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v3.15
 
  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;
 
 
 12
 13static inline u64 secure_addr(void *addr)
 14{
 15	u64 v = lock_secret ^ (u64)(unsigned long)addr;
 16	/*
 17	 * Set the most significant bit, so that MDS knows the 'owner'
 18	 * is sufficient to identify the owner of lock. (old code uses
 19	 * both 'owner' and 'pid')
 20	 */
 21	v |= (1ULL << 63);
 22	return v;
 23}
 24
 25void __init ceph_flock_init(void)
 26{
 27	get_random_bytes(&lock_secret, sizeof(lock_secret));
 28}
 29
 30/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31 * Implement fcntl and flock locking functions.
 32 */
 33static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
 34			     int cmd, u8 wait, struct file_lock *fl)
 35{
 36	struct inode *inode = file_inode(file);
 37	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 38	struct ceph_mds_request *req;
 39	int err;
 40	u64 length = 0;
 41	u64 owner;
 42
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 43	req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
 44	if (IS_ERR(req))
 45		return PTR_ERR(req);
 46	req->r_inode = inode;
 47	ihold(inode);
 48	req->r_num_caps = 1;
 49
 50	/* mds requires start and length rather than start and end */
 51	if (LLONG_MAX == fl->fl_end)
 52		length = 0;
 53	else
 54		length = fl->fl_end - fl->fl_start + 1;
 55
 56	if (lock_type == CEPH_LOCK_FCNTL)
 57		owner = secure_addr(fl->fl_owner);
 58	else
 59		owner = secure_addr(fl->fl_file);
 60
 61	dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
 62	     "start: %llu, length: %llu, wait: %d, type: %d", (int)lock_type,
 63	     (int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
 64	     wait, fl->fl_type);
 65
 66	req->r_args.filelock_change.rule = lock_type;
 67	req->r_args.filelock_change.type = cmd;
 68	req->r_args.filelock_change.owner = cpu_to_le64(owner);
 69	req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
 70	req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
 71	req->r_args.filelock_change.length = cpu_to_le64(length);
 72	req->r_args.filelock_change.wait = wait;
 73
 74	err = ceph_mdsc_do_request(mdsc, inode, req);
 75
 76	if (operation == CEPH_MDS_OP_GETFILELOCK) {
 77		fl->fl_pid = le64_to_cpu(req->r_reply_info.filelock_reply->pid);
 
 
 78		if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
 79			fl->fl_type = F_RDLCK;
 80		else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
 81			fl->fl_type = F_WRLCK;
 82		else
 83			fl->fl_type = F_UNLCK;
 84
 85		fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
 86		length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
 87						 le64_to_cpu(req->r_reply_info.filelock_reply->length);
 88		if (length >= 1)
 89			fl->fl_end = length -1;
 90		else
 91			fl->fl_end = 0;
 92
 93	}
 94	ceph_mdsc_put_request(req);
 95	dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
 96	     "length: %llu, wait: %d, type: %d, err code %d", (int)lock_type,
 97	     (int)operation, (u64)fl->fl_pid, fl->fl_start,
 98	     length, wait, fl->fl_type, err);
 99	return err;
100}
101
102/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
103 * Attempt to set an fcntl lock.
104 * For now, this just goes away to the server. Later it may be more awesome.
105 */
106int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
107{
108	u8 lock_cmd;
109	int err;
110	u8 wait = 0;
111	u16 op = CEPH_MDS_OP_SETFILELOCK;
 
 
112
113	if (!(fl->fl_flags & FL_POSIX))
114		return -ENOLCK;
115	/* No mandatory locks */
116	if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
117		return -ENOLCK;
118
119	dout("ceph_lock, fl_owner: %p", fl->fl_owner);
 
 
 
120
121	/* set wait bit as appropriate, then make command as Ceph expects it*/
122	if (IS_GETLK(cmd))
123		op = CEPH_MDS_OP_GETFILELOCK;
124	else if (IS_SETLKW(cmd))
125		wait = 1;
126
 
 
 
 
 
 
 
 
 
 
 
127	if (F_RDLCK == fl->fl_type)
128		lock_cmd = CEPH_LOCK_SHARED;
129	else if (F_WRLCK == fl->fl_type)
130		lock_cmd = CEPH_LOCK_EXCL;
131	else
132		lock_cmd = CEPH_LOCK_UNLOCK;
133
134	err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file, lock_cmd, wait, fl);
 
 
 
 
 
 
135	if (!err) {
136		if (op != CEPH_MDS_OP_GETFILELOCK) {
137			dout("mds locked, locking locally");
138			err = posix_lock_file(file, fl, NULL);
139			if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
140				/* undo! This should only happen if
141				 * the kernel detects local
142				 * deadlock. */
143				ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
144						  CEPH_LOCK_UNLOCK, 0, fl);
145				dout("got %d on posix_lock_file, undid lock",
146				     err);
147			}
148		}
149
150	} else if (err == -ERESTARTSYS) {
151		dout("undoing lock\n");
152		ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
153				  CEPH_LOCK_UNLOCK, 0, fl);
154	}
155	return err;
156}
157
158int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
159{
160	u8 lock_cmd;
161	int err;
 
162	u8 wait = 0;
 
163
164	if (!(fl->fl_flags & FL_FLOCK))
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_flock, fl_file: %p", fl->fl_file);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
171
172	if (IS_SETLKW(cmd))
173		wait = 1;
174
175	if (F_RDLCK == fl->fl_type)
176		lock_cmd = CEPH_LOCK_SHARED;
177	else if (F_WRLCK == fl->fl_type)
178		lock_cmd = CEPH_LOCK_EXCL;
179	else
180		lock_cmd = CEPH_LOCK_UNLOCK;
181
 
 
 
 
 
 
182	err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
183				file, lock_cmd, wait, fl);
184	if (!err) {
185		err = flock_lock_file_wait(file, fl);
186		if (err) {
187			ceph_lock_message(CEPH_LOCK_FLOCK,
188					  CEPH_MDS_OP_SETFILELOCK,
189					  file, CEPH_LOCK_UNLOCK, 0, fl);
190			dout("got %d on flock_lock_file_wait, undid lock", err);
191		}
192	} else if (err == -ERESTARTSYS) {
193		dout("undoing lock\n");
194		ceph_lock_message(CEPH_LOCK_FLOCK,
195				  CEPH_MDS_OP_SETFILELOCK,
196				  file, CEPH_LOCK_UNLOCK, 0, fl);
197	}
198	return err;
199}
200
201/**
202 * Must be called with lock_flocks() already held. Fills in the passed
203 * counter variables, so you can prepare pagelist metadata before calling
204 * ceph_encode_locks.
205 */
206void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
207{
208	struct file_lock *lock;
 
209
210	*fcntl_count = 0;
211	*flock_count = 0;
212
213	for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
214		if (lock->fl_flags & FL_POSIX)
 
 
215			++(*fcntl_count);
216		else if (lock->fl_flags & FL_FLOCK)
217			++(*flock_count);
 
218	}
219	dout("counted %d flock locks and %d fcntl locks",
220	     *flock_count, *fcntl_count);
221}
222
223/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
224 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
225 * array. Must be called with inode->i_lock already held.
226 * If we encounter more of a specific lock type than expected, return -ENOSPC.
227 */
228int ceph_encode_locks_to_buffer(struct inode *inode,
229				struct ceph_filelock *flocks,
230				int num_fcntl_locks, int num_flock_locks)
231{
232	struct file_lock *lock;
 
233	int err = 0;
234	int seen_fcntl = 0;
235	int seen_flock = 0;
236	int l = 0;
237
238	dout("encoding %d flock and %d fcntl locks", num_flock_locks,
239	     num_fcntl_locks);
240
241	for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
242		if (lock->fl_flags & FL_POSIX) {
243			++seen_fcntl;
244			if (seen_fcntl > num_fcntl_locks) {
245				err = -ENOSPC;
246				goto fail;
247			}
248			err = lock_to_ceph_filelock(lock, &flocks[l]);
249			if (err)
250				goto fail;
251			++l;
252		}
 
 
 
 
253	}
254	for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
255		if (lock->fl_flags & FL_FLOCK) {
256			++seen_flock;
257			if (seen_flock > num_flock_locks) {
258				err = -ENOSPC;
259				goto fail;
260			}
261			err = lock_to_ceph_filelock(lock, &flocks[l]);
262			if (err)
263				goto fail;
264			++l;
265		}
 
 
 
 
266	}
267fail:
 
268	return err;
269}
270
271/**
272 * Copy the encoded flock and fcntl locks into the pagelist.
273 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
274 * sequential flock locks.
275 * Returns zero on success.
276 */
277int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
278			   struct ceph_pagelist *pagelist,
279			   int num_fcntl_locks, int num_flock_locks)
280{
281	int err = 0;
282	__le32 nlocks;
283
284	nlocks = cpu_to_le32(num_fcntl_locks);
285	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
286	if (err)
287		goto out_fail;
288
289	err = ceph_pagelist_append(pagelist, flocks,
290				   num_fcntl_locks * sizeof(*flocks));
291	if (err)
292		goto out_fail;
 
 
293
294	nlocks = cpu_to_le32(num_flock_locks);
295	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
296	if (err)
297		goto out_fail;
298
299	err = ceph_pagelist_append(pagelist,
300				   &flocks[num_fcntl_locks],
301				   num_flock_locks * sizeof(*flocks));
302out_fail:
303	return err;
304}
305
306/*
307 * Given a pointer to a lock, convert it to a ceph filelock
308 */
309int lock_to_ceph_filelock(struct file_lock *lock,
310			  struct ceph_filelock *cephlock)
311{
312	int err = 0;
313	cephlock->start = cpu_to_le64(lock->fl_start);
314	cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
315	cephlock->client = cpu_to_le64(0);
316	cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
317	if (lock->fl_flags & FL_POSIX)
318		cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
319	else
320		cephlock->owner = cpu_to_le64(secure_addr(lock->fl_file));
321
322	switch (lock->fl_type) {
323	case F_RDLCK:
324		cephlock->type = CEPH_LOCK_SHARED;
325		break;
326	case F_WRLCK:
327		cephlock->type = CEPH_LOCK_EXCL;
328		break;
329	case F_UNLCK:
330		cephlock->type = CEPH_LOCK_UNLOCK;
331		break;
332	default:
333		dout("Have unknown lock type %d", lock->fl_type);
334		err = -EINVAL;
335	}
336
337	return err;
338}
v6.2
  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}