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