Linux Audio

Check our new training course

Linux debugging, profiling, tracing and performance analysis training

Apr 14-17, 2025
Register
Loading...
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}
v6.8
  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/filelock.h>
 11#include <linux/ceph/pagelist.h>
 12
 13static u64 lock_secret;
 14static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
 15                                         struct ceph_mds_request *req);
 16
 17static inline u64 secure_addr(void *addr)
 18{
 19	u64 v = lock_secret ^ (u64)(unsigned long)addr;
 20	/*
 21	 * Set the most significant bit, so that MDS knows the 'owner'
 22	 * is sufficient to identify the owner of lock. (old code uses
 23	 * both 'owner' and 'pid')
 24	 */
 25	v |= (1ULL << 63);
 26	return v;
 27}
 28
 29void __init ceph_flock_init(void)
 30{
 31	get_random_bytes(&lock_secret, sizeof(lock_secret));
 32}
 33
 34static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 35{
 36	struct inode *inode = file_inode(dst->fl_file);
 37	atomic_inc(&ceph_inode(inode)->i_filelock_ref);
 38	dst->fl_u.ceph.inode = igrab(inode);
 39}
 40
 41/*
 42 * Do not use the 'fl->fl_file' in release function, which
 43 * is possibly already released by another thread.
 44 */
 45static void ceph_fl_release_lock(struct file_lock *fl)
 46{
 47	struct inode *inode = fl->fl_u.ceph.inode;
 48	struct ceph_inode_info *ci;
 49
 50	/*
 51	 * If inode is NULL it should be a request file_lock,
 52	 * nothing we can do.
 53	 */
 54	if (!inode)
 55		return;
 56
 57	ci = ceph_inode(inode);
 58	if (atomic_dec_and_test(&ci->i_filelock_ref)) {
 59		/* clear error when all locks are released */
 60		spin_lock(&ci->i_ceph_lock);
 61		ci->i_ceph_flags &= ~CEPH_I_ERROR_FILELOCK;
 62		spin_unlock(&ci->i_ceph_lock);
 63	}
 64	fl->fl_u.ceph.inode = NULL;
 65	iput(inode);
 66}
 67
 68static const struct file_lock_operations ceph_fl_lock_ops = {
 69	.fl_copy_lock = ceph_fl_copy_lock,
 70	.fl_release_private = ceph_fl_release_lock,
 71};
 72
 73/*
 74 * Implement fcntl and flock locking functions.
 75 */
 76static int ceph_lock_message(u8 lock_type, u16 operation, struct inode *inode,
 77			     int cmd, u8 wait, struct file_lock *fl)
 78{
 79	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
 80	struct ceph_client *cl = mdsc->fsc->client;
 81	struct ceph_mds_request *req;
 82	int err;
 83	u64 length = 0;
 84	u64 owner;
 85
 86	if (operation == CEPH_MDS_OP_SETFILELOCK) {
 87		/*
 88		 * increasing i_filelock_ref closes race window between
 89		 * handling request reply and adding file_lock struct to
 90		 * inode. Otherwise, auth caps may get trimmed in the
 91		 * window. Caller function will decrease the counter.
 92		 */
 93		fl->fl_ops = &ceph_fl_lock_ops;
 94		fl->fl_ops->fl_copy_lock(fl, NULL);
 95	}
 96
 97	if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK)
 98		wait = 0;
 99
100	req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
101	if (IS_ERR(req))
102		return PTR_ERR(req);
103	req->r_inode = inode;
104	ihold(inode);
105	req->r_num_caps = 1;
106
107	/* mds requires start and length rather than start and end */
108	if (LLONG_MAX == fl->fl_end)
109		length = 0;
110	else
111		length = fl->fl_end - fl->fl_start + 1;
112
113	owner = secure_addr(fl->fl_owner);
 
 
 
114
115	doutc(cl, "rule: %d, op: %d, owner: %llx, pid: %llu, "
116		    "start: %llu, length: %llu, wait: %d, type: %d\n",
117		    (int)lock_type, (int)operation, owner, (u64)fl->fl_pid,
118		    fl->fl_start, length, wait, fl->fl_type);
119
120	req->r_args.filelock_change.rule = lock_type;
121	req->r_args.filelock_change.type = cmd;
122	req->r_args.filelock_change.owner = cpu_to_le64(owner);
123	req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
124	req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
125	req->r_args.filelock_change.length = cpu_to_le64(length);
126	req->r_args.filelock_change.wait = wait;
127
128	err = ceph_mdsc_submit_request(mdsc, inode, req);
129	if (!err)
130		err = ceph_mdsc_wait_request(mdsc, req, wait ?
131					ceph_lock_wait_for_completion : NULL);
132	if (!err && operation == CEPH_MDS_OP_GETFILELOCK) {
133		fl->fl_pid = -le64_to_cpu(req->r_reply_info.filelock_reply->pid);
134		if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
135			fl->fl_type = F_RDLCK;
136		else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
137			fl->fl_type = F_WRLCK;
138		else
139			fl->fl_type = F_UNLCK;
140
141		fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
142		length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
143						 le64_to_cpu(req->r_reply_info.filelock_reply->length);
144		if (length >= 1)
145			fl->fl_end = length -1;
146		else
147			fl->fl_end = 0;
148
149	}
150	ceph_mdsc_put_request(req);
151	doutc(cl, "rule: %d, op: %d, pid: %llu, start: %llu, "
152	      "length: %llu, wait: %d, type: %d, err code %d\n",
153	      (int)lock_type, (int)operation, (u64)fl->fl_pid,
154	      fl->fl_start, length, wait, fl->fl_type, err);
155	return err;
156}
157
158static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
159                                         struct ceph_mds_request *req)
160{
161	struct ceph_client *cl = mdsc->fsc->client;
162	struct ceph_mds_request *intr_req;
163	struct inode *inode = req->r_inode;
164	int err, lock_type;
165
166	BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
167	if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
168		lock_type = CEPH_LOCK_FCNTL_INTR;
169	else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
170		lock_type = CEPH_LOCK_FLOCK_INTR;
171	else
172		BUG_ON(1);
173	BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);
174
175	err = wait_for_completion_interruptible(&req->r_completion);
176	if (!err)
177		return 0;
178
179	doutc(cl, "request %llu was interrupted\n", req->r_tid);
180
181	mutex_lock(&mdsc->mutex);
182	if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
183		err = 0;
184	} else {
185		/*
186		 * ensure we aren't running concurrently with
187		 * ceph_fill_trace or ceph_readdir_prepopulate, which
188		 * rely on locks (dir mutex) held by our caller.
189		 */
190		mutex_lock(&req->r_fill_mutex);
191		req->r_err = err;
192		set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
193		mutex_unlock(&req->r_fill_mutex);
194
195		if (!req->r_session) {
196			// haven't sent the request
197			err = 0;
198		}
199	}
200	mutex_unlock(&mdsc->mutex);
201	if (!err)
202		return 0;
203
204	intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
205					    USE_AUTH_MDS);
206	if (IS_ERR(intr_req))
207		return PTR_ERR(intr_req);
208
209	intr_req->r_inode = inode;
210	ihold(inode);
211	intr_req->r_num_caps = 1;
212
213	intr_req->r_args.filelock_change = req->r_args.filelock_change;
214	intr_req->r_args.filelock_change.rule = lock_type;
215	intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;
216
217	err = ceph_mdsc_do_request(mdsc, inode, intr_req);
218	ceph_mdsc_put_request(intr_req);
219
220	if (err && err != -ERESTARTSYS)
221		return err;
222
223	wait_for_completion_killable(&req->r_safe_completion);
224	return 0;
225}
226
227static int try_unlock_file(struct file *file, struct file_lock *fl)
228{
229	int err;
230	unsigned int orig_flags = fl->fl_flags;
231	fl->fl_flags |= FL_EXISTS;
232	err = locks_lock_file_wait(file, fl);
233	fl->fl_flags = orig_flags;
234	if (err == -ENOENT) {
235		if (!(orig_flags & FL_EXISTS))
236			err = 0;
237		return err;
238	}
239	return 1;
240}
241
242/*
243 * Attempt to set an fcntl lock.
244 * For now, this just goes away to the server. Later it may be more awesome.
245 */
246int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
247{
248	struct inode *inode = file_inode(file);
249	struct ceph_inode_info *ci = ceph_inode(inode);
250	struct ceph_client *cl = ceph_inode_to_client(inode);
251	int err = 0;
252	u16 op = CEPH_MDS_OP_SETFILELOCK;
253	u8 wait = 0;
254	u8 lock_cmd;
255
256	if (!(fl->fl_flags & FL_POSIX))
257		return -ENOLCK;
 
 
 
258
259	if (ceph_inode_is_shutdown(inode))
260		return -ESTALE;
261
262	doutc(cl, "fl_owner: %p\n", fl->fl_owner);
263
264	/* set wait bit as appropriate, then make command as Ceph expects it*/
265	if (IS_GETLK(cmd))
266		op = CEPH_MDS_OP_GETFILELOCK;
267	else if (IS_SETLKW(cmd))
268		wait = 1;
269
270	spin_lock(&ci->i_ceph_lock);
271	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
272		err = -EIO;
273	}
274	spin_unlock(&ci->i_ceph_lock);
275	if (err < 0) {
276		if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type)
277			posix_lock_file(file, fl, NULL);
278		return err;
279	}
280
281	if (F_RDLCK == fl->fl_type)
282		lock_cmd = CEPH_LOCK_SHARED;
283	else if (F_WRLCK == fl->fl_type)
284		lock_cmd = CEPH_LOCK_EXCL;
285	else
286		lock_cmd = CEPH_LOCK_UNLOCK;
287
288	if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type) {
289		err = try_unlock_file(file, fl);
290		if (err <= 0)
291			return err;
292	}
293
294	err = ceph_lock_message(CEPH_LOCK_FCNTL, op, inode, lock_cmd, wait, fl);
295	if (!err) {
296		if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK != fl->fl_type) {
297			doutc(cl, "locking locally\n");
298			err = posix_lock_file(file, fl, NULL);
299			if (err) {
300				/* undo! This should only happen if
301				 * the kernel detects local
302				 * deadlock. */
303				ceph_lock_message(CEPH_LOCK_FCNTL, op, inode,
304						  CEPH_LOCK_UNLOCK, 0, fl);
305				doutc(cl, "got %d on posix_lock_file, undid lock\n",
306				      err);
307			}
308		}
 
 
 
 
 
309	}
310	return err;
311}
312
313int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
314{
315	struct inode *inode = file_inode(file);
316	struct ceph_inode_info *ci = ceph_inode(inode);
317	struct ceph_client *cl = ceph_inode_to_client(inode);
318	int err = 0;
319	u8 wait = 0;
320	u8 lock_cmd;
321
322	if (!(fl->fl_flags & FL_FLOCK))
323		return -ENOLCK;
 
 
 
324
325	if (ceph_inode_is_shutdown(inode))
326		return -ESTALE;
327
328	doutc(cl, "fl_file: %p\n", fl->fl_file);
329
330	spin_lock(&ci->i_ceph_lock);
331	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
332		err = -EIO;
333	}
334	spin_unlock(&ci->i_ceph_lock);
335	if (err < 0) {
336		if (F_UNLCK == fl->fl_type)
337			locks_lock_file_wait(file, fl);
338		return err;
339	}
340
341	if (IS_SETLKW(cmd))
342		wait = 1;
343
344	if (F_RDLCK == fl->fl_type)
345		lock_cmd = CEPH_LOCK_SHARED;
346	else if (F_WRLCK == fl->fl_type)
347		lock_cmd = CEPH_LOCK_EXCL;
348	else
349		lock_cmd = CEPH_LOCK_UNLOCK;
350
351	if (F_UNLCK == fl->fl_type) {
352		err = try_unlock_file(file, fl);
353		if (err <= 0)
354			return err;
355	}
356
357	err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
358				inode, lock_cmd, wait, fl);
359	if (!err && F_UNLCK != fl->fl_type) {
360		err = locks_lock_file_wait(file, fl);
361		if (err) {
362			ceph_lock_message(CEPH_LOCK_FLOCK,
363					  CEPH_MDS_OP_SETFILELOCK,
364					  inode, CEPH_LOCK_UNLOCK, 0, fl);
365			doutc(cl, "got %d on locks_lock_file_wait, undid lock\n",
366			      err);
367		}
 
 
 
 
 
368	}
369	return err;
370}
371
372/*
373 * Fills in the passed counter variables, so you can prepare pagelist metadata
374 * before calling ceph_encode_locks.
 
375 */
376void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
377{
378	struct ceph_client *cl = ceph_inode_to_client(inode);
379	struct file_lock *lock;
380	struct file_lock_context *ctx;
381
382	*fcntl_count = 0;
383	*flock_count = 0;
384
385	ctx = locks_inode_context(inode);
386	if (ctx) {
387		spin_lock(&ctx->flc_lock);
388		list_for_each_entry(lock, &ctx->flc_posix, fl_list)
389			++(*fcntl_count);
390		list_for_each_entry(lock, &ctx->flc_flock, fl_list)
391			++(*flock_count);
392		spin_unlock(&ctx->flc_lock);
393	}
394	doutc(cl, "counted %d flock locks and %d fcntl locks\n",
395	      *flock_count, *fcntl_count);
396}
397
398/*
399 * Given a pointer to a lock, convert it to a ceph filelock
400 */
401static int lock_to_ceph_filelock(struct inode *inode,
402				 struct file_lock *lock,
403				 struct ceph_filelock *cephlock)
404{
405	struct ceph_client *cl = ceph_inode_to_client(inode);
406	int err = 0;
407
408	cephlock->start = cpu_to_le64(lock->fl_start);
409	cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
410	cephlock->client = cpu_to_le64(0);
411	cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
412	cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
413
414	switch (lock->fl_type) {
415	case F_RDLCK:
416		cephlock->type = CEPH_LOCK_SHARED;
417		break;
418	case F_WRLCK:
419		cephlock->type = CEPH_LOCK_EXCL;
420		break;
421	case F_UNLCK:
422		cephlock->type = CEPH_LOCK_UNLOCK;
423		break;
424	default:
425		doutc(cl, "Have unknown lock type %d\n", lock->fl_type);
426		err = -EINVAL;
427	}
428
429	return err;
430}
431
432/*
433 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
434 * array. Must be called with inode->i_lock already held.
435 * If we encounter more of a specific lock type than expected, return -ENOSPC.
436 */
437int ceph_encode_locks_to_buffer(struct inode *inode,
438				struct ceph_filelock *flocks,
439				int num_fcntl_locks, int num_flock_locks)
440{
441	struct file_lock *lock;
442	struct file_lock_context *ctx = locks_inode_context(inode);
443	struct ceph_client *cl = ceph_inode_to_client(inode);
444	int err = 0;
445	int seen_fcntl = 0;
446	int seen_flock = 0;
447	int l = 0;
448
449	doutc(cl, "encoding %d flock and %d fcntl locks\n", num_flock_locks,
450	      num_fcntl_locks);
451
452	if (!ctx)
453		return 0;
454
455	spin_lock(&ctx->flc_lock);
456	list_for_each_entry(lock, &ctx->flc_posix, fl_list) {
457		++seen_fcntl;
458		if (seen_fcntl > num_fcntl_locks) {
459			err = -ENOSPC;
460			goto fail;
 
 
461		}
462		err = lock_to_ceph_filelock(inode, lock, &flocks[l]);
463		if (err)
464			goto fail;
465		++l;
466	}
467	list_for_each_entry(lock, &ctx->flc_flock, fl_list) {
468		++seen_flock;
469		if (seen_flock > num_flock_locks) {
470			err = -ENOSPC;
471			goto fail;
 
 
 
 
 
 
472		}
473		err = lock_to_ceph_filelock(inode, lock, &flocks[l]);
474		if (err)
475			goto fail;
476		++l;
477	}
478fail:
479	spin_unlock(&ctx->flc_lock);
480	return err;
481}
482
483/*
484 * Copy the encoded flock and fcntl locks into the pagelist.
485 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
486 * sequential flock locks.
487 * Returns zero on success.
488 */
489int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
490			   struct ceph_pagelist *pagelist,
491			   int num_fcntl_locks, int num_flock_locks)
492{
493	int err = 0;
494	__le32 nlocks;
495
496	nlocks = cpu_to_le32(num_fcntl_locks);
497	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
498	if (err)
499		goto out_fail;
500
501	if (num_fcntl_locks > 0) {
502		err = ceph_pagelist_append(pagelist, flocks,
503					   num_fcntl_locks * sizeof(*flocks));
504		if (err)
505			goto out_fail;
506	}
507
508	nlocks = cpu_to_le32(num_flock_locks);
509	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
510	if (err)
511		goto out_fail;
512
513	if (num_flock_locks > 0) {
514		err = ceph_pagelist_append(pagelist, &flocks[num_fcntl_locks],
515					   num_flock_locks * sizeof(*flocks));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
516	}
517out_fail:
518	return err;
519}