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1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/file.h>
4#include <linux/namei.h>
5#include <linux/random.h>
6
7#include "super.h"
8#include "mds_client.h"
9#include <linux/ceph/pagelist.h>
10
11static u64 lock_secret;
12static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
13 struct ceph_mds_request *req);
14
15static inline u64 secure_addr(void *addr)
16{
17 u64 v = lock_secret ^ (u64)(unsigned long)addr;
18 /*
19 * Set the most significant bit, so that MDS knows the 'owner'
20 * is sufficient to identify the owner of lock. (old code uses
21 * both 'owner' and 'pid')
22 */
23 v |= (1ULL << 63);
24 return v;
25}
26
27void __init ceph_flock_init(void)
28{
29 get_random_bytes(&lock_secret, sizeof(lock_secret));
30}
31
32/**
33 * Implement fcntl and flock locking functions.
34 */
35static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
36 int cmd, u8 wait, struct file_lock *fl)
37{
38 struct inode *inode = file_inode(file);
39 struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
40 struct ceph_mds_request *req;
41 int err;
42 u64 length = 0;
43 u64 owner;
44
45 if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK)
46 wait = 0;
47
48 req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
49 if (IS_ERR(req))
50 return PTR_ERR(req);
51 req->r_inode = inode;
52 ihold(inode);
53 req->r_num_caps = 1;
54
55 /* mds requires start and length rather than start and end */
56 if (LLONG_MAX == fl->fl_end)
57 length = 0;
58 else
59 length = fl->fl_end - fl->fl_start + 1;
60
61 owner = secure_addr(fl->fl_owner);
62
63 dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
64 "start: %llu, length: %llu, wait: %d, type: %d", (int)lock_type,
65 (int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
66 wait, fl->fl_type);
67
68 req->r_args.filelock_change.rule = lock_type;
69 req->r_args.filelock_change.type = cmd;
70 req->r_args.filelock_change.owner = cpu_to_le64(owner);
71 req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
72 req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
73 req->r_args.filelock_change.length = cpu_to_le64(length);
74 req->r_args.filelock_change.wait = wait;
75
76 if (wait)
77 req->r_wait_for_completion = ceph_lock_wait_for_completion;
78
79 err = ceph_mdsc_do_request(mdsc, inode, req);
80
81 if (operation == CEPH_MDS_OP_GETFILELOCK) {
82 fl->fl_pid = le64_to_cpu(req->r_reply_info.filelock_reply->pid);
83 if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
84 fl->fl_type = F_RDLCK;
85 else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
86 fl->fl_type = F_WRLCK;
87 else
88 fl->fl_type = F_UNLCK;
89
90 fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
91 length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
92 le64_to_cpu(req->r_reply_info.filelock_reply->length);
93 if (length >= 1)
94 fl->fl_end = length -1;
95 else
96 fl->fl_end = 0;
97
98 }
99 ceph_mdsc_put_request(req);
100 dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
101 "length: %llu, wait: %d, type: %d, err code %d", (int)lock_type,
102 (int)operation, (u64)fl->fl_pid, fl->fl_start,
103 length, wait, fl->fl_type, err);
104 return err;
105}
106
107static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
108 struct ceph_mds_request *req)
109{
110 struct ceph_mds_request *intr_req;
111 struct inode *inode = req->r_inode;
112 int err, lock_type;
113
114 BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
115 if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
116 lock_type = CEPH_LOCK_FCNTL_INTR;
117 else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
118 lock_type = CEPH_LOCK_FLOCK_INTR;
119 else
120 BUG_ON(1);
121 BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);
122
123 err = wait_for_completion_interruptible(&req->r_completion);
124 if (!err)
125 return 0;
126
127 dout("ceph_lock_wait_for_completion: request %llu was interrupted\n",
128 req->r_tid);
129
130 intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
131 USE_AUTH_MDS);
132 if (IS_ERR(intr_req))
133 return PTR_ERR(intr_req);
134
135 intr_req->r_inode = inode;
136 ihold(inode);
137 intr_req->r_num_caps = 1;
138
139 intr_req->r_args.filelock_change = req->r_args.filelock_change;
140 intr_req->r_args.filelock_change.rule = lock_type;
141 intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;
142
143 err = ceph_mdsc_do_request(mdsc, inode, intr_req);
144 ceph_mdsc_put_request(intr_req);
145
146 if (err && err != -ERESTARTSYS)
147 return err;
148
149 wait_for_completion(&req->r_completion);
150 return 0;
151}
152
153/**
154 * Attempt to set an fcntl lock.
155 * For now, this just goes away to the server. Later it may be more awesome.
156 */
157int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
158{
159 u8 lock_cmd;
160 int err;
161 u8 wait = 0;
162 u16 op = CEPH_MDS_OP_SETFILELOCK;
163
164 if (!(fl->fl_flags & FL_POSIX))
165 return -ENOLCK;
166 /* No mandatory locks */
167 if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
168 return -ENOLCK;
169
170 dout("ceph_lock, fl_owner: %p", fl->fl_owner);
171
172 /* set wait bit as appropriate, then make command as Ceph expects it*/
173 if (IS_GETLK(cmd))
174 op = CEPH_MDS_OP_GETFILELOCK;
175 else if (IS_SETLKW(cmd))
176 wait = 1;
177
178 if (F_RDLCK == fl->fl_type)
179 lock_cmd = CEPH_LOCK_SHARED;
180 else if (F_WRLCK == fl->fl_type)
181 lock_cmd = CEPH_LOCK_EXCL;
182 else
183 lock_cmd = CEPH_LOCK_UNLOCK;
184
185 err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file, lock_cmd, wait, fl);
186 if (!err) {
187 if (op != CEPH_MDS_OP_GETFILELOCK) {
188 dout("mds locked, locking locally");
189 err = posix_lock_file(file, fl, NULL);
190 if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
191 /* undo! This should only happen if
192 * the kernel detects local
193 * deadlock. */
194 ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
195 CEPH_LOCK_UNLOCK, 0, fl);
196 dout("got %d on posix_lock_file, undid lock",
197 err);
198 }
199 }
200 }
201 return err;
202}
203
204int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
205{
206 u8 lock_cmd;
207 int err;
208 u8 wait = 0;
209
210 if (!(fl->fl_flags & FL_FLOCK))
211 return -ENOLCK;
212 /* No mandatory locks */
213 if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
214 return -ENOLCK;
215
216 dout("ceph_flock, fl_file: %p", fl->fl_file);
217
218 if (IS_SETLKW(cmd))
219 wait = 1;
220
221 if (F_RDLCK == fl->fl_type)
222 lock_cmd = CEPH_LOCK_SHARED;
223 else if (F_WRLCK == fl->fl_type)
224 lock_cmd = CEPH_LOCK_EXCL;
225 else
226 lock_cmd = CEPH_LOCK_UNLOCK;
227
228 err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
229 file, lock_cmd, wait, fl);
230 if (!err) {
231 err = locks_lock_file_wait(file, fl);
232 if (err) {
233 ceph_lock_message(CEPH_LOCK_FLOCK,
234 CEPH_MDS_OP_SETFILELOCK,
235 file, CEPH_LOCK_UNLOCK, 0, fl);
236 dout("got %d on locks_lock_file_wait, undid lock", err);
237 }
238 }
239 return err;
240}
241
242/*
243 * Fills in the passed counter variables, so you can prepare pagelist metadata
244 * before calling ceph_encode_locks.
245 */
246void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
247{
248 struct file_lock *lock;
249 struct file_lock_context *ctx;
250
251 *fcntl_count = 0;
252 *flock_count = 0;
253
254 ctx = inode->i_flctx;
255 if (ctx) {
256 spin_lock(&ctx->flc_lock);
257 list_for_each_entry(lock, &ctx->flc_posix, fl_list)
258 ++(*fcntl_count);
259 list_for_each_entry(lock, &ctx->flc_flock, fl_list)
260 ++(*flock_count);
261 spin_unlock(&ctx->flc_lock);
262 }
263 dout("counted %d flock locks and %d fcntl locks",
264 *flock_count, *fcntl_count);
265}
266
267/**
268 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
269 * array. Must be called with inode->i_lock already held.
270 * If we encounter more of a specific lock type than expected, return -ENOSPC.
271 */
272int ceph_encode_locks_to_buffer(struct inode *inode,
273 struct ceph_filelock *flocks,
274 int num_fcntl_locks, int num_flock_locks)
275{
276 struct file_lock *lock;
277 struct file_lock_context *ctx = inode->i_flctx;
278 int err = 0;
279 int seen_fcntl = 0;
280 int seen_flock = 0;
281 int l = 0;
282
283 dout("encoding %d flock and %d fcntl locks", num_flock_locks,
284 num_fcntl_locks);
285
286 if (!ctx)
287 return 0;
288
289 spin_lock(&ctx->flc_lock);
290 list_for_each_entry(lock, &ctx->flc_posix, fl_list) {
291 ++seen_fcntl;
292 if (seen_fcntl > num_fcntl_locks) {
293 err = -ENOSPC;
294 goto fail;
295 }
296 err = lock_to_ceph_filelock(lock, &flocks[l]);
297 if (err)
298 goto fail;
299 ++l;
300 }
301 list_for_each_entry(lock, &ctx->flc_flock, fl_list) {
302 ++seen_flock;
303 if (seen_flock > num_flock_locks) {
304 err = -ENOSPC;
305 goto fail;
306 }
307 err = lock_to_ceph_filelock(lock, &flocks[l]);
308 if (err)
309 goto fail;
310 ++l;
311 }
312fail:
313 spin_unlock(&ctx->flc_lock);
314 return err;
315}
316
317/**
318 * Copy the encoded flock and fcntl locks into the pagelist.
319 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
320 * sequential flock locks.
321 * Returns zero on success.
322 */
323int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
324 struct ceph_pagelist *pagelist,
325 int num_fcntl_locks, int num_flock_locks)
326{
327 int err = 0;
328 __le32 nlocks;
329
330 nlocks = cpu_to_le32(num_fcntl_locks);
331 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
332 if (err)
333 goto out_fail;
334
335 err = ceph_pagelist_append(pagelist, flocks,
336 num_fcntl_locks * sizeof(*flocks));
337 if (err)
338 goto out_fail;
339
340 nlocks = cpu_to_le32(num_flock_locks);
341 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
342 if (err)
343 goto out_fail;
344
345 err = ceph_pagelist_append(pagelist,
346 &flocks[num_fcntl_locks],
347 num_flock_locks * sizeof(*flocks));
348out_fail:
349 return err;
350}
351
352/*
353 * Given a pointer to a lock, convert it to a ceph filelock
354 */
355int lock_to_ceph_filelock(struct file_lock *lock,
356 struct ceph_filelock *cephlock)
357{
358 int err = 0;
359 cephlock->start = cpu_to_le64(lock->fl_start);
360 cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
361 cephlock->client = cpu_to_le64(0);
362 cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
363 cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
364
365 switch (lock->fl_type) {
366 case F_RDLCK:
367 cephlock->type = CEPH_LOCK_SHARED;
368 break;
369 case F_WRLCK:
370 cephlock->type = CEPH_LOCK_EXCL;
371 break;
372 case F_UNLCK:
373 cephlock->type = CEPH_LOCK_UNLOCK;
374 break;
375 default:
376 dout("Have unknown lock type %d", lock->fl_type);
377 err = -EINVAL;
378 }
379
380 return err;
381}
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ceph/ceph_debug.h>
3
4#include <linux/file.h>
5#include <linux/namei.h>
6#include <linux/random.h>
7
8#include "super.h"
9#include "mds_client.h"
10#include <linux/ceph/pagelist.h>
11
12static u64 lock_secret;
13static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
14 struct ceph_mds_request *req);
15
16static inline u64 secure_addr(void *addr)
17{
18 u64 v = lock_secret ^ (u64)(unsigned long)addr;
19 /*
20 * Set the most significant bit, so that MDS knows the 'owner'
21 * is sufficient to identify the owner of lock. (old code uses
22 * both 'owner' and 'pid')
23 */
24 v |= (1ULL << 63);
25 return v;
26}
27
28void __init ceph_flock_init(void)
29{
30 get_random_bytes(&lock_secret, sizeof(lock_secret));
31}
32
33static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
34{
35 struct inode *inode = file_inode(dst->fl_file);
36 atomic_inc(&ceph_inode(inode)->i_filelock_ref);
37 dst->fl_u.ceph.inode = igrab(inode);
38}
39
40/*
41 * Do not use the 'fl->fl_file' in release function, which
42 * is possibly already released by another thread.
43 */
44static void ceph_fl_release_lock(struct file_lock *fl)
45{
46 struct inode *inode = fl->fl_u.ceph.inode;
47 struct ceph_inode_info *ci;
48
49 /*
50 * If inode is NULL it should be a request file_lock,
51 * nothing we can do.
52 */
53 if (!inode)
54 return;
55
56 ci = ceph_inode(inode);
57 if (atomic_dec_and_test(&ci->i_filelock_ref)) {
58 /* clear error when all locks are released */
59 spin_lock(&ci->i_ceph_lock);
60 ci->i_ceph_flags &= ~CEPH_I_ERROR_FILELOCK;
61 spin_unlock(&ci->i_ceph_lock);
62 }
63 fl->fl_u.ceph.inode = NULL;
64 iput(inode);
65}
66
67static const struct file_lock_operations ceph_fl_lock_ops = {
68 .fl_copy_lock = ceph_fl_copy_lock,
69 .fl_release_private = ceph_fl_release_lock,
70};
71
72/*
73 * Implement fcntl and flock locking functions.
74 */
75static int ceph_lock_message(u8 lock_type, u16 operation, struct inode *inode,
76 int cmd, u8 wait, struct file_lock *fl)
77{
78 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
79 struct ceph_mds_request *req;
80 int err;
81 u64 length = 0;
82 u64 owner;
83
84 if (operation == CEPH_MDS_OP_SETFILELOCK) {
85 /*
86 * increasing i_filelock_ref closes race window between
87 * handling request reply and adding file_lock struct to
88 * inode. Otherwise, auth caps may get trimmed in the
89 * window. Caller function will decrease the counter.
90 */
91 fl->fl_ops = &ceph_fl_lock_ops;
92 fl->fl_ops->fl_copy_lock(fl, NULL);
93 }
94
95 if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK)
96 wait = 0;
97
98 req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
99 if (IS_ERR(req))
100 return PTR_ERR(req);
101 req->r_inode = inode;
102 ihold(inode);
103 req->r_num_caps = 1;
104
105 /* mds requires start and length rather than start and end */
106 if (LLONG_MAX == fl->fl_end)
107 length = 0;
108 else
109 length = fl->fl_end - fl->fl_start + 1;
110
111 owner = secure_addr(fl->fl_owner);
112
113 dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
114 "start: %llu, length: %llu, wait: %d, type: %d\n", (int)lock_type,
115 (int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
116 wait, fl->fl_type);
117
118 req->r_args.filelock_change.rule = lock_type;
119 req->r_args.filelock_change.type = cmd;
120 req->r_args.filelock_change.owner = cpu_to_le64(owner);
121 req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
122 req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
123 req->r_args.filelock_change.length = cpu_to_le64(length);
124 req->r_args.filelock_change.wait = wait;
125
126 err = ceph_mdsc_submit_request(mdsc, inode, req);
127 if (!err)
128 err = ceph_mdsc_wait_request(mdsc, req, wait ?
129 ceph_lock_wait_for_completion : NULL);
130 if (!err && operation == CEPH_MDS_OP_GETFILELOCK) {
131 fl->fl_pid = -le64_to_cpu(req->r_reply_info.filelock_reply->pid);
132 if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
133 fl->fl_type = F_RDLCK;
134 else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
135 fl->fl_type = F_WRLCK;
136 else
137 fl->fl_type = F_UNLCK;
138
139 fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
140 length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
141 le64_to_cpu(req->r_reply_info.filelock_reply->length);
142 if (length >= 1)
143 fl->fl_end = length -1;
144 else
145 fl->fl_end = 0;
146
147 }
148 ceph_mdsc_put_request(req);
149 dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
150 "length: %llu, wait: %d, type: %d, err code %d\n", (int)lock_type,
151 (int)operation, (u64)fl->fl_pid, fl->fl_start,
152 length, wait, fl->fl_type, err);
153 return err;
154}
155
156static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
157 struct ceph_mds_request *req)
158{
159 struct ceph_mds_request *intr_req;
160 struct inode *inode = req->r_inode;
161 int err, lock_type;
162
163 BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
164 if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
165 lock_type = CEPH_LOCK_FCNTL_INTR;
166 else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
167 lock_type = CEPH_LOCK_FLOCK_INTR;
168 else
169 BUG_ON(1);
170 BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);
171
172 err = wait_for_completion_interruptible(&req->r_completion);
173 if (!err)
174 return 0;
175
176 dout("ceph_lock_wait_for_completion: request %llu was interrupted\n",
177 req->r_tid);
178
179 mutex_lock(&mdsc->mutex);
180 if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
181 err = 0;
182 } else {
183 /*
184 * ensure we aren't running concurrently with
185 * ceph_fill_trace or ceph_readdir_prepopulate, which
186 * rely on locks (dir mutex) held by our caller.
187 */
188 mutex_lock(&req->r_fill_mutex);
189 req->r_err = err;
190 set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
191 mutex_unlock(&req->r_fill_mutex);
192
193 if (!req->r_session) {
194 // haven't sent the request
195 err = 0;
196 }
197 }
198 mutex_unlock(&mdsc->mutex);
199 if (!err)
200 return 0;
201
202 intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
203 USE_AUTH_MDS);
204 if (IS_ERR(intr_req))
205 return PTR_ERR(intr_req);
206
207 intr_req->r_inode = inode;
208 ihold(inode);
209 intr_req->r_num_caps = 1;
210
211 intr_req->r_args.filelock_change = req->r_args.filelock_change;
212 intr_req->r_args.filelock_change.rule = lock_type;
213 intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;
214
215 err = ceph_mdsc_do_request(mdsc, inode, intr_req);
216 ceph_mdsc_put_request(intr_req);
217
218 if (err && err != -ERESTARTSYS)
219 return err;
220
221 wait_for_completion_killable(&req->r_safe_completion);
222 return 0;
223}
224
225static int try_unlock_file(struct file *file, struct file_lock *fl)
226{
227 int err;
228 unsigned int orig_flags = fl->fl_flags;
229 fl->fl_flags |= FL_EXISTS;
230 err = locks_lock_file_wait(file, fl);
231 fl->fl_flags = orig_flags;
232 if (err == -ENOENT) {
233 if (!(orig_flags & FL_EXISTS))
234 err = 0;
235 return err;
236 }
237 return 1;
238}
239
240/*
241 * Attempt to set an fcntl lock.
242 * For now, this just goes away to the server. Later it may be more awesome.
243 */
244int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
245{
246 struct inode *inode = file_inode(file);
247 struct ceph_inode_info *ci = ceph_inode(inode);
248 int err = 0;
249 u16 op = CEPH_MDS_OP_SETFILELOCK;
250 u8 wait = 0;
251 u8 lock_cmd;
252
253 if (!(fl->fl_flags & FL_POSIX))
254 return -ENOLCK;
255
256 if (ceph_inode_is_shutdown(inode))
257 return -ESTALE;
258
259 dout("ceph_lock, fl_owner: %p\n", fl->fl_owner);
260
261 /* set wait bit as appropriate, then make command as Ceph expects it*/
262 if (IS_GETLK(cmd))
263 op = CEPH_MDS_OP_GETFILELOCK;
264 else if (IS_SETLKW(cmd))
265 wait = 1;
266
267 spin_lock(&ci->i_ceph_lock);
268 if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
269 err = -EIO;
270 }
271 spin_unlock(&ci->i_ceph_lock);
272 if (err < 0) {
273 if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type)
274 posix_lock_file(file, fl, NULL);
275 return err;
276 }
277
278 if (F_RDLCK == fl->fl_type)
279 lock_cmd = CEPH_LOCK_SHARED;
280 else if (F_WRLCK == fl->fl_type)
281 lock_cmd = CEPH_LOCK_EXCL;
282 else
283 lock_cmd = CEPH_LOCK_UNLOCK;
284
285 if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type) {
286 err = try_unlock_file(file, fl);
287 if (err <= 0)
288 return err;
289 }
290
291 err = ceph_lock_message(CEPH_LOCK_FCNTL, op, inode, lock_cmd, wait, fl);
292 if (!err) {
293 if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK != fl->fl_type) {
294 dout("mds locked, locking locally\n");
295 err = posix_lock_file(file, fl, NULL);
296 if (err) {
297 /* undo! This should only happen if
298 * the kernel detects local
299 * deadlock. */
300 ceph_lock_message(CEPH_LOCK_FCNTL, op, inode,
301 CEPH_LOCK_UNLOCK, 0, fl);
302 dout("got %d on posix_lock_file, undid lock\n",
303 err);
304 }
305 }
306 }
307 return err;
308}
309
310int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
311{
312 struct inode *inode = file_inode(file);
313 struct ceph_inode_info *ci = ceph_inode(inode);
314 int err = 0;
315 u8 wait = 0;
316 u8 lock_cmd;
317
318 if (!(fl->fl_flags & FL_FLOCK))
319 return -ENOLCK;
320
321 if (ceph_inode_is_shutdown(inode))
322 return -ESTALE;
323
324 dout("ceph_flock, fl_file: %p\n", fl->fl_file);
325
326 spin_lock(&ci->i_ceph_lock);
327 if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
328 err = -EIO;
329 }
330 spin_unlock(&ci->i_ceph_lock);
331 if (err < 0) {
332 if (F_UNLCK == fl->fl_type)
333 locks_lock_file_wait(file, fl);
334 return err;
335 }
336
337 if (IS_SETLKW(cmd))
338 wait = 1;
339
340 if (F_RDLCK == fl->fl_type)
341 lock_cmd = CEPH_LOCK_SHARED;
342 else if (F_WRLCK == fl->fl_type)
343 lock_cmd = CEPH_LOCK_EXCL;
344 else
345 lock_cmd = CEPH_LOCK_UNLOCK;
346
347 if (F_UNLCK == fl->fl_type) {
348 err = try_unlock_file(file, fl);
349 if (err <= 0)
350 return err;
351 }
352
353 err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
354 inode, lock_cmd, wait, fl);
355 if (!err && F_UNLCK != fl->fl_type) {
356 err = locks_lock_file_wait(file, fl);
357 if (err) {
358 ceph_lock_message(CEPH_LOCK_FLOCK,
359 CEPH_MDS_OP_SETFILELOCK,
360 inode, CEPH_LOCK_UNLOCK, 0, fl);
361 dout("got %d on locks_lock_file_wait, undid lock\n", err);
362 }
363 }
364 return err;
365}
366
367/*
368 * Fills in the passed counter variables, so you can prepare pagelist metadata
369 * before calling ceph_encode_locks.
370 */
371void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
372{
373 struct file_lock *lock;
374 struct file_lock_context *ctx;
375
376 *fcntl_count = 0;
377 *flock_count = 0;
378
379 ctx = locks_inode_context(inode);
380 if (ctx) {
381 spin_lock(&ctx->flc_lock);
382 list_for_each_entry(lock, &ctx->flc_posix, fl_list)
383 ++(*fcntl_count);
384 list_for_each_entry(lock, &ctx->flc_flock, fl_list)
385 ++(*flock_count);
386 spin_unlock(&ctx->flc_lock);
387 }
388 dout("counted %d flock locks and %d fcntl locks\n",
389 *flock_count, *fcntl_count);
390}
391
392/*
393 * Given a pointer to a lock, convert it to a ceph filelock
394 */
395static int lock_to_ceph_filelock(struct file_lock *lock,
396 struct ceph_filelock *cephlock)
397{
398 int err = 0;
399 cephlock->start = cpu_to_le64(lock->fl_start);
400 cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
401 cephlock->client = cpu_to_le64(0);
402 cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
403 cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
404
405 switch (lock->fl_type) {
406 case F_RDLCK:
407 cephlock->type = CEPH_LOCK_SHARED;
408 break;
409 case F_WRLCK:
410 cephlock->type = CEPH_LOCK_EXCL;
411 break;
412 case F_UNLCK:
413 cephlock->type = CEPH_LOCK_UNLOCK;
414 break;
415 default:
416 dout("Have unknown lock type %d\n", lock->fl_type);
417 err = -EINVAL;
418 }
419
420 return err;
421}
422
423/*
424 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
425 * array. Must be called with inode->i_lock already held.
426 * If we encounter more of a specific lock type than expected, return -ENOSPC.
427 */
428int ceph_encode_locks_to_buffer(struct inode *inode,
429 struct ceph_filelock *flocks,
430 int num_fcntl_locks, int num_flock_locks)
431{
432 struct file_lock *lock;
433 struct file_lock_context *ctx = locks_inode_context(inode);
434 int err = 0;
435 int seen_fcntl = 0;
436 int seen_flock = 0;
437 int l = 0;
438
439 dout("encoding %d flock and %d fcntl locks\n", num_flock_locks,
440 num_fcntl_locks);
441
442 if (!ctx)
443 return 0;
444
445 spin_lock(&ctx->flc_lock);
446 list_for_each_entry(lock, &ctx->flc_posix, fl_list) {
447 ++seen_fcntl;
448 if (seen_fcntl > num_fcntl_locks) {
449 err = -ENOSPC;
450 goto fail;
451 }
452 err = lock_to_ceph_filelock(lock, &flocks[l]);
453 if (err)
454 goto fail;
455 ++l;
456 }
457 list_for_each_entry(lock, &ctx->flc_flock, fl_list) {
458 ++seen_flock;
459 if (seen_flock > num_flock_locks) {
460 err = -ENOSPC;
461 goto fail;
462 }
463 err = lock_to_ceph_filelock(lock, &flocks[l]);
464 if (err)
465 goto fail;
466 ++l;
467 }
468fail:
469 spin_unlock(&ctx->flc_lock);
470 return err;
471}
472
473/*
474 * Copy the encoded flock and fcntl locks into the pagelist.
475 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
476 * sequential flock locks.
477 * Returns zero on success.
478 */
479int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
480 struct ceph_pagelist *pagelist,
481 int num_fcntl_locks, int num_flock_locks)
482{
483 int err = 0;
484 __le32 nlocks;
485
486 nlocks = cpu_to_le32(num_fcntl_locks);
487 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
488 if (err)
489 goto out_fail;
490
491 if (num_fcntl_locks > 0) {
492 err = ceph_pagelist_append(pagelist, flocks,
493 num_fcntl_locks * sizeof(*flocks));
494 if (err)
495 goto out_fail;
496 }
497
498 nlocks = cpu_to_le32(num_flock_locks);
499 err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
500 if (err)
501 goto out_fail;
502
503 if (num_flock_locks > 0) {
504 err = ceph_pagelist_append(pagelist, &flocks[num_fcntl_locks],
505 num_flock_locks * sizeof(*flocks));
506 }
507out_fail:
508 return err;
509}