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1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/file.h>
4#include <linux/namei.h>
5
6#include "super.h"
7#include "mds_client.h"
8#include <linux/ceph/pagelist.h>
9
10/**
11 * Implement fcntl and flock locking functions.
12 */
13static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
14 int cmd, u8 wait, struct file_lock *fl)
15{
16 struct inode *inode = file->f_dentry->d_inode;
17 struct ceph_mds_client *mdsc =
18 ceph_sb_to_client(inode->i_sb)->mdsc;
19 struct ceph_mds_request *req;
20 int err;
21 u64 length = 0;
22
23 req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
24 if (IS_ERR(req))
25 return PTR_ERR(req);
26 req->r_inode = inode;
27 ihold(inode);
28
29 /* mds requires start and length rather than start and end */
30 if (LLONG_MAX == fl->fl_end)
31 length = 0;
32 else
33 length = fl->fl_end - fl->fl_start + 1;
34
35 dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
36 "length: %llu, wait: %d, type: %d", (int)lock_type,
37 (int)operation, (u64)fl->fl_pid, fl->fl_start,
38 length, wait, fl->fl_type);
39
40 req->r_args.filelock_change.rule = lock_type;
41 req->r_args.filelock_change.type = cmd;
42 req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
43 /* This should be adjusted, but I'm not sure if
44 namespaces actually get id numbers*/
45 req->r_args.filelock_change.pid_namespace =
46 cpu_to_le64((u64)(unsigned long)fl->fl_nspid);
47 req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
48 req->r_args.filelock_change.length = cpu_to_le64(length);
49 req->r_args.filelock_change.wait = wait;
50
51 err = ceph_mdsc_do_request(mdsc, inode, req);
52
53 if ( operation == CEPH_MDS_OP_GETFILELOCK){
54 fl->fl_pid = le64_to_cpu(req->r_reply_info.filelock_reply->pid);
55 if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
56 fl->fl_type = F_RDLCK;
57 else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
58 fl->fl_type = F_WRLCK;
59 else
60 fl->fl_type = F_UNLCK;
61
62 fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
63 length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
64 le64_to_cpu(req->r_reply_info.filelock_reply->length);
65 if (length >= 1)
66 fl->fl_end = length -1;
67 else
68 fl->fl_end = 0;
69
70 }
71 ceph_mdsc_put_request(req);
72 dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
73 "length: %llu, wait: %d, type: %d, err code %d", (int)lock_type,
74 (int)operation, (u64)fl->fl_pid, fl->fl_start,
75 length, wait, fl->fl_type, err);
76 return err;
77}
78
79/**
80 * Attempt to set an fcntl lock.
81 * For now, this just goes away to the server. Later it may be more awesome.
82 */
83int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
84{
85 u8 lock_cmd;
86 int err;
87 u8 wait = 0;
88 u16 op = CEPH_MDS_OP_SETFILELOCK;
89
90 fl->fl_nspid = get_pid(task_tgid(current));
91 dout("ceph_lock, fl_pid:%d", fl->fl_pid);
92
93 /* set wait bit as appropriate, then make command as Ceph expects it*/
94 if (F_SETLKW == cmd)
95 wait = 1;
96 if (F_GETLK == cmd)
97 op = CEPH_MDS_OP_GETFILELOCK;
98
99 if (F_RDLCK == fl->fl_type)
100 lock_cmd = CEPH_LOCK_SHARED;
101 else if (F_WRLCK == fl->fl_type)
102 lock_cmd = CEPH_LOCK_EXCL;
103 else
104 lock_cmd = CEPH_LOCK_UNLOCK;
105
106 err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file, lock_cmd, wait, fl);
107 if (!err) {
108 if ( op != CEPH_MDS_OP_GETFILELOCK ){
109 dout("mds locked, locking locally");
110 err = posix_lock_file(file, fl, NULL);
111 if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
112 /* undo! This should only happen if
113 * the kernel detects local
114 * deadlock. */
115 ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
116 CEPH_LOCK_UNLOCK, 0, fl);
117 dout("got %d on posix_lock_file, undid lock",
118 err);
119 }
120 }
121
122 } else if (err == -ERESTARTSYS) {
123 dout("undoing lock\n");
124 ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
125 CEPH_LOCK_UNLOCK, 0, fl);
126 }
127 return err;
128}
129
130int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
131{
132 u8 lock_cmd;
133 int err;
134 u8 wait = 1;
135
136 fl->fl_nspid = get_pid(task_tgid(current));
137 dout("ceph_flock, fl_pid:%d", fl->fl_pid);
138
139 /* set wait bit, then clear it out of cmd*/
140 if (cmd & LOCK_NB)
141 wait = 0;
142 cmd = cmd & (LOCK_SH | LOCK_EX | LOCK_UN);
143 /* set command sequence that Ceph wants to see:
144 shared lock, exclusive lock, or unlock */
145 if (LOCK_SH == cmd)
146 lock_cmd = CEPH_LOCK_SHARED;
147 else if (LOCK_EX == cmd)
148 lock_cmd = CEPH_LOCK_EXCL;
149 else
150 lock_cmd = CEPH_LOCK_UNLOCK;
151
152 err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
153 file, lock_cmd, wait, fl);
154 if (!err) {
155 err = flock_lock_file_wait(file, fl);
156 if (err) {
157 ceph_lock_message(CEPH_LOCK_FLOCK,
158 CEPH_MDS_OP_SETFILELOCK,
159 file, CEPH_LOCK_UNLOCK, 0, fl);
160 dout("got %d on flock_lock_file_wait, undid lock", err);
161 }
162 } else if (err == -ERESTARTSYS) {
163 dout("undoing lock\n");
164 ceph_lock_message(CEPH_LOCK_FLOCK,
165 CEPH_MDS_OP_SETFILELOCK,
166 file, CEPH_LOCK_UNLOCK, 0, fl);
167 }
168 return err;
169}
170
171/**
172 * Must be called with BKL already held. Fills in the passed
173 * counter variables, so you can prepare pagelist metadata before calling
174 * ceph_encode_locks.
175 */
176void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
177{
178 struct file_lock *lock;
179
180 *fcntl_count = 0;
181 *flock_count = 0;
182
183 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
184 if (lock->fl_flags & FL_POSIX)
185 ++(*fcntl_count);
186 else if (lock->fl_flags & FL_FLOCK)
187 ++(*flock_count);
188 }
189 dout("counted %d flock locks and %d fcntl locks",
190 *flock_count, *fcntl_count);
191}
192
193/**
194 * Encode the flock and fcntl locks for the given inode into the pagelist.
195 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
196 * sequential flock locks.
197 * Must be called with lock_flocks() already held.
198 * If we encounter more of a specific lock type than expected,
199 * we return the value 1.
200 */
201int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist,
202 int num_fcntl_locks, int num_flock_locks)
203{
204 struct file_lock *lock;
205 struct ceph_filelock cephlock;
206 int err = 0;
207 int seen_fcntl = 0;
208 int seen_flock = 0;
209
210 dout("encoding %d flock and %d fcntl locks", num_flock_locks,
211 num_fcntl_locks);
212 err = ceph_pagelist_append(pagelist, &num_fcntl_locks, sizeof(u32));
213 if (err)
214 goto fail;
215 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
216 if (lock->fl_flags & FL_POSIX) {
217 ++seen_fcntl;
218 if (seen_fcntl > num_fcntl_locks) {
219 err = -ENOSPC;
220 goto fail;
221 }
222 err = lock_to_ceph_filelock(lock, &cephlock);
223 if (err)
224 goto fail;
225 err = ceph_pagelist_append(pagelist, &cephlock,
226 sizeof(struct ceph_filelock));
227 }
228 if (err)
229 goto fail;
230 }
231
232 err = ceph_pagelist_append(pagelist, &num_flock_locks, sizeof(u32));
233 if (err)
234 goto fail;
235 for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
236 if (lock->fl_flags & FL_FLOCK) {
237 ++seen_flock;
238 if (seen_flock > num_flock_locks) {
239 err = -ENOSPC;
240 goto fail;
241 }
242 err = lock_to_ceph_filelock(lock, &cephlock);
243 if (err)
244 goto fail;
245 err = ceph_pagelist_append(pagelist, &cephlock,
246 sizeof(struct ceph_filelock));
247 }
248 if (err)
249 goto fail;
250 }
251fail:
252 return err;
253}
254
255/*
256 * Given a pointer to a lock, convert it to a ceph filelock
257 */
258int lock_to_ceph_filelock(struct file_lock *lock,
259 struct ceph_filelock *cephlock)
260{
261 int err = 0;
262
263 cephlock->start = cpu_to_le64(lock->fl_start);
264 cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
265 cephlock->client = cpu_to_le64(0);
266 cephlock->pid = cpu_to_le64(lock->fl_pid);
267 cephlock->pid_namespace =
268 cpu_to_le64((u64)(unsigned long)lock->fl_nspid);
269
270 switch (lock->fl_type) {
271 case F_RDLCK:
272 cephlock->type = CEPH_LOCK_SHARED;
273 break;
274 case F_WRLCK:
275 cephlock->type = CEPH_LOCK_EXCL;
276 break;
277 case F_UNLCK:
278 cephlock->type = CEPH_LOCK_UNLOCK;
279 break;
280 default:
281 dout("Have unknown lock type %d", lock->fl_type);
282 err = -EINVAL;
283 }
284
285 return err;
286}
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_mdsc(inode->i_sb);
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}