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