12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
2e8d6c554SDavid Howells /* AFS file locking support
3e8d6c554SDavid Howells *
4e8d6c554SDavid Howells * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5e8d6c554SDavid Howells * Written by David Howells (dhowells@redhat.com)
6e8d6c554SDavid Howells */
7e8d6c554SDavid Howells
8e8d6c554SDavid Howells #include "internal.h"
9e8d6c554SDavid Howells
10e8d6c554SDavid Howells #define AFS_LOCK_GRANTED 0
11e8d6c554SDavid Howells #define AFS_LOCK_PENDING 1
124be5975aSDavid Howells #define AFS_LOCK_YOUR_TRY 2
13e8d6c554SDavid Howells
14f044c884SDavid Howells struct workqueue_struct *afs_lock_manager;
15f044c884SDavid Howells
164be5975aSDavid Howells static void afs_next_locker(struct afs_vnode *vnode, int error);
17e8d6c554SDavid Howells static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl);
18e8d6c554SDavid Howells static void afs_fl_release_private(struct file_lock *fl);
19e8d6c554SDavid Howells
206aed6285SAlexey Dobriyan static const struct file_lock_operations afs_lock_ops = {
21e8d6c554SDavid Howells .fl_copy_lock = afs_fl_copy_lock,
22e8d6c554SDavid Howells .fl_release_private = afs_fl_release_private,
23e8d6c554SDavid Howells };
24e8d6c554SDavid Howells
afs_set_lock_state(struct afs_vnode * vnode,enum afs_lock_state state)254be5975aSDavid Howells static inline void afs_set_lock_state(struct afs_vnode *vnode, enum afs_lock_state state)
264be5975aSDavid Howells {
274be5975aSDavid Howells _debug("STATE %u -> %u", vnode->lock_state, state);
284be5975aSDavid Howells vnode->lock_state = state;
294be5975aSDavid Howells }
304be5975aSDavid Howells
31d4696601SDavid Howells static atomic_t afs_file_lock_debug_id;
32d4696601SDavid Howells
33e8d6c554SDavid Howells /*
34e8d6c554SDavid Howells * if the callback is broken on this vnode, then the lock may now be available
35e8d6c554SDavid Howells */
afs_lock_may_be_available(struct afs_vnode * vnode)36e8d6c554SDavid Howells void afs_lock_may_be_available(struct afs_vnode *vnode)
37e8d6c554SDavid Howells {
383b6492dfSDavid Howells _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
39e8d6c554SDavid Howells
404be5975aSDavid Howells spin_lock(&vnode->lock);
414be5975aSDavid Howells if (vnode->lock_state == AFS_VNODE_LOCK_WAITING_FOR_CB)
424be5975aSDavid Howells afs_next_locker(vnode, 0);
43d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_callback_break, 0);
444be5975aSDavid Howells spin_unlock(&vnode->lock);
45e8d6c554SDavid Howells }
46e8d6c554SDavid Howells
47e8d6c554SDavid Howells /*
48e8d6c554SDavid Howells * the lock will time out in 5 minutes unless we extend it, so schedule
49e8d6c554SDavid Howells * extension in a bit less than that time
50e8d6c554SDavid Howells */
afs_schedule_lock_extension(struct afs_vnode * vnode)51e8d6c554SDavid Howells static void afs_schedule_lock_extension(struct afs_vnode *vnode)
52e8d6c554SDavid Howells {
53a690f60aSDavid Howells ktime_t expires_at, now, duration;
54a690f60aSDavid Howells u64 duration_j;
55a690f60aSDavid Howells
56a690f60aSDavid Howells expires_at = ktime_add_ms(vnode->locked_at, AFS_LOCKWAIT * 1000 / 2);
57a690f60aSDavid Howells now = ktime_get_real();
58a690f60aSDavid Howells duration = ktime_sub(expires_at, now);
59a690f60aSDavid Howells if (duration <= 0)
60a690f60aSDavid Howells duration_j = 0;
61a690f60aSDavid Howells else
62a690f60aSDavid Howells duration_j = nsecs_to_jiffies(ktime_to_ns(duration));
63a690f60aSDavid Howells
64a690f60aSDavid Howells queue_delayed_work(afs_lock_manager, &vnode->lock_work, duration_j);
65a690f60aSDavid Howells }
66a690f60aSDavid Howells
67a690f60aSDavid Howells /*
68a690f60aSDavid Howells * In the case of successful completion of a lock operation, record the time
69a690f60aSDavid Howells * the reply appeared and start the lock extension timer.
70a690f60aSDavid Howells */
afs_lock_op_done(struct afs_call * call)71a690f60aSDavid Howells void afs_lock_op_done(struct afs_call *call)
72a690f60aSDavid Howells {
73e49c7b2fSDavid Howells struct afs_operation *op = call->op;
745749ce92SDavid Howells struct afs_vnode *vnode = op->file[0].vnode;
75a690f60aSDavid Howells
76a690f60aSDavid Howells if (call->error == 0) {
77a690f60aSDavid Howells spin_lock(&vnode->lock);
78d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_timestamp, 0);
797903192cSDavid Howells vnode->locked_at = call->issue_time;
80a690f60aSDavid Howells afs_schedule_lock_extension(vnode);
81a690f60aSDavid Howells spin_unlock(&vnode->lock);
82a690f60aSDavid Howells }
83e8d6c554SDavid Howells }
84e8d6c554SDavid Howells
85e8d6c554SDavid Howells /*
86ff8e210aSDavid Howells * grant one or more locks (readlocks are allowed to jump the queue if the
87ff8e210aSDavid Howells * first lock in the queue is itself a readlock)
88ff8e210aSDavid Howells * - the caller must hold the vnode lock
89ff8e210aSDavid Howells */
afs_grant_locks(struct afs_vnode * vnode)904be5975aSDavid Howells static void afs_grant_locks(struct afs_vnode *vnode)
91ff8e210aSDavid Howells {
92ff8e210aSDavid Howells struct file_lock *p, *_p;
934be5975aSDavid Howells bool exclusive = (vnode->lock_type == AFS_LOCK_WRITE);
94ff8e210aSDavid Howells
954be5975aSDavid Howells list_for_each_entry_safe(p, _p, &vnode->pending_locks, fl_u.afs.link) {
964be5975aSDavid Howells if (!exclusive && p->fl_type == F_WRLCK)
974be5975aSDavid Howells continue;
984be5975aSDavid Howells
994be5975aSDavid Howells list_move_tail(&p->fl_u.afs.link, &vnode->granted_locks);
100ff8e210aSDavid Howells p->fl_u.afs.state = AFS_LOCK_GRANTED;
101d4696601SDavid Howells trace_afs_flock_op(vnode, p, afs_flock_op_grant);
102ff8e210aSDavid Howells wake_up(&p->fl_wait);
103ff8e210aSDavid Howells }
104ff8e210aSDavid Howells }
1054be5975aSDavid Howells
1064be5975aSDavid Howells /*
1074be5975aSDavid Howells * If an error is specified, reject every pending lock that matches the
1084be5975aSDavid Howells * authentication and type of the lock we failed to get. If there are any
1094be5975aSDavid Howells * remaining lockers, try to wake up one of them to have a go.
1104be5975aSDavid Howells */
afs_next_locker(struct afs_vnode * vnode,int error)1114be5975aSDavid Howells static void afs_next_locker(struct afs_vnode *vnode, int error)
1124be5975aSDavid Howells {
1134be5975aSDavid Howells struct file_lock *p, *_p, *next = NULL;
1144be5975aSDavid Howells struct key *key = vnode->lock_key;
1154be5975aSDavid Howells unsigned int fl_type = F_RDLCK;
1164be5975aSDavid Howells
1174be5975aSDavid Howells _enter("");
1184be5975aSDavid Howells
1194be5975aSDavid Howells if (vnode->lock_type == AFS_LOCK_WRITE)
1204be5975aSDavid Howells fl_type = F_WRLCK;
1214be5975aSDavid Howells
1224be5975aSDavid Howells list_for_each_entry_safe(p, _p, &vnode->pending_locks, fl_u.afs.link) {
1234be5975aSDavid Howells if (error &&
1244be5975aSDavid Howells p->fl_type == fl_type &&
1254be5975aSDavid Howells afs_file_key(p->fl_file) == key) {
1264be5975aSDavid Howells list_del_init(&p->fl_u.afs.link);
1274be5975aSDavid Howells p->fl_u.afs.state = error;
1284be5975aSDavid Howells wake_up(&p->fl_wait);
129ff8e210aSDavid Howells }
1304be5975aSDavid Howells
1314be5975aSDavid Howells /* Select the next locker to hand off to. */
1324be5975aSDavid Howells if (next &&
1334be5975aSDavid Howells (next->fl_type == F_WRLCK || p->fl_type == F_RDLCK))
1344be5975aSDavid Howells continue;
1354be5975aSDavid Howells next = p;
1364be5975aSDavid Howells }
1374be5975aSDavid Howells
1384be5975aSDavid Howells vnode->lock_key = NULL;
1394be5975aSDavid Howells key_put(key);
1404be5975aSDavid Howells
1414be5975aSDavid Howells if (next) {
1424be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
1434be5975aSDavid Howells next->fl_u.afs.state = AFS_LOCK_YOUR_TRY;
144d4696601SDavid Howells trace_afs_flock_op(vnode, next, afs_flock_op_wake);
1454be5975aSDavid Howells wake_up(&next->fl_wait);
1464be5975aSDavid Howells } else {
1474be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_NONE);
148d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_no_lockers, 0);
1494be5975aSDavid Howells }
1504be5975aSDavid Howells
1514be5975aSDavid Howells _leave("");
152ff8e210aSDavid Howells }
153ff8e210aSDavid Howells
154ff8e210aSDavid Howells /*
155cdfb26b4SDavid Howells * Kill off all waiters in the the pending lock queue due to the vnode being
156cdfb26b4SDavid Howells * deleted.
157cdfb26b4SDavid Howells */
afs_kill_lockers_enoent(struct afs_vnode * vnode)158cdfb26b4SDavid Howells static void afs_kill_lockers_enoent(struct afs_vnode *vnode)
159cdfb26b4SDavid Howells {
160cdfb26b4SDavid Howells struct file_lock *p;
161cdfb26b4SDavid Howells
162cdfb26b4SDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_DELETED);
163cdfb26b4SDavid Howells
164cdfb26b4SDavid Howells while (!list_empty(&vnode->pending_locks)) {
165cdfb26b4SDavid Howells p = list_entry(vnode->pending_locks.next,
166cdfb26b4SDavid Howells struct file_lock, fl_u.afs.link);
167cdfb26b4SDavid Howells list_del_init(&p->fl_u.afs.link);
168cdfb26b4SDavid Howells p->fl_u.afs.state = -ENOENT;
169cdfb26b4SDavid Howells wake_up(&p->fl_wait);
170cdfb26b4SDavid Howells }
171cdfb26b4SDavid Howells
172cdfb26b4SDavid Howells key_put(vnode->lock_key);
173cdfb26b4SDavid Howells vnode->lock_key = NULL;
174e8d6c554SDavid Howells }
175e8d6c554SDavid Howells
afs_lock_success(struct afs_operation * op)176e49c7b2fSDavid Howells static void afs_lock_success(struct afs_operation *op)
177e49c7b2fSDavid Howells {
178e49c7b2fSDavid Howells _enter("op=%08x", op->debug_id);
179e49c7b2fSDavid Howells afs_vnode_commit_status(op, &op->file[0]);
180e49c7b2fSDavid Howells }
181e49c7b2fSDavid Howells
182e49c7b2fSDavid Howells static const struct afs_operation_ops afs_set_lock_operation = {
183e49c7b2fSDavid Howells .issue_afs_rpc = afs_fs_set_lock,
184e49c7b2fSDavid Howells .issue_yfs_rpc = yfs_fs_set_lock,
185e49c7b2fSDavid Howells .success = afs_lock_success,
186728279a5SDavid Howells .aborted = afs_check_for_remote_deletion,
187e49c7b2fSDavid Howells };
188e49c7b2fSDavid Howells
189e8d6c554SDavid Howells /*
190d2ddc776SDavid Howells * Get a lock on a file
191d2ddc776SDavid Howells */
afs_set_lock(struct afs_vnode * vnode,struct key * key,afs_lock_type_t type)192d2ddc776SDavid Howells static int afs_set_lock(struct afs_vnode *vnode, struct key *key,
193d2ddc776SDavid Howells afs_lock_type_t type)
194d2ddc776SDavid Howells {
195e49c7b2fSDavid Howells struct afs_operation *op;
196d2ddc776SDavid Howells
1973b6492dfSDavid Howells _enter("%s{%llx:%llu.%u},%x,%u",
198d2ddc776SDavid Howells vnode->volume->name,
199d2ddc776SDavid Howells vnode->fid.vid,
200d2ddc776SDavid Howells vnode->fid.vnode,
201d2ddc776SDavid Howells vnode->fid.unique,
202d2ddc776SDavid Howells key_serial(key), type);
203d2ddc776SDavid Howells
204e49c7b2fSDavid Howells op = afs_alloc_operation(key, vnode->volume);
205e49c7b2fSDavid Howells if (IS_ERR(op))
206e49c7b2fSDavid Howells return PTR_ERR(op);
207a58823acSDavid Howells
208e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode);
209e49c7b2fSDavid Howells
210e49c7b2fSDavid Howells op->lock.type = type;
211e49c7b2fSDavid Howells op->ops = &afs_set_lock_operation;
212e49c7b2fSDavid Howells return afs_do_sync_operation(op);
213d2ddc776SDavid Howells }
214d2ddc776SDavid Howells
215e49c7b2fSDavid Howells static const struct afs_operation_ops afs_extend_lock_operation = {
216e49c7b2fSDavid Howells .issue_afs_rpc = afs_fs_extend_lock,
217e49c7b2fSDavid Howells .issue_yfs_rpc = yfs_fs_extend_lock,
218e49c7b2fSDavid Howells .success = afs_lock_success,
219e49c7b2fSDavid Howells };
220d2ddc776SDavid Howells
221d2ddc776SDavid Howells /*
222d2ddc776SDavid Howells * Extend a lock on a file
223d2ddc776SDavid Howells */
afs_extend_lock(struct afs_vnode * vnode,struct key * key)224d2ddc776SDavid Howells static int afs_extend_lock(struct afs_vnode *vnode, struct key *key)
225d2ddc776SDavid Howells {
226e49c7b2fSDavid Howells struct afs_operation *op;
227d2ddc776SDavid Howells
2283b6492dfSDavid Howells _enter("%s{%llx:%llu.%u},%x",
229d2ddc776SDavid Howells vnode->volume->name,
230d2ddc776SDavid Howells vnode->fid.vid,
231d2ddc776SDavid Howells vnode->fid.vnode,
232d2ddc776SDavid Howells vnode->fid.unique,
233d2ddc776SDavid Howells key_serial(key));
234d2ddc776SDavid Howells
235e49c7b2fSDavid Howells op = afs_alloc_operation(key, vnode->volume);
236e49c7b2fSDavid Howells if (IS_ERR(op))
237e49c7b2fSDavid Howells return PTR_ERR(op);
238a58823acSDavid Howells
239e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode);
240e49c7b2fSDavid Howells
241e49c7b2fSDavid Howells op->flags |= AFS_OPERATION_UNINTR;
242e49c7b2fSDavid Howells op->ops = &afs_extend_lock_operation;
243e49c7b2fSDavid Howells return afs_do_sync_operation(op);
244d2ddc776SDavid Howells }
245d2ddc776SDavid Howells
246e49c7b2fSDavid Howells static const struct afs_operation_ops afs_release_lock_operation = {
247e49c7b2fSDavid Howells .issue_afs_rpc = afs_fs_release_lock,
248e49c7b2fSDavid Howells .issue_yfs_rpc = yfs_fs_release_lock,
249e49c7b2fSDavid Howells .success = afs_lock_success,
250e49c7b2fSDavid Howells };
251d2ddc776SDavid Howells
252d2ddc776SDavid Howells /*
253d2ddc776SDavid Howells * Release a lock on a file
254d2ddc776SDavid Howells */
afs_release_lock(struct afs_vnode * vnode,struct key * key)255d2ddc776SDavid Howells static int afs_release_lock(struct afs_vnode *vnode, struct key *key)
256d2ddc776SDavid Howells {
257e49c7b2fSDavid Howells struct afs_operation *op;
258d2ddc776SDavid Howells
2593b6492dfSDavid Howells _enter("%s{%llx:%llu.%u},%x",
260d2ddc776SDavid Howells vnode->volume->name,
261d2ddc776SDavid Howells vnode->fid.vid,
262d2ddc776SDavid Howells vnode->fid.vnode,
263d2ddc776SDavid Howells vnode->fid.unique,
264d2ddc776SDavid Howells key_serial(key));
265d2ddc776SDavid Howells
266e49c7b2fSDavid Howells op = afs_alloc_operation(key, vnode->volume);
267e49c7b2fSDavid Howells if (IS_ERR(op))
268e49c7b2fSDavid Howells return PTR_ERR(op);
269a58823acSDavid Howells
270e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode);
271d2ddc776SDavid Howells
272e49c7b2fSDavid Howells op->flags |= AFS_OPERATION_UNINTR;
273e49c7b2fSDavid Howells op->ops = &afs_release_lock_operation;
274e49c7b2fSDavid Howells return afs_do_sync_operation(op);
275d2ddc776SDavid Howells }
276d2ddc776SDavid Howells
277d2ddc776SDavid Howells /*
278e8d6c554SDavid Howells * do work for a lock, including:
279e8d6c554SDavid Howells * - probing for a lock we're waiting on but didn't get immediately
280e8d6c554SDavid Howells * - extending a lock that's close to timing out
281e8d6c554SDavid Howells */
afs_lock_work(struct work_struct * work)282e8d6c554SDavid Howells void afs_lock_work(struct work_struct *work)
283e8d6c554SDavid Howells {
284e8d6c554SDavid Howells struct afs_vnode *vnode =
285e8d6c554SDavid Howells container_of(work, struct afs_vnode, lock_work.work);
286e8d6c554SDavid Howells struct key *key;
287e8d6c554SDavid Howells int ret;
288e8d6c554SDavid Howells
2893b6492dfSDavid Howells _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
290e8d6c554SDavid Howells
291e8d6c554SDavid Howells spin_lock(&vnode->lock);
292e8d6c554SDavid Howells
2930fafdc9fSDavid Howells again:
2940fafdc9fSDavid Howells _debug("wstate %u for %p", vnode->lock_state, vnode);
2950fafdc9fSDavid Howells switch (vnode->lock_state) {
2960fafdc9fSDavid Howells case AFS_VNODE_LOCK_NEED_UNLOCK:
2974be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_UNLOCKING);
298d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_work_unlocking, 0);
299e8d6c554SDavid Howells spin_unlock(&vnode->lock);
300e8d6c554SDavid Howells
301e8d6c554SDavid Howells /* attempt to release the server lock; if it fails, we just
3020fafdc9fSDavid Howells * wait 5 minutes and it'll expire anyway */
3030fafdc9fSDavid Howells ret = afs_release_lock(vnode, vnode->lock_key);
30479ddbfa5SDavid Howells if (ret < 0 && vnode->lock_state != AFS_VNODE_LOCK_DELETED) {
305cdfb26b4SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_release_fail,
306cdfb26b4SDavid Howells ret);
307e8d6c554SDavid Howells printk(KERN_WARNING "AFS:"
3083b6492dfSDavid Howells " Failed to release lock on {%llx:%llx} error %d\n",
309e8d6c554SDavid Howells vnode->fid.vid, vnode->fid.vnode, ret);
310e8d6c554SDavid Howells }
311e8d6c554SDavid Howells
312e8d6c554SDavid Howells spin_lock(&vnode->lock);
313cdfb26b4SDavid Howells if (ret == -ENOENT)
314cdfb26b4SDavid Howells afs_kill_lockers_enoent(vnode);
315cdfb26b4SDavid Howells else
3164be5975aSDavid Howells afs_next_locker(vnode, 0);
317e8d6c554SDavid Howells spin_unlock(&vnode->lock);
318e8d6c554SDavid Howells return;
3190fafdc9fSDavid Howells
3200fafdc9fSDavid Howells /* If we've already got a lock, then it must be time to extend that
3210fafdc9fSDavid Howells * lock as AFS locks time out after 5 minutes.
3220fafdc9fSDavid Howells */
3230fafdc9fSDavid Howells case AFS_VNODE_LOCK_GRANTED:
3240fafdc9fSDavid Howells _debug("extend");
3250fafdc9fSDavid Howells
3260fafdc9fSDavid Howells ASSERT(!list_empty(&vnode->granted_locks));
3270fafdc9fSDavid Howells
3280fafdc9fSDavid Howells key = key_get(vnode->lock_key);
3294be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_EXTENDING);
330d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_work_extending, 0);
331e8d6c554SDavid Howells spin_unlock(&vnode->lock);
332e8d6c554SDavid Howells
3330fafdc9fSDavid Howells ret = afs_extend_lock(vnode, key); /* RPC */
3340fafdc9fSDavid Howells key_put(key);
3350fafdc9fSDavid Howells
336cdfb26b4SDavid Howells if (ret < 0) {
337cdfb26b4SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_extend_fail,
338cdfb26b4SDavid Howells ret);
339a4e530aeSKefeng Wang pr_warn("AFS: Failed to extend lock on {%llx:%llx} error %d\n",
3400fafdc9fSDavid Howells vnode->fid.vid, vnode->fid.vnode, ret);
341cdfb26b4SDavid Howells }
3420fafdc9fSDavid Howells
3430fafdc9fSDavid Howells spin_lock(&vnode->lock);
3440fafdc9fSDavid Howells
345cdfb26b4SDavid Howells if (ret == -ENOENT) {
346cdfb26b4SDavid Howells afs_kill_lockers_enoent(vnode);
347cdfb26b4SDavid Howells spin_unlock(&vnode->lock);
348cdfb26b4SDavid Howells return;
349cdfb26b4SDavid Howells }
350cdfb26b4SDavid Howells
3510fafdc9fSDavid Howells if (vnode->lock_state != AFS_VNODE_LOCK_EXTENDING)
3520fafdc9fSDavid Howells goto again;
3534be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_GRANTED);
3540fafdc9fSDavid Howells
3554be5975aSDavid Howells if (ret != 0)
3560fafdc9fSDavid Howells queue_delayed_work(afs_lock_manager, &vnode->lock_work,
3570fafdc9fSDavid Howells HZ * 10);
3580fafdc9fSDavid Howells spin_unlock(&vnode->lock);
3590fafdc9fSDavid Howells _leave(" [ext]");
3600fafdc9fSDavid Howells return;
3610fafdc9fSDavid Howells
3624be5975aSDavid Howells /* If we're waiting for a callback to indicate lock release, we can't
3634be5975aSDavid Howells * actually rely on this, so need to recheck at regular intervals. The
3644be5975aSDavid Howells * problem is that the server might not notify us if the lock just
3654be5975aSDavid Howells * expires (say because a client died) rather than being explicitly
3664be5975aSDavid Howells * released.
3670fafdc9fSDavid Howells */
3680fafdc9fSDavid Howells case AFS_VNODE_LOCK_WAITING_FOR_CB:
3694be5975aSDavid Howells _debug("retry");
3704be5975aSDavid Howells afs_next_locker(vnode, 0);
3710fafdc9fSDavid Howells spin_unlock(&vnode->lock);
372e8d6c554SDavid Howells return;
373e8d6c554SDavid Howells
374cdfb26b4SDavid Howells case AFS_VNODE_LOCK_DELETED:
375cdfb26b4SDavid Howells afs_kill_lockers_enoent(vnode);
376cdfb26b4SDavid Howells spin_unlock(&vnode->lock);
377cdfb26b4SDavid Howells return;
378e8d6c554SDavid Howells
3790fafdc9fSDavid Howells default:
3800fafdc9fSDavid Howells /* Looks like a lock request was withdrawn. */
381e8d6c554SDavid Howells spin_unlock(&vnode->lock);
3820fafdc9fSDavid Howells _leave(" [no]");
3830fafdc9fSDavid Howells return;
3840fafdc9fSDavid Howells }
385e8d6c554SDavid Howells }
386e8d6c554SDavid Howells
387e8d6c554SDavid Howells /*
388e8d6c554SDavid Howells * pass responsibility for the unlocking of a vnode on the server to the
389e8d6c554SDavid Howells * manager thread, lest a pending signal in the calling thread interrupt
390e8d6c554SDavid Howells * AF_RXRPC
391e8d6c554SDavid Howells * - the caller must hold the vnode lock
392e8d6c554SDavid Howells */
afs_defer_unlock(struct afs_vnode * vnode)3930fafdc9fSDavid Howells static void afs_defer_unlock(struct afs_vnode *vnode)
394e8d6c554SDavid Howells {
3954be5975aSDavid Howells _enter("%u", vnode->lock_state);
3960fafdc9fSDavid Howells
3974be5975aSDavid Howells if (list_empty(&vnode->granted_locks) &&
3984be5975aSDavid Howells (vnode->lock_state == AFS_VNODE_LOCK_GRANTED ||
3994be5975aSDavid Howells vnode->lock_state == AFS_VNODE_LOCK_EXTENDING)) {
400e8d6c554SDavid Howells cancel_delayed_work(&vnode->lock_work);
4010fafdc9fSDavid Howells
4024be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_NEED_UNLOCK);
403d4696601SDavid Howells trace_afs_flock_ev(vnode, NULL, afs_flock_defer_unlock, 0);
4044be5975aSDavid Howells queue_delayed_work(afs_lock_manager, &vnode->lock_work, 0);
4050fafdc9fSDavid Howells }
4060fafdc9fSDavid Howells }
4070fafdc9fSDavid Howells
4080fafdc9fSDavid Howells /*
4090fafdc9fSDavid Howells * Check that our view of the file metadata is up to date and check to see
4100fafdc9fSDavid Howells * whether we think that we have a locking permit.
4110fafdc9fSDavid Howells */
afs_do_setlk_check(struct afs_vnode * vnode,struct key * key,enum afs_flock_mode mode,afs_lock_type_t type)4120fafdc9fSDavid Howells static int afs_do_setlk_check(struct afs_vnode *vnode, struct key *key,
4136c6c1d63SDavid Howells enum afs_flock_mode mode, afs_lock_type_t type)
4140fafdc9fSDavid Howells {
4150fafdc9fSDavid Howells afs_access_t access;
4160fafdc9fSDavid Howells int ret;
4170fafdc9fSDavid Howells
4180fafdc9fSDavid Howells /* Make sure we've got a callback on this file and that our view of the
4190fafdc9fSDavid Howells * data version is up to date.
4200fafdc9fSDavid Howells */
4210fafdc9fSDavid Howells ret = afs_validate(vnode, key);
4220fafdc9fSDavid Howells if (ret < 0)
4230fafdc9fSDavid Howells return ret;
4240fafdc9fSDavid Howells
4250fafdc9fSDavid Howells /* Check the permission set to see if we're actually going to be
4260fafdc9fSDavid Howells * allowed to get a lock on this file.
4270fafdc9fSDavid Howells */
4280fafdc9fSDavid Howells ret = afs_check_permit(vnode, key, &access);
4290fafdc9fSDavid Howells if (ret < 0)
4300fafdc9fSDavid Howells return ret;
4310fafdc9fSDavid Howells
4320fafdc9fSDavid Howells /* At a rough estimation, you need LOCK, WRITE or INSERT perm to
4330fafdc9fSDavid Howells * read-lock a file and WRITE or INSERT perm to write-lock a file.
4340fafdc9fSDavid Howells *
4350fafdc9fSDavid Howells * We can't rely on the server to do this for us since if we want to
4360fafdc9fSDavid Howells * share a read lock that we already have, we won't go the server.
4370fafdc9fSDavid Howells */
4380fafdc9fSDavid Howells if (type == AFS_LOCK_READ) {
4390fafdc9fSDavid Howells if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE | AFS_ACE_LOCK)))
4400fafdc9fSDavid Howells return -EACCES;
4410fafdc9fSDavid Howells } else {
4420fafdc9fSDavid Howells if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE)))
4430fafdc9fSDavid Howells return -EACCES;
4440fafdc9fSDavid Howells }
4450fafdc9fSDavid Howells
4460fafdc9fSDavid Howells return 0;
4470fafdc9fSDavid Howells }
4480fafdc9fSDavid Howells
4490fafdc9fSDavid Howells /*
450e8d6c554SDavid Howells * request a lock on a file on the server
451e8d6c554SDavid Howells */
afs_do_setlk(struct file * file,struct file_lock * fl)452e8d6c554SDavid Howells static int afs_do_setlk(struct file *file, struct file_lock *fl)
453e8d6c554SDavid Howells {
454*c65454a9SJeff Layton struct inode *inode = file_inode(file);
4551c8c601aSJeff Layton struct afs_vnode *vnode = AFS_FS_I(inode);
4566c6c1d63SDavid Howells enum afs_flock_mode mode = AFS_FS_S(inode->i_sb)->flock_mode;
457e8d6c554SDavid Howells afs_lock_type_t type;
458215804a9SDavid Howells struct key *key = afs_file_key(file);
4596c6c1d63SDavid Howells bool partial, no_server_lock = false;
460e8d6c554SDavid Howells int ret;
461e8d6c554SDavid Howells
4626c6c1d63SDavid Howells if (mode == afs_flock_mode_unset)
4636c6c1d63SDavid Howells mode = afs_flock_mode_openafs;
464e8d6c554SDavid Howells
4656c6c1d63SDavid Howells _enter("{%llx:%llu},%llu-%llu,%u,%u",
4666c6c1d63SDavid Howells vnode->fid.vid, vnode->fid.vnode,
4676c6c1d63SDavid Howells fl->fl_start, fl->fl_end, fl->fl_type, mode);
468e8d6c554SDavid Howells
469e8d6c554SDavid Howells fl->fl_ops = &afs_lock_ops;
470e8d6c554SDavid Howells INIT_LIST_HEAD(&fl->fl_u.afs.link);
471e8d6c554SDavid Howells fl->fl_u.afs.state = AFS_LOCK_PENDING;
472e8d6c554SDavid Howells
4736c6c1d63SDavid Howells partial = (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX);
474e8d6c554SDavid Howells type = (fl->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE;
4756c6c1d63SDavid Howells if (mode == afs_flock_mode_write && partial)
4766c6c1d63SDavid Howells type = AFS_LOCK_WRITE;
477e8d6c554SDavid Howells
4786c6c1d63SDavid Howells ret = afs_do_setlk_check(vnode, key, mode, type);
479e8d6c554SDavid Howells if (ret < 0)
4800fafdc9fSDavid Howells return ret;
481e8d6c554SDavid Howells
482d4696601SDavid Howells trace_afs_flock_op(vnode, fl, afs_flock_op_set_lock);
483e8d6c554SDavid Howells
4846c6c1d63SDavid Howells /* AFS3 protocol only supports full-file locks and doesn't provide any
4856c6c1d63SDavid Howells * method of upgrade/downgrade, so we need to emulate for partial-file
4866c6c1d63SDavid Howells * locks.
4876c6c1d63SDavid Howells *
4886c6c1d63SDavid Howells * The OpenAFS client only gets a server lock for a full-file lock and
4896c6c1d63SDavid Howells * keeps partial-file locks local. Allow this behaviour to be emulated
4906c6c1d63SDavid Howells * (as the default).
4910fafdc9fSDavid Howells */
4926c6c1d63SDavid Howells if (mode == afs_flock_mode_local ||
4936c6c1d63SDavid Howells (partial && mode == afs_flock_mode_openafs)) {
4946c6c1d63SDavid Howells no_server_lock = true;
4956c6c1d63SDavid Howells goto skip_server_lock;
496ff8e210aSDavid Howells }
497ff8e210aSDavid Howells
498e8d6c554SDavid Howells spin_lock(&vnode->lock);
499e8d6c554SDavid Howells list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks);
5000fafdc9fSDavid Howells
501cdfb26b4SDavid Howells ret = -ENOENT;
502cdfb26b4SDavid Howells if (vnode->lock_state == AFS_VNODE_LOCK_DELETED)
503cdfb26b4SDavid Howells goto error_unlock;
504cdfb26b4SDavid Howells
5054be5975aSDavid Howells /* If we've already got a lock on the server then try to move to having
5064be5975aSDavid Howells * the VFS grant the requested lock. Note that this means that other
5074be5975aSDavid Howells * clients may get starved out.
508e8d6c554SDavid Howells */
5094be5975aSDavid Howells _debug("try %u", vnode->lock_state);
5104be5975aSDavid Howells if (vnode->lock_state == AFS_VNODE_LOCK_GRANTED) {
5114be5975aSDavid Howells if (type == AFS_LOCK_READ) {
512e8d6c554SDavid Howells _debug("instant readlock");
5134be5975aSDavid Howells list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks);
5144be5975aSDavid Howells fl->fl_u.afs.state = AFS_LOCK_GRANTED;
5154be5975aSDavid Howells goto vnode_is_locked_u;
516e8d6c554SDavid Howells }
517e8d6c554SDavid Howells
5184be5975aSDavid Howells if (vnode->lock_type == AFS_LOCK_WRITE) {
5194be5975aSDavid Howells _debug("instant writelock");
5204be5975aSDavid Howells list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks);
5214be5975aSDavid Howells fl->fl_u.afs.state = AFS_LOCK_GRANTED;
5224be5975aSDavid Howells goto vnode_is_locked_u;
5234be5975aSDavid Howells }
5244be5975aSDavid Howells }
5250fafdc9fSDavid Howells
5266c6c1d63SDavid Howells if (vnode->lock_state == AFS_VNODE_LOCK_NONE &&
5276c6c1d63SDavid Howells !(fl->fl_flags & FL_SLEEP)) {
5286c6c1d63SDavid Howells ret = -EAGAIN;
5296c6c1d63SDavid Howells if (type == AFS_LOCK_READ) {
5306c6c1d63SDavid Howells if (vnode->status.lock_count == -1)
5316c6c1d63SDavid Howells goto lock_is_contended; /* Write locked */
5326c6c1d63SDavid Howells } else {
5336c6c1d63SDavid Howells if (vnode->status.lock_count != 0)
5346c6c1d63SDavid Howells goto lock_is_contended; /* Locked */
5356c6c1d63SDavid Howells }
5366c6c1d63SDavid Howells }
5376c6c1d63SDavid Howells
5380fafdc9fSDavid Howells if (vnode->lock_state != AFS_VNODE_LOCK_NONE)
5390fafdc9fSDavid Howells goto need_to_wait;
5400fafdc9fSDavid Howells
5414be5975aSDavid Howells try_to_lock:
5420fafdc9fSDavid Howells /* We don't have a lock on this vnode and we aren't currently waiting
5430fafdc9fSDavid Howells * for one either, so ask the server for a lock.
5440fafdc9fSDavid Howells *
5450fafdc9fSDavid Howells * Note that we need to be careful if we get interrupted by a signal
5460fafdc9fSDavid Howells * after dispatching the request as we may still get the lock, even
5470fafdc9fSDavid Howells * though we don't wait for the reply (it's not too bad a problem - the
5484be5975aSDavid Howells * lock will expire in 5 mins anyway).
5490fafdc9fSDavid Howells */
550d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_try_to_lock, 0);
5510fafdc9fSDavid Howells vnode->lock_key = key_get(key);
5520fafdc9fSDavid Howells vnode->lock_type = type;
5534be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
554e8d6c554SDavid Howells spin_unlock(&vnode->lock);
555e8d6c554SDavid Howells
5560fafdc9fSDavid Howells ret = afs_set_lock(vnode, key, type); /* RPC */
5570fafdc9fSDavid Howells
5580fafdc9fSDavid Howells spin_lock(&vnode->lock);
559e8d6c554SDavid Howells switch (ret) {
5604be5975aSDavid Howells case -EKEYREJECTED:
5614be5975aSDavid Howells case -EKEYEXPIRED:
5624be5975aSDavid Howells case -EKEYREVOKED:
5634be5975aSDavid Howells case -EPERM:
5644be5975aSDavid Howells case -EACCES:
5654be5975aSDavid Howells fl->fl_u.afs.state = ret;
566d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_fail_perm, ret);
5674be5975aSDavid Howells list_del_init(&fl->fl_u.afs.link);
5684be5975aSDavid Howells afs_next_locker(vnode, ret);
5694be5975aSDavid Howells goto error_unlock;
5704be5975aSDavid Howells
571cdfb26b4SDavid Howells case -ENOENT:
572cdfb26b4SDavid Howells fl->fl_u.afs.state = ret;
573cdfb26b4SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_fail_other, ret);
574cdfb26b4SDavid Howells list_del_init(&fl->fl_u.afs.link);
575cdfb26b4SDavid Howells afs_kill_lockers_enoent(vnode);
576cdfb26b4SDavid Howells goto error_unlock;
577cdfb26b4SDavid Howells
5780fafdc9fSDavid Howells default:
5794be5975aSDavid Howells fl->fl_u.afs.state = ret;
580d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_fail_other, ret);
5814be5975aSDavid Howells list_del_init(&fl->fl_u.afs.link);
5824be5975aSDavid Howells afs_next_locker(vnode, 0);
5834be5975aSDavid Howells goto error_unlock;
5840fafdc9fSDavid Howells
5850fafdc9fSDavid Howells case -EWOULDBLOCK:
5860fafdc9fSDavid Howells /* The server doesn't have a lock-waiting queue, so the client
5870fafdc9fSDavid Howells * will have to retry. The server will break the outstanding
5880fafdc9fSDavid Howells * callbacks on a file when a lock is released.
5890fafdc9fSDavid Howells */
5900fafdc9fSDavid Howells ASSERT(list_empty(&vnode->granted_locks));
5910fafdc9fSDavid Howells ASSERTCMP(vnode->pending_locks.next, ==, &fl->fl_u.afs.link);
5924be5975aSDavid Howells goto lock_is_contended;
5930fafdc9fSDavid Howells
594e8d6c554SDavid Howells case 0:
5954be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_GRANTED);
596d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_acquired, type);
5974be5975aSDavid Howells afs_grant_locks(vnode);
5984be5975aSDavid Howells goto vnode_is_locked_u;
599e8d6c554SDavid Howells }
600e8d6c554SDavid Howells
6014be5975aSDavid Howells vnode_is_locked_u:
6020fafdc9fSDavid Howells spin_unlock(&vnode->lock);
6034be5975aSDavid Howells vnode_is_locked:
6044be5975aSDavid Howells /* the lock has been granted by the server... */
6054be5975aSDavid Howells ASSERTCMP(fl->fl_u.afs.state, ==, AFS_LOCK_GRANTED);
6060fafdc9fSDavid Howells
6076c6c1d63SDavid Howells skip_server_lock:
6084be5975aSDavid Howells /* ... but the VFS still needs to distribute access on this client. */
609d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_vfs_locking, 0);
6104be5975aSDavid Howells ret = locks_lock_file_wait(file, fl);
611d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_vfs_lock, ret);
6120fafdc9fSDavid Howells if (ret < 0)
6130fafdc9fSDavid Howells goto vfs_rejected_lock;
6140fafdc9fSDavid Howells
6150fafdc9fSDavid Howells /* Again, make sure we've got a callback on this file and, again, make
6160fafdc9fSDavid Howells * sure that our view of the data version is up to date (we ignore
6170fafdc9fSDavid Howells * errors incurred here and deal with the consequences elsewhere).
6180fafdc9fSDavid Howells */
6190fafdc9fSDavid Howells afs_validate(vnode, key);
6200fafdc9fSDavid Howells _leave(" = 0");
6210fafdc9fSDavid Howells return 0;
6220fafdc9fSDavid Howells
6234be5975aSDavid Howells lock_is_contended:
6244be5975aSDavid Howells if (!(fl->fl_flags & FL_SLEEP)) {
6254be5975aSDavid Howells list_del_init(&fl->fl_u.afs.link);
6264be5975aSDavid Howells afs_next_locker(vnode, 0);
6274be5975aSDavid Howells ret = -EAGAIN;
6284be5975aSDavid Howells goto error_unlock;
6294be5975aSDavid Howells }
6304be5975aSDavid Howells
6314be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_WAITING_FOR_CB);
632d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_would_block, ret);
6334be5975aSDavid Howells queue_delayed_work(afs_lock_manager, &vnode->lock_work, HZ * 5);
6344be5975aSDavid Howells
6350fafdc9fSDavid Howells need_to_wait:
6360fafdc9fSDavid Howells /* We're going to have to wait. Either this client doesn't have a lock
6370fafdc9fSDavid Howells * on the server yet and we need to wait for a callback to occur, or
6384be5975aSDavid Howells * the client does have a lock on the server, but it's shared and we
6394be5975aSDavid Howells * need an exclusive lock.
6400fafdc9fSDavid Howells */
641e8d6c554SDavid Howells spin_unlock(&vnode->lock);
642e8d6c554SDavid Howells
643d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_waiting, 0);
644e8d6c554SDavid Howells ret = wait_event_interruptible(fl->fl_wait,
6450fafdc9fSDavid Howells fl->fl_u.afs.state != AFS_LOCK_PENDING);
646d4696601SDavid Howells trace_afs_flock_ev(vnode, fl, afs_flock_waited, ret);
647e8d6c554SDavid Howells
6484be5975aSDavid Howells if (fl->fl_u.afs.state >= 0 && fl->fl_u.afs.state != AFS_LOCK_GRANTED) {
649e8d6c554SDavid Howells spin_lock(&vnode->lock);
6504be5975aSDavid Howells
6514be5975aSDavid Howells switch (fl->fl_u.afs.state) {
6524be5975aSDavid Howells case AFS_LOCK_YOUR_TRY:
6534be5975aSDavid Howells fl->fl_u.afs.state = AFS_LOCK_PENDING;
6544be5975aSDavid Howells goto try_to_lock;
6554be5975aSDavid Howells case AFS_LOCK_PENDING:
6564be5975aSDavid Howells if (ret > 0) {
6574be5975aSDavid Howells /* We need to retry the lock. We may not be
6584be5975aSDavid Howells * notified by the server if it just expired
6594be5975aSDavid Howells * rather than being released.
6604be5975aSDavid Howells */
6614be5975aSDavid Howells ASSERTCMP(vnode->lock_state, ==, AFS_VNODE_LOCK_WAITING_FOR_CB);
6624be5975aSDavid Howells afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
6634be5975aSDavid Howells fl->fl_u.afs.state = AFS_LOCK_PENDING;
6644be5975aSDavid Howells goto try_to_lock;
6654be5975aSDavid Howells }
6664be5975aSDavid Howells goto error_unlock;
6674be5975aSDavid Howells case AFS_LOCK_GRANTED:
6684be5975aSDavid Howells default:
6694be5975aSDavid Howells break;
6704be5975aSDavid Howells }
6714be5975aSDavid Howells
6724be5975aSDavid Howells spin_unlock(&vnode->lock);
673e8d6c554SDavid Howells }
6740fafdc9fSDavid Howells
6750fafdc9fSDavid Howells if (fl->fl_u.afs.state == AFS_LOCK_GRANTED)
6764be5975aSDavid Howells goto vnode_is_locked;
6770fafdc9fSDavid Howells ret = fl->fl_u.afs.state;
6784be5975aSDavid Howells goto error;
679e8d6c554SDavid Howells
680e8d6c554SDavid Howells vfs_rejected_lock:
6810fafdc9fSDavid Howells /* The VFS rejected the lock we just obtained, so we have to discard
6820fafdc9fSDavid Howells * what we just got. We defer this to the lock manager work item to
6830fafdc9fSDavid Howells * deal with.
6840fafdc9fSDavid Howells */
685e8d6c554SDavid Howells _debug("vfs refused %d", ret);
6866c6c1d63SDavid Howells if (no_server_lock)
6876c6c1d63SDavid Howells goto error;
6880fafdc9fSDavid Howells spin_lock(&vnode->lock);
689e8d6c554SDavid Howells list_del_init(&fl->fl_u.afs.link);
6900fafdc9fSDavid Howells afs_defer_unlock(vnode);
6914be5975aSDavid Howells
6924be5975aSDavid Howells error_unlock:
6934be5975aSDavid Howells spin_unlock(&vnode->lock);
6944be5975aSDavid Howells error:
6954be5975aSDavid Howells _leave(" = %d", ret);
6964be5975aSDavid Howells return ret;
697e8d6c554SDavid Howells }
698e8d6c554SDavid Howells
699e8d6c554SDavid Howells /*
700e8d6c554SDavid Howells * unlock on a file on the server
701e8d6c554SDavid Howells */
afs_do_unlk(struct file * file,struct file_lock * fl)702e8d6c554SDavid Howells static int afs_do_unlk(struct file *file, struct file_lock *fl)
703e8d6c554SDavid Howells {
704*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
705e8d6c554SDavid Howells int ret;
706e8d6c554SDavid Howells
7073b6492dfSDavid Howells _enter("{%llx:%llu},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
708e8d6c554SDavid Howells
709d4696601SDavid Howells trace_afs_flock_op(vnode, fl, afs_flock_op_unlock);
710d4696601SDavid Howells
7110fafdc9fSDavid Howells /* Flush all pending writes before doing anything with locks. */
7120fafdc9fSDavid Howells vfs_fsync(file, 0);
7130fafdc9fSDavid Howells
7144be5975aSDavid Howells ret = locks_lock_file_wait(file, fl);
7150fafdc9fSDavid Howells _leave(" = %d [%u]", ret, vnode->lock_state);
716e8d6c554SDavid Howells return ret;
717e8d6c554SDavid Howells }
718e8d6c554SDavid Howells
719e8d6c554SDavid Howells /*
720e8d6c554SDavid Howells * return information about a lock we currently hold, if indeed we hold one
721e8d6c554SDavid Howells */
afs_do_getlk(struct file * file,struct file_lock * fl)722e8d6c554SDavid Howells static int afs_do_getlk(struct file *file, struct file_lock *fl)
723e8d6c554SDavid Howells {
724*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
725215804a9SDavid Howells struct key *key = afs_file_key(file);
726e8d6c554SDavid Howells int ret, lock_count;
727e8d6c554SDavid Howells
728e8d6c554SDavid Howells _enter("");
729e8d6c554SDavid Howells
730cdfb26b4SDavid Howells if (vnode->lock_state == AFS_VNODE_LOCK_DELETED)
731cdfb26b4SDavid Howells return -ENOENT;
732cdfb26b4SDavid Howells
733e8d6c554SDavid Howells fl->fl_type = F_UNLCK;
734e8d6c554SDavid Howells
735e8d6c554SDavid Howells /* check local lock records first */
736275afcacSAndrew Morton posix_test_lock(file, fl);
737275afcacSAndrew Morton if (fl->fl_type == F_UNLCK) {
738e8d6c554SDavid Howells /* no local locks; consult the server */
739a58823acSDavid Howells ret = afs_fetch_status(vnode, key, false, NULL);
740e8d6c554SDavid Howells if (ret < 0)
741e8d6c554SDavid Howells goto error;
7420fafdc9fSDavid Howells
7430fafdc9fSDavid Howells lock_count = READ_ONCE(vnode->status.lock_count);
74468ce801fSDavid Howells if (lock_count != 0) {
745e8d6c554SDavid Howells if (lock_count > 0)
746e8d6c554SDavid Howells fl->fl_type = F_RDLCK;
747e8d6c554SDavid Howells else
748e8d6c554SDavid Howells fl->fl_type = F_WRLCK;
749e8d6c554SDavid Howells fl->fl_start = 0;
750e8d6c554SDavid Howells fl->fl_end = OFFSET_MAX;
75168ce801fSDavid Howells fl->fl_pid = 0;
75268ce801fSDavid Howells }
753e8d6c554SDavid Howells }
754e8d6c554SDavid Howells
7550fafdc9fSDavid Howells ret = 0;
756e8d6c554SDavid Howells error:
757e8d6c554SDavid Howells _leave(" = %d [%hd]", ret, fl->fl_type);
758e8d6c554SDavid Howells return ret;
759e8d6c554SDavid Howells }
760e8d6c554SDavid Howells
761e8d6c554SDavid Howells /*
762e8d6c554SDavid Howells * manage POSIX locks on a file
763e8d6c554SDavid Howells */
afs_lock(struct file * file,int cmd,struct file_lock * fl)764e8d6c554SDavid Howells int afs_lock(struct file *file, int cmd, struct file_lock *fl)
765e8d6c554SDavid Howells {
766*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
767d4696601SDavid Howells enum afs_flock_operation op;
768d4696601SDavid Howells int ret;
769e8d6c554SDavid Howells
7703b6492dfSDavid Howells _enter("{%llx:%llu},%d,{t=%x,fl=%x,r=%Ld:%Ld}",
771e8d6c554SDavid Howells vnode->fid.vid, vnode->fid.vnode, cmd,
772e8d6c554SDavid Howells fl->fl_type, fl->fl_flags,
773e8d6c554SDavid Howells (long long) fl->fl_start, (long long) fl->fl_end);
774e8d6c554SDavid Howells
775e8d6c554SDavid Howells if (IS_GETLK(cmd))
776e8d6c554SDavid Howells return afs_do_getlk(file, fl);
777d4696601SDavid Howells
778d4696601SDavid Howells fl->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
779d4696601SDavid Howells trace_afs_flock_op(vnode, fl, afs_flock_op_lock);
780d4696601SDavid Howells
781e8d6c554SDavid Howells if (fl->fl_type == F_UNLCK)
782d4696601SDavid Howells ret = afs_do_unlk(file, fl);
783d4696601SDavid Howells else
784d4696601SDavid Howells ret = afs_do_setlk(file, fl);
785d4696601SDavid Howells
786d4696601SDavid Howells switch (ret) {
787d4696601SDavid Howells case 0: op = afs_flock_op_return_ok; break;
788d4696601SDavid Howells case -EAGAIN: op = afs_flock_op_return_eagain; break;
789d4696601SDavid Howells case -EDEADLK: op = afs_flock_op_return_edeadlk; break;
790d4696601SDavid Howells default: op = afs_flock_op_return_error; break;
791d4696601SDavid Howells }
792d4696601SDavid Howells trace_afs_flock_op(vnode, fl, op);
793d4696601SDavid Howells return ret;
794e8d6c554SDavid Howells }
795e8d6c554SDavid Howells
796e8d6c554SDavid Howells /*
797e8d6c554SDavid Howells * manage FLOCK locks on a file
798e8d6c554SDavid Howells */
afs_flock(struct file * file,int cmd,struct file_lock * fl)799e8d6c554SDavid Howells int afs_flock(struct file *file, int cmd, struct file_lock *fl)
800e8d6c554SDavid Howells {
801*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
802d4696601SDavid Howells enum afs_flock_operation op;
803d4696601SDavid Howells int ret;
804e8d6c554SDavid Howells
8053b6492dfSDavid Howells _enter("{%llx:%llu},%d,{t=%x,fl=%x}",
806e8d6c554SDavid Howells vnode->fid.vid, vnode->fid.vnode, cmd,
807e8d6c554SDavid Howells fl->fl_type, fl->fl_flags);
808e8d6c554SDavid Howells
809e8d6c554SDavid Howells /*
810e8d6c554SDavid Howells * No BSD flocks over NFS allowed.
811e8d6c554SDavid Howells * Note: we could try to fake a POSIX lock request here by
812e8d6c554SDavid Howells * using ((u32) filp | 0x80000000) or some such as the pid.
813e8d6c554SDavid Howells * Not sure whether that would be unique, though, or whether
814e8d6c554SDavid Howells * that would break in other places.
815e8d6c554SDavid Howells */
816e8d6c554SDavid Howells if (!(fl->fl_flags & FL_FLOCK))
817e8d6c554SDavid Howells return -ENOLCK;
818e8d6c554SDavid Howells
819d4696601SDavid Howells fl->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
820d4696601SDavid Howells trace_afs_flock_op(vnode, fl, afs_flock_op_flock);
821d4696601SDavid Howells
822e8d6c554SDavid Howells /* we're simulating flock() locks using posix locks on the server */
823e8d6c554SDavid Howells if (fl->fl_type == F_UNLCK)
824d4696601SDavid Howells ret = afs_do_unlk(file, fl);
825d4696601SDavid Howells else
826d4696601SDavid Howells ret = afs_do_setlk(file, fl);
827d4696601SDavid Howells
828d4696601SDavid Howells switch (ret) {
829d4696601SDavid Howells case 0: op = afs_flock_op_return_ok; break;
830d4696601SDavid Howells case -EAGAIN: op = afs_flock_op_return_eagain; break;
831d4696601SDavid Howells case -EDEADLK: op = afs_flock_op_return_edeadlk; break;
832d4696601SDavid Howells default: op = afs_flock_op_return_error; break;
833d4696601SDavid Howells }
834d4696601SDavid Howells trace_afs_flock_op(vnode, fl, op);
835d4696601SDavid Howells return ret;
836e8d6c554SDavid Howells }
837e8d6c554SDavid Howells
838e8d6c554SDavid Howells /*
839e8d6c554SDavid Howells * the POSIX lock management core VFS code copies the lock record and adds the
840e8d6c554SDavid Howells * copy into its own list, so we need to add that copy to the vnode's lock
841e8d6c554SDavid Howells * queue in the same place as the original (which will be deleted shortly
842e8d6c554SDavid Howells * after)
843e8d6c554SDavid Howells */
afs_fl_copy_lock(struct file_lock * new,struct file_lock * fl)844e8d6c554SDavid Howells static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl)
845e8d6c554SDavid Howells {
846*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(fl->fl_file));
8470fafdc9fSDavid Howells
848e8d6c554SDavid Howells _enter("");
849e8d6c554SDavid Howells
850d4696601SDavid Howells new->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
851d4696601SDavid Howells
8520fafdc9fSDavid Howells spin_lock(&vnode->lock);
853d4696601SDavid Howells trace_afs_flock_op(vnode, new, afs_flock_op_copy_lock);
854e8d6c554SDavid Howells list_add(&new->fl_u.afs.link, &fl->fl_u.afs.link);
8550fafdc9fSDavid Howells spin_unlock(&vnode->lock);
856e8d6c554SDavid Howells }
857e8d6c554SDavid Howells
858e8d6c554SDavid Howells /*
859e8d6c554SDavid Howells * need to remove this lock from the vnode queue when it's removed from the
860e8d6c554SDavid Howells * VFS's list
861e8d6c554SDavid Howells */
afs_fl_release_private(struct file_lock * fl)862e8d6c554SDavid Howells static void afs_fl_release_private(struct file_lock *fl)
863e8d6c554SDavid Howells {
864*c65454a9SJeff Layton struct afs_vnode *vnode = AFS_FS_I(file_inode(fl->fl_file));
8650fafdc9fSDavid Howells
866e8d6c554SDavid Howells _enter("");
867e8d6c554SDavid Howells
8680fafdc9fSDavid Howells spin_lock(&vnode->lock);
8694be5975aSDavid Howells
870d4696601SDavid Howells trace_afs_flock_op(vnode, fl, afs_flock_op_release_lock);
8714be5975aSDavid Howells list_del_init(&fl->fl_u.afs.link);
8724be5975aSDavid Howells if (list_empty(&vnode->granted_locks))
8734be5975aSDavid Howells afs_defer_unlock(vnode);
8744be5975aSDavid Howells
8750fafdc9fSDavid Howells _debug("state %u for %p", vnode->lock_state, vnode);
8760fafdc9fSDavid Howells spin_unlock(&vnode->lock);
877e8d6c554SDavid Howells }
878