 CEPH_LOCK_UNLOCK, 0, fl);
145 dout("got %d on posix_lock_file, undid lock",
150 } else if (err == -ERESTARTSYS) {
151 dout("undoing lock\n");
152 ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
153 CEPH_LOCK_UNLOCK, 0, fl);
158 int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
164 if (!(fl->fl_flags & FL_FLOCK))
166 /* No mandatory locks */
167 if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
170 dout("ceph_flock, fl_file: %p", fl->fl_file);
175 if (F_RDLCK == fl->fl_type)
176 lock_cmd = CEPH_LOCK_SHARED;
177 else if (F_WRLCK == fl->fl_type)
178 lock_cmd = CEPH_LOCK_EXCL;
180 lock_cmd = CEPH_LOCK_UNLOCK;
182 err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
183 file, lock_cmd, wait, fl);
185 err = flock_lock_file_wait(file, fl);
187 ceph_lock_message(CEPH_LOCK_FLOCK,
188 CEPH_MDS_OP_SETFILELOCK,
189 file, CEPH_LOCK_UNLOCK, 0, fl);
190 dout("got %d on flock_lock_file_wait, undid lock", err);
192 } else if (err == -ERESTARTSYS) {
193 dout("undoing lock\n");
194 ceph_lock_message(CEPH_LOCK_FLOCK,
195 CEPH_MDS_OP_SETFILELOCK,
196 file, CEPH_LOCK_UNLOCK, 0, fl);
202 * Must be called with lock_flocks() already held. Fills in the passed
203 * counter variables, so you can prepare pagelist metadata before calling
206 void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
208 struct file_lock *lock;
213 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
214 if (lock->fl_flags & FL_POSIX)
216 else if (lock->fl_flags & FL_FLOCK)
219 dout("counted %d flock locks and %d fcntl locks",
220 *flock_count, *fcntl_count);
224 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
225 * array. Must be called with inode->i_lock already held.
226 * If we encounter more of a specific lock type than expected, return -ENOSPC.
228 int ceph_encode_locks_to_buffer(struct inode *inode,
229 struct ceph_filelock *flocks,
230 int num_fcntl_locks, int num_flock_locks)
232 struct file_lock *lock;
238 dout("encoding %d flock and %d fcntl locks", num_flock_locks,
241 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
242 if (lock->fl_flags & FL_POSIX) {
244 if (seen_fcntl > num_fcntl_locks) {
248 err = lock_to_ceph_filelock(lock, &flocks[l]);
254 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
255 if (lock->fl_flags & FL_FLOCK) {
257 if (seen_flock > num_flock_locks) {
261 err = lock_to_ceph_filelock(lock, &flocks[l]);
272 * Copy the encoded flock and fcntl locks into the pagelist.
273 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
274 * sequential flock locks.
275 * Returns zero on success.
277 int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
278 struct ceph_pagelist *pagelist,
279 int num_fcntl_locks, int num_flock_locks)
284 nlocks = cpu_to_le32(num_fcntl_locks);
285 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
289 err = ceph_pagelist_append(pagelist, flocks,
290 num_fcntl_locks * sizeof(*flocks));
294 nlocks = cpu_to_le32(num_flock_locks);
295 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
299 err = ceph_pagelist_append(pagelist,
300 &flocks[num_fcntl_locks],
301 num_flock_locks * sizeof(*flocks));
307 * Given a pointer to a lock, convert it to a ceph filelock
309 int lock_to_ceph_filelock(struct file_lock *lock,
310 struct ceph_filelock *cephlock)
313 cephlock->start = cpu_to_le64(lock->fl_start);
314 cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
315 cephlock->client = cpu_to_le64(0);
316 cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
317 if (lock->fl_flags & FL_POSIX)
318 cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
320 cephlock->owner = cpu_to_le64(secure_addr(lock->fl_file));
322 switch (lock->fl_type) {
324 cephlock->type = CEPH_LOCK_SHARED;
327 cephlock->type = CEPH_LOCK_EXCL;
330 cephlock->type = CEPH_LOCK_UNLOCK;
333 dout("Have unknown lock type %d", lock->fl_type);