AFS: implement file locking
Implement file locking for AFS. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Родитель
b0fed3140f
Коммит
e8d6c55412
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@ -8,6 +8,7 @@ kafs-objs := \
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cmservice.o \
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dir.o \
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file.o \
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flock.o \
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fsclient.o \
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inode.o \
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main.o \
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@ -37,6 +37,13 @@ typedef enum {
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AFS_FTYPE_SYMLINK = 3,
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} afs_file_type_t;
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typedef enum {
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AFS_LOCK_READ = 0, /* read lock request */
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AFS_LOCK_WRITE = 1, /* write lock request */
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} afs_lock_type_t;
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#define AFS_LOCKWAIT (5 * 60) /* time until a lock times out (seconds) */
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/*
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* AFS file identifier
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*/
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@ -120,6 +127,7 @@ struct afs_file_status {
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struct afs_fid parent; /* parent dir ID for non-dirs only */
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time_t mtime_client; /* last time client changed data */
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time_t mtime_server; /* last time server changed data */
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s32 lock_count; /* file lock count (0=UNLK -1=WRLCK +ve=#RDLCK */
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};
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/*
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@ -31,6 +31,9 @@ enum AFS_FS_Operations {
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FSGETVOLUMEINFO = 148, /* AFS Get information about a volume */
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FSGETVOLUMESTATUS = 149, /* AFS Get volume status information */
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FSGETROOTVOLUME = 151, /* AFS Get root volume name */
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FSSETLOCK = 156, /* AFS Request a file lock */
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FSEXTENDLOCK = 157, /* AFS Extend a file lock */
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FSRELEASELOCK = 158, /* AFS Release a file lock */
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FSLOOKUP = 161, /* AFS lookup file in directory */
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FSFETCHDATA64 = 65537, /* AFS Fetch file data */
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FSSTOREDATA64 = 65538, /* AFS Store file data */
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@ -125,6 +125,9 @@ static void afs_break_callback(struct afs_server *server,
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spin_unlock(&server->cb_lock);
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queue_work(afs_callback_update_worker, &vnode->cb_broken_work);
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if (list_empty(&vnode->granted_locks) &&
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!list_empty(&vnode->pending_locks))
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afs_lock_may_be_available(vnode);
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spin_unlock(&vnode->lock);
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}
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}
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@ -44,6 +44,7 @@ const struct file_operations afs_dir_file_operations = {
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.open = afs_dir_open,
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.release = afs_release,
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.readdir = afs_readdir,
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.lock = afs_lock,
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};
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const struct inode_operations afs_dir_inode_operations = {
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@ -34,6 +34,8 @@ const struct file_operations afs_file_operations = {
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.mmap = generic_file_readonly_mmap,
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.splice_read = generic_file_splice_read,
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.fsync = afs_fsync,
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.lock = afs_lock,
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.flock = afs_flock,
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};
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const struct inode_operations afs_file_inode_operations = {
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@ -0,0 +1,558 @@
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/* AFS file locking support
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*
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* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/smp_lock.h>
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#include "internal.h"
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#define AFS_LOCK_GRANTED 0
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#define AFS_LOCK_PENDING 1
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static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl);
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static void afs_fl_release_private(struct file_lock *fl);
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static struct workqueue_struct *afs_lock_manager;
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static struct file_lock_operations afs_lock_ops = {
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.fl_copy_lock = afs_fl_copy_lock,
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.fl_release_private = afs_fl_release_private,
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};
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/*
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* initialise the lock manager thread if it isn't already running
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*/
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static int afs_init_lock_manager(void)
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{
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if (!afs_lock_manager) {
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afs_lock_manager = create_singlethread_workqueue("kafs_lockd");
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if (!afs_lock_manager)
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return -ENOMEM;
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}
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return 0;
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}
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/*
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* destroy the lock manager thread if it's running
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*/
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void __exit afs_kill_lock_manager(void)
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{
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if (afs_lock_manager)
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destroy_workqueue(afs_lock_manager);
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}
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/*
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* if the callback is broken on this vnode, then the lock may now be available
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*/
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void afs_lock_may_be_available(struct afs_vnode *vnode)
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{
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_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
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queue_delayed_work(afs_lock_manager, &vnode->lock_work, 0);
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}
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/*
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* the lock will time out in 5 minutes unless we extend it, so schedule
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* extension in a bit less than that time
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*/
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static void afs_schedule_lock_extension(struct afs_vnode *vnode)
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{
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queue_delayed_work(afs_lock_manager, &vnode->lock_work,
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AFS_LOCKWAIT * HZ / 2);
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}
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/*
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* do work for a lock, including:
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* - probing for a lock we're waiting on but didn't get immediately
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* - extending a lock that's close to timing out
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*/
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void afs_lock_work(struct work_struct *work)
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{
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struct afs_vnode *vnode =
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container_of(work, struct afs_vnode, lock_work.work);
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struct file_lock *fl;
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afs_lock_type_t type;
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struct key *key;
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int ret;
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_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
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spin_lock(&vnode->lock);
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if (test_bit(AFS_VNODE_UNLOCKING, &vnode->flags)) {
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_debug("unlock");
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spin_unlock(&vnode->lock);
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/* attempt to release the server lock; if it fails, we just
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* wait 5 minutes and it'll time out anyway */
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ret = afs_vnode_release_lock(vnode, vnode->unlock_key);
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if (ret < 0)
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printk(KERN_WARNING "AFS:"
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" Failed to release lock on {%x:%x} error %d\n",
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vnode->fid.vid, vnode->fid.vnode, ret);
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spin_lock(&vnode->lock);
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key_put(vnode->unlock_key);
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vnode->unlock_key = NULL;
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clear_bit(AFS_VNODE_UNLOCKING, &vnode->flags);
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}
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/* if we've got a lock, then it must be time to extend that lock as AFS
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* locks time out after 5 minutes */
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if (!list_empty(&vnode->granted_locks)) {
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_debug("extend");
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if (test_and_set_bit(AFS_VNODE_LOCKING, &vnode->flags))
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BUG();
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fl = list_entry(vnode->granted_locks.next,
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struct file_lock, fl_u.afs.link);
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key = key_get(fl->fl_file->private_data);
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spin_unlock(&vnode->lock);
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ret = afs_vnode_extend_lock(vnode, key);
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clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
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key_put(key);
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switch (ret) {
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case 0:
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afs_schedule_lock_extension(vnode);
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break;
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default:
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/* ummm... we failed to extend the lock - retry
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* extension shortly */
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printk(KERN_WARNING "AFS:"
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" Failed to extend lock on {%x:%x} error %d\n",
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vnode->fid.vid, vnode->fid.vnode, ret);
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queue_delayed_work(afs_lock_manager, &vnode->lock_work,
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HZ * 10);
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break;
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}
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_leave(" [extend]");
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return;
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}
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/* if we don't have a granted lock, then we must've been called back by
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* the server, and so if might be possible to get a lock we're
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* currently waiting for */
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if (!list_empty(&vnode->pending_locks)) {
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_debug("get");
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if (test_and_set_bit(AFS_VNODE_LOCKING, &vnode->flags))
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BUG();
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fl = list_entry(vnode->pending_locks.next,
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struct file_lock, fl_u.afs.link);
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key = key_get(fl->fl_file->private_data);
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type = (fl->fl_type == F_RDLCK) ?
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AFS_LOCK_READ : AFS_LOCK_WRITE;
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spin_unlock(&vnode->lock);
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ret = afs_vnode_set_lock(vnode, key, type);
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clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
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switch (ret) {
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case -EWOULDBLOCK:
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_debug("blocked");
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break;
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case 0:
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_debug("acquired");
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if (type == AFS_LOCK_READ)
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set_bit(AFS_VNODE_READLOCKED, &vnode->flags);
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else
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set_bit(AFS_VNODE_WRITELOCKED, &vnode->flags);
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ret = AFS_LOCK_GRANTED;
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default:
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spin_lock(&vnode->lock);
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/* the pending lock may have been withdrawn due to a
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* signal */
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if (list_entry(vnode->pending_locks.next,
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struct file_lock, fl_u.afs.link) == fl) {
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fl->fl_u.afs.state = ret;
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if (ret == AFS_LOCK_GRANTED)
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list_move_tail(&fl->fl_u.afs.link,
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&vnode->granted_locks);
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else
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list_del_init(&fl->fl_u.afs.link);
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wake_up(&fl->fl_wait);
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spin_unlock(&vnode->lock);
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} else {
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_debug("withdrawn");
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clear_bit(AFS_VNODE_READLOCKED, &vnode->flags);
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clear_bit(AFS_VNODE_WRITELOCKED, &vnode->flags);
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spin_unlock(&vnode->lock);
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afs_vnode_release_lock(vnode, key);
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if (!list_empty(&vnode->pending_locks))
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afs_lock_may_be_available(vnode);
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}
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break;
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}
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key_put(key);
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_leave(" [pend]");
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return;
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}
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/* looks like the lock request was withdrawn on a signal */
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spin_unlock(&vnode->lock);
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_leave(" [no locks]");
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}
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/*
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* pass responsibility for the unlocking of a vnode on the server to the
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* manager thread, lest a pending signal in the calling thread interrupt
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* AF_RXRPC
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* - the caller must hold the vnode lock
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*/
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static void afs_defer_unlock(struct afs_vnode *vnode, struct key *key)
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{
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cancel_delayed_work(&vnode->lock_work);
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if (!test_and_clear_bit(AFS_VNODE_READLOCKED, &vnode->flags) &&
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!test_and_clear_bit(AFS_VNODE_WRITELOCKED, &vnode->flags))
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BUG();
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if (test_and_set_bit(AFS_VNODE_UNLOCKING, &vnode->flags))
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BUG();
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vnode->unlock_key = key_get(key);
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afs_lock_may_be_available(vnode);
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}
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/*
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* request a lock on a file on the server
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*/
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static int afs_do_setlk(struct file *file, struct file_lock *fl)
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{
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struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host);
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afs_lock_type_t type;
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struct key *key = file->private_data;
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int ret;
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_enter("{%x:%u},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
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/* only whole-file locks are supported */
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if (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX)
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return -EINVAL;
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ret = afs_init_lock_manager();
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if (ret < 0)
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return ret;
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fl->fl_ops = &afs_lock_ops;
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INIT_LIST_HEAD(&fl->fl_u.afs.link);
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fl->fl_u.afs.state = AFS_LOCK_PENDING;
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type = (fl->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE;
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lock_kernel();
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/* make sure we've got a callback on this file and that our view of the
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* data version is up to date */
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ret = afs_vnode_fetch_status(vnode, NULL, key);
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if (ret < 0)
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goto error;
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if (vnode->status.lock_count != 0 && !(fl->fl_flags & FL_SLEEP)) {
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ret = -EAGAIN;
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goto error;
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}
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spin_lock(&vnode->lock);
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if (list_empty(&vnode->pending_locks)) {
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/* if there's no-one else with a lock on this vnode, then we
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* need to ask the server for a lock */
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if (list_empty(&vnode->granted_locks)) {
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_debug("not locked");
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ASSERTCMP(vnode->flags &
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((1 << AFS_VNODE_LOCKING) |
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(1 << AFS_VNODE_READLOCKED) |
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(1 << AFS_VNODE_WRITELOCKED)), ==, 0);
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list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks);
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set_bit(AFS_VNODE_LOCKING, &vnode->flags);
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spin_unlock(&vnode->lock);
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ret = afs_vnode_set_lock(vnode, key, type);
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clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
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switch (ret) {
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case 0:
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goto acquired_server_lock;
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case -EWOULDBLOCK:
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spin_lock(&vnode->lock);
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ASSERT(list_empty(&vnode->granted_locks));
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ASSERTCMP(vnode->pending_locks.next, ==,
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&fl->fl_u.afs.link);
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goto wait;
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default:
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spin_lock(&vnode->lock);
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list_del_init(&fl->fl_u.afs.link);
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spin_unlock(&vnode->lock);
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goto error;
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}
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}
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/* if we've already got a readlock on the server and no waiting
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* writelocks, then we might be able to instantly grant another
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* readlock */
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if (type == AFS_LOCK_READ &&
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vnode->flags & (1 << AFS_VNODE_READLOCKED)) {
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_debug("instant readlock");
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ASSERTCMP(vnode->flags &
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((1 << AFS_VNODE_LOCKING) |
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(1 << AFS_VNODE_WRITELOCKED)), ==, 0);
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ASSERT(!list_empty(&vnode->granted_locks));
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goto sharing_existing_lock;
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}
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}
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/* otherwise, we need to wait for a local lock to become available */
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_debug("wait local");
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list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks);
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wait:
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if (!(fl->fl_flags & FL_SLEEP)) {
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_debug("noblock");
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ret = -EAGAIN;
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goto abort_attempt;
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}
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spin_unlock(&vnode->lock);
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/* now we need to sleep and wait for the lock manager thread to get the
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* lock from the server */
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_debug("sleep");
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ret = wait_event_interruptible(fl->fl_wait,
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fl->fl_u.afs.state <= AFS_LOCK_GRANTED);
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if (fl->fl_u.afs.state <= AFS_LOCK_GRANTED) {
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ret = fl->fl_u.afs.state;
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if (ret < 0)
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goto error;
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spin_lock(&vnode->lock);
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goto given_lock;
|
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}
|
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|
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/* we were interrupted, but someone may still be in the throes of
|
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* giving us the lock */
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_debug("intr");
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ASSERTCMP(ret, ==, -ERESTARTSYS);
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spin_lock(&vnode->lock);
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if (fl->fl_u.afs.state <= AFS_LOCK_GRANTED) {
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ret = fl->fl_u.afs.state;
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if (ret < 0) {
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spin_unlock(&vnode->lock);
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goto error;
|
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}
|
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goto given_lock;
|
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}
|
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abort_attempt:
|
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/* we aren't going to get the lock, either because we're unwilling to
|
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* wait, or because some signal happened */
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_debug("abort");
|
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if (list_empty(&vnode->granted_locks) &&
|
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vnode->pending_locks.next == &fl->fl_u.afs.link) {
|
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if (vnode->pending_locks.prev != &fl->fl_u.afs.link) {
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/* kick the next pending lock into having a go */
|
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list_del_init(&fl->fl_u.afs.link);
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afs_lock_may_be_available(vnode);
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}
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} else {
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list_del_init(&fl->fl_u.afs.link);
|
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}
|
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spin_unlock(&vnode->lock);
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goto error;
|
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|
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acquired_server_lock:
|
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/* we've acquired a server lock, but it needs to be renewed after 5
|
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* mins */
|
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spin_lock(&vnode->lock);
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afs_schedule_lock_extension(vnode);
|
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if (type == AFS_LOCK_READ)
|
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set_bit(AFS_VNODE_READLOCKED, &vnode->flags);
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else
|
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set_bit(AFS_VNODE_WRITELOCKED, &vnode->flags);
|
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sharing_existing_lock:
|
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/* the lock has been granted as far as we're concerned... */
|
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fl->fl_u.afs.state = AFS_LOCK_GRANTED;
|
||||
list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks);
|
||||
given_lock:
|
||||
/* ... but we do still need to get the VFS's blessing */
|
||||
ASSERT(!(vnode->flags & (1 << AFS_VNODE_LOCKING)));
|
||||
ASSERT((vnode->flags & ((1 << AFS_VNODE_READLOCKED) |
|
||||
(1 << AFS_VNODE_WRITELOCKED))) != 0);
|
||||
ret = posix_lock_file(file, fl, NULL);
|
||||
if (ret < 0)
|
||||
goto vfs_rejected_lock;
|
||||
spin_unlock(&vnode->lock);
|
||||
|
||||
/* again, make sure we've got a callback on this file and, again, make
|
||||
* sure that our view of the data version is up to date (we ignore
|
||||
* errors incurred here and deal with the consequences elsewhere) */
|
||||
afs_vnode_fetch_status(vnode, NULL, key);
|
||||
|
||||
error:
|
||||
unlock_kernel();
|
||||
_leave(" = %d", ret);
|
||||
return ret;
|
||||
|
||||
vfs_rejected_lock:
|
||||
/* the VFS rejected the lock we just obtained, so we have to discard
|
||||
* what we just got */
|
||||
_debug("vfs refused %d", ret);
|
||||
list_del_init(&fl->fl_u.afs.link);
|
||||
if (list_empty(&vnode->granted_locks))
|
||||
afs_defer_unlock(vnode, key);
|
||||
spin_unlock(&vnode->lock);
|
||||
goto abort_attempt;
|
||||
}
|
||||
|
||||
/*
|
||||
* unlock on a file on the server
|
||||
*/
|
||||
static int afs_do_unlk(struct file *file, struct file_lock *fl)
|
||||
{
|
||||
struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host);
|
||||
struct key *key = file->private_data;
|
||||
int ret;
|
||||
|
||||
_enter("{%x:%u},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
|
||||
|
||||
/* only whole-file unlocks are supported */
|
||||
if (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX)
|
||||
return -EINVAL;
|
||||
|
||||
fl->fl_ops = &afs_lock_ops;
|
||||
INIT_LIST_HEAD(&fl->fl_u.afs.link);
|
||||
fl->fl_u.afs.state = AFS_LOCK_PENDING;
|
||||
|
||||
spin_lock(&vnode->lock);
|
||||
ret = posix_lock_file(file, fl, NULL);
|
||||
if (ret < 0) {
|
||||
spin_unlock(&vnode->lock);
|
||||
_leave(" = %d [vfs]", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* discard the server lock only if all granted locks are gone */
|
||||
if (list_empty(&vnode->granted_locks))
|
||||
afs_defer_unlock(vnode, key);
|
||||
spin_unlock(&vnode->lock);
|
||||
_leave(" = 0");
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* return information about a lock we currently hold, if indeed we hold one
|
||||
*/
|
||||
static int afs_do_getlk(struct file *file, struct file_lock *fl)
|
||||
{
|
||||
struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host);
|
||||
struct key *key = file->private_data;
|
||||
int ret, lock_count;
|
||||
|
||||
_enter("");
|
||||
|
||||
fl->fl_type = F_UNLCK;
|
||||
|
||||
mutex_lock(&vnode->vfs_inode.i_mutex);
|
||||
|
||||
/* check local lock records first */
|
||||
ret = 0;
|
||||
if (posix_test_lock(file, fl) == 0) {
|
||||
/* no local locks; consult the server */
|
||||
ret = afs_vnode_fetch_status(vnode, NULL, key);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
lock_count = vnode->status.lock_count;
|
||||
if (lock_count) {
|
||||
if (lock_count > 0)
|
||||
fl->fl_type = F_RDLCK;
|
||||
else
|
||||
fl->fl_type = F_WRLCK;
|
||||
fl->fl_start = 0;
|
||||
fl->fl_end = OFFSET_MAX;
|
||||
}
|
||||
}
|
||||
|
||||
error:
|
||||
mutex_unlock(&vnode->vfs_inode.i_mutex);
|
||||
_leave(" = %d [%hd]", ret, fl->fl_type);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* manage POSIX locks on a file
|
||||
*/
|
||||
int afs_lock(struct file *file, int cmd, struct file_lock *fl)
|
||||
{
|
||||
struct afs_vnode *vnode = AFS_FS_I(file->f_dentry->d_inode);
|
||||
|
||||
_enter("{%x:%u},%d,{t=%x,fl=%x,r=%Ld:%Ld}",
|
||||
vnode->fid.vid, vnode->fid.vnode, cmd,
|
||||
fl->fl_type, fl->fl_flags,
|
||||
(long long) fl->fl_start, (long long) fl->fl_end);
|
||||
|
||||
/* AFS doesn't support mandatory locks */
|
||||
if ((vnode->vfs_inode.i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
|
||||
fl->fl_type != F_UNLCK)
|
||||
return -ENOLCK;
|
||||
|
||||
if (IS_GETLK(cmd))
|
||||
return afs_do_getlk(file, fl);
|
||||
if (fl->fl_type == F_UNLCK)
|
||||
return afs_do_unlk(file, fl);
|
||||
return afs_do_setlk(file, fl);
|
||||
}
|
||||
|
||||
/*
|
||||
* manage FLOCK locks on a file
|
||||
*/
|
||||
int afs_flock(struct file *file, int cmd, struct file_lock *fl)
|
||||
{
|
||||
struct afs_vnode *vnode = AFS_FS_I(file->f_dentry->d_inode);
|
||||
|
||||
_enter("{%x:%u},%d,{t=%x,fl=%x}",
|
||||
vnode->fid.vid, vnode->fid.vnode, cmd,
|
||||
fl->fl_type, fl->fl_flags);
|
||||
|
||||
/*
|
||||
* No BSD flocks over NFS allowed.
|
||||
* Note: we could try to fake a POSIX lock request here by
|
||||
* using ((u32) filp | 0x80000000) or some such as the pid.
|
||||
* Not sure whether that would be unique, though, or whether
|
||||
* that would break in other places.
|
||||
*/
|
||||
if (!(fl->fl_flags & FL_FLOCK))
|
||||
return -ENOLCK;
|
||||
|
||||
/* we're simulating flock() locks using posix locks on the server */
|
||||
fl->fl_owner = (fl_owner_t) file;
|
||||
fl->fl_start = 0;
|
||||
fl->fl_end = OFFSET_MAX;
|
||||
|
||||
if (fl->fl_type == F_UNLCK)
|
||||
return afs_do_unlk(file, fl);
|
||||
return afs_do_setlk(file, fl);
|
||||
}
|
||||
|
||||
/*
|
||||
* the POSIX lock management core VFS code copies the lock record and adds the
|
||||
* copy into its own list, so we need to add that copy to the vnode's lock
|
||||
* queue in the same place as the original (which will be deleted shortly
|
||||
* after)
|
||||
*/
|
||||
static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl)
|
||||
{
|
||||
_enter("");
|
||||
|
||||
list_add(&new->fl_u.afs.link, &fl->fl_u.afs.link);
|
||||
}
|
||||
|
||||
/*
|
||||
* need to remove this lock from the vnode queue when it's removed from the
|
||||
* VFS's list
|
||||
*/
|
||||
static void afs_fl_release_private(struct file_lock *fl)
|
||||
{
|
||||
_enter("");
|
||||
|
||||
list_del_init(&fl->fl_u.afs.link);
|
||||
}
|
|
@ -67,7 +67,7 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
|
|||
EXTRACT(status->group);
|
||||
bp++; /* sync counter */
|
||||
data_version |= (u64) ntohl(*bp++) << 32;
|
||||
bp++; /* lock count */
|
||||
EXTRACT(status->lock_count);
|
||||
size |= (u64) ntohl(*bp++) << 32;
|
||||
bp++; /* spare 4 */
|
||||
*_bp = bp;
|
||||
|
@ -1748,3 +1748,156 @@ int afs_fs_get_volume_status(struct afs_server *server,
|
|||
|
||||
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
|
||||
}
|
||||
|
||||
/*
|
||||
* deliver reply data to an FS.SetLock, FS.ExtendLock or FS.ReleaseLock
|
||||
*/
|
||||
static int afs_deliver_fs_xxxx_lock(struct afs_call *call,
|
||||
struct sk_buff *skb, bool last)
|
||||
{
|
||||
const __be32 *bp;
|
||||
|
||||
_enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
|
||||
|
||||
afs_transfer_reply(call, skb);
|
||||
if (!last)
|
||||
return 0;
|
||||
|
||||
if (call->reply_size != call->reply_max)
|
||||
return -EBADMSG;
|
||||
|
||||
/* unmarshall the reply once we've received all of it */
|
||||
bp = call->buffer;
|
||||
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
|
||||
|
||||
_leave(" = 0 [done]");
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* FS.SetLock operation type
|
||||
*/
|
||||
static const struct afs_call_type afs_RXFSSetLock = {
|
||||
.name = "FS.SetLock",
|
||||
.deliver = afs_deliver_fs_xxxx_lock,
|
||||
.abort_to_error = afs_abort_to_error,
|
||||
.destructor = afs_flat_call_destructor,
|
||||
};
|
||||
|
||||
/*
|
||||
* FS.ExtendLock operation type
|
||||
*/
|
||||
static const struct afs_call_type afs_RXFSExtendLock = {
|
||||
.name = "FS.ExtendLock",
|
||||
.deliver = afs_deliver_fs_xxxx_lock,
|
||||
.abort_to_error = afs_abort_to_error,
|
||||
.destructor = afs_flat_call_destructor,
|
||||
};
|
||||
|
||||
/*
|
||||
* FS.ReleaseLock operation type
|
||||
*/
|
||||
static const struct afs_call_type afs_RXFSReleaseLock = {
|
||||
.name = "FS.ReleaseLock",
|
||||
.deliver = afs_deliver_fs_xxxx_lock,
|
||||
.abort_to_error = afs_abort_to_error,
|
||||
.destructor = afs_flat_call_destructor,
|
||||
};
|
||||
|
||||
/*
|
||||
* get a lock on a file
|
||||
*/
|
||||
int afs_fs_set_lock(struct afs_server *server,
|
||||
struct key *key,
|
||||
struct afs_vnode *vnode,
|
||||
afs_lock_type_t type,
|
||||
const struct afs_wait_mode *wait_mode)
|
||||
{
|
||||
struct afs_call *call;
|
||||
__be32 *bp;
|
||||
|
||||
_enter("");
|
||||
|
||||
call = afs_alloc_flat_call(&afs_RXFSSetLock, 5 * 4, 6 * 4);
|
||||
if (!call)
|
||||
return -ENOMEM;
|
||||
|
||||
call->key = key;
|
||||
call->reply = vnode;
|
||||
call->service_id = FS_SERVICE;
|
||||
call->port = htons(AFS_FS_PORT);
|
||||
|
||||
/* marshall the parameters */
|
||||
bp = call->request;
|
||||
*bp++ = htonl(FSSETLOCK);
|
||||
*bp++ = htonl(vnode->fid.vid);
|
||||
*bp++ = htonl(vnode->fid.vnode);
|
||||
*bp++ = htonl(vnode->fid.unique);
|
||||
*bp++ = htonl(type);
|
||||
|
||||
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
|
||||
}
|
||||
|
||||
/*
|
||||
* extend a lock on a file
|
||||
*/
|
||||
int afs_fs_extend_lock(struct afs_server *server,
|
||||
struct key *key,
|
||||
struct afs_vnode *vnode,
|
||||
const struct afs_wait_mode *wait_mode)
|
||||
{
|
||||
struct afs_call *call;
|
||||
__be32 *bp;
|
||||
|
||||
_enter("");
|
||||
|
||||
call = afs_alloc_flat_call(&afs_RXFSExtendLock, 4 * 4, 6 * 4);
|
||||
if (!call)
|
||||
return -ENOMEM;
|
||||
|
||||
call->key = key;
|
||||
call->reply = vnode;
|
||||
call->service_id = FS_SERVICE;
|
||||
call->port = htons(AFS_FS_PORT);
|
||||
|
||||
/* marshall the parameters */
|
||||
bp = call->request;
|
||||
*bp++ = htonl(FSEXTENDLOCK);
|
||||
*bp++ = htonl(vnode->fid.vid);
|
||||
*bp++ = htonl(vnode->fid.vnode);
|
||||
*bp++ = htonl(vnode->fid.unique);
|
||||
|
||||
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
|
||||
}
|
||||
|
||||
/*
|
||||
* release a lock on a file
|
||||
*/
|
||||
int afs_fs_release_lock(struct afs_server *server,
|
||||
struct key *key,
|
||||
struct afs_vnode *vnode,
|
||||
const struct afs_wait_mode *wait_mode)
|
||||
{
|
||||
struct afs_call *call;
|
||||
__be32 *bp;
|
||||
|
||||
_enter("");
|
||||
|
||||
call = afs_alloc_flat_call(&afs_RXFSReleaseLock, 4 * 4, 6 * 4);
|
||||
if (!call)
|
||||
return -ENOMEM;
|
||||
|
||||
call->key = key;
|
||||
call->reply = vnode;
|
||||
call->service_id = FS_SERVICE;
|
||||
call->port = htons(AFS_FS_PORT);
|
||||
|
||||
/* marshall the parameters */
|
||||
bp = call->request;
|
||||
*bp++ = htonl(FSRELEASELOCK);
|
||||
*bp++ = htonl(vnode->fid.vid);
|
||||
*bp++ = htonl(vnode->fid.vnode);
|
||||
*bp++ = htonl(vnode->fid.unique);
|
||||
|
||||
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
|
||||
}
|
||||
|
|
|
@ -351,10 +351,18 @@ struct afs_vnode {
|
|||
#define AFS_VNODE_ZAP_DATA 3 /* set if vnode's data should be invalidated */
|
||||
#define AFS_VNODE_DELETED 4 /* set if vnode deleted on server */
|
||||
#define AFS_VNODE_MOUNTPOINT 5 /* set if vnode is a mountpoint symlink */
|
||||
#define AFS_VNODE_LOCKING 6 /* set if waiting for lock on vnode */
|
||||
#define AFS_VNODE_READLOCKED 7 /* set if vnode is read-locked on the server */
|
||||
#define AFS_VNODE_WRITELOCKED 8 /* set if vnode is write-locked on the server */
|
||||
#define AFS_VNODE_UNLOCKING 9 /* set if vnode is being unlocked on the server */
|
||||
|
||||
long acl_order; /* ACL check count (callback break count) */
|
||||
|
||||
struct list_head writebacks; /* alterations in pagecache that need writing */
|
||||
struct list_head pending_locks; /* locks waiting to be granted */
|
||||
struct list_head granted_locks; /* locks granted on this file */
|
||||
struct delayed_work lock_work; /* work to be done in locking */
|
||||
struct key *unlock_key; /* key to be used in unlocking */
|
||||
|
||||
/* outstanding callback notification on this file */
|
||||
struct rb_node server_rb; /* link in server->fs_vnodes */
|
||||
|
@ -473,6 +481,15 @@ extern const struct file_operations afs_file_operations;
|
|||
extern int afs_open(struct inode *, struct file *);
|
||||
extern int afs_release(struct inode *, struct file *);
|
||||
|
||||
/*
|
||||
* flock.c
|
||||
*/
|
||||
extern void __exit afs_kill_lock_manager(void);
|
||||
extern void afs_lock_work(struct work_struct *);
|
||||
extern void afs_lock_may_be_available(struct afs_vnode *);
|
||||
extern int afs_lock(struct file *, int, struct file_lock *);
|
||||
extern int afs_flock(struct file *, int, struct file_lock *);
|
||||
|
||||
/*
|
||||
* fsclient.c
|
||||
*/
|
||||
|
@ -513,6 +530,15 @@ extern int afs_fs_get_volume_status(struct afs_server *, struct key *,
|
|||
struct afs_vnode *,
|
||||
struct afs_volume_status *,
|
||||
const struct afs_wait_mode *);
|
||||
extern int afs_fs_set_lock(struct afs_server *, struct key *,
|
||||
struct afs_vnode *, afs_lock_type_t,
|
||||
const struct afs_wait_mode *);
|
||||
extern int afs_fs_extend_lock(struct afs_server *, struct key *,
|
||||
struct afs_vnode *,
|
||||
const struct afs_wait_mode *);
|
||||
extern int afs_fs_release_lock(struct afs_server *, struct key *,
|
||||
struct afs_vnode *,
|
||||
const struct afs_wait_mode *);
|
||||
|
||||
/*
|
||||
* inode.c
|
||||
|
@ -681,6 +707,10 @@ extern int afs_vnode_store_data(struct afs_writeback *, pgoff_t, pgoff_t,
|
|||
extern int afs_vnode_setattr(struct afs_vnode *, struct key *, struct iattr *);
|
||||
extern int afs_vnode_get_volume_status(struct afs_vnode *, struct key *,
|
||||
struct afs_volume_status *);
|
||||
extern int afs_vnode_set_lock(struct afs_vnode *, struct key *,
|
||||
afs_lock_type_t);
|
||||
extern int afs_vnode_extend_lock(struct afs_vnode *, struct key *);
|
||||
extern int afs_vnode_release_lock(struct afs_vnode *, struct key *);
|
||||
|
||||
/*
|
||||
* volume.c
|
||||
|
|
|
@ -168,6 +168,7 @@ static void __exit afs_exit(void)
|
|||
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 unregistering.\n");
|
||||
|
||||
afs_fs_exit();
|
||||
afs_kill_lock_manager();
|
||||
afs_close_socket();
|
||||
afs_purge_servers();
|
||||
afs_callback_update_kill();
|
||||
|
|
|
@ -35,6 +35,7 @@ int afs_abort_to_error(u32 abort_code)
|
|||
case VOVERQUOTA: return -EDQUOT;
|
||||
case VBUSY: return -EBUSY;
|
||||
case VMOVED: return -ENXIO;
|
||||
case 0x2f6df0a: return -EWOULDBLOCK;
|
||||
case 0x2f6df0c: return -EACCES;
|
||||
case 0x2f6df0f: return -EBUSY;
|
||||
case 0x2f6df10: return -EEXIST;
|
||||
|
|
|
@ -460,6 +460,9 @@ static void afs_i_init_once(void *_vnode, struct kmem_cache *cachep,
|
|||
spin_lock_init(&vnode->writeback_lock);
|
||||
spin_lock_init(&vnode->lock);
|
||||
INIT_LIST_HEAD(&vnode->writebacks);
|
||||
INIT_LIST_HEAD(&vnode->pending_locks);
|
||||
INIT_LIST_HEAD(&vnode->granted_locks);
|
||||
INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
|
||||
INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
|
||||
}
|
||||
|
||||
|
|
130
fs/afs/vnode.c
130
fs/afs/vnode.c
|
@ -887,11 +887,6 @@ int afs_vnode_get_volume_status(struct afs_vnode *vnode, struct key *key,
|
|||
vnode->fid.unique,
|
||||
key_serial(key));
|
||||
|
||||
/* this op will fetch the status */
|
||||
spin_lock(&vnode->lock);
|
||||
vnode->update_cnt++;
|
||||
spin_unlock(&vnode->lock);
|
||||
|
||||
do {
|
||||
/* pick a server to query */
|
||||
server = afs_volume_pick_fileserver(vnode);
|
||||
|
@ -905,20 +900,127 @@ int afs_vnode_get_volume_status(struct afs_vnode *vnode, struct key *key,
|
|||
} while (!afs_volume_release_fileserver(vnode, server, ret));
|
||||
|
||||
/* adjust the flags */
|
||||
if (ret == 0) {
|
||||
afs_vnode_finalise_status_update(vnode, server);
|
||||
if (ret == 0)
|
||||
afs_put_server(server);
|
||||
|
||||
_leave(" = %d", ret);
|
||||
return ret;
|
||||
|
||||
no_server:
|
||||
return PTR_ERR(server);
|
||||
}
|
||||
|
||||
/*
|
||||
* get a lock on a file
|
||||
*/
|
||||
int afs_vnode_set_lock(struct afs_vnode *vnode, struct key *key,
|
||||
afs_lock_type_t type)
|
||||
{
|
||||
struct afs_server *server;
|
||||
int ret;
|
||||
|
||||
_enter("%s{%x:%u.%u},%x,%u",
|
||||
vnode->volume->vlocation->vldb.name,
|
||||
vnode->fid.vid,
|
||||
vnode->fid.vnode,
|
||||
vnode->fid.unique,
|
||||
key_serial(key), type);
|
||||
|
||||
do {
|
||||
/* pick a server to query */
|
||||
server = afs_volume_pick_fileserver(vnode);
|
||||
if (IS_ERR(server))
|
||||
goto no_server;
|
||||
|
||||
_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
|
||||
|
||||
ret = afs_fs_set_lock(server, key, vnode, type, &afs_sync_call);
|
||||
|
||||
} while (!afs_volume_release_fileserver(vnode, server, ret));
|
||||
|
||||
/* adjust the flags */
|
||||
if (ret == 0)
|
||||
afs_put_server(server);
|
||||
|
||||
_leave(" = %d", ret);
|
||||
return ret;
|
||||
|
||||
no_server:
|
||||
return PTR_ERR(server);
|
||||
}
|
||||
|
||||
/*
|
||||
* extend a lock on a file
|
||||
*/
|
||||
int afs_vnode_extend_lock(struct afs_vnode *vnode, struct key *key)
|
||||
{
|
||||
struct afs_server *server;
|
||||
int ret;
|
||||
|
||||
_enter("%s{%x:%u.%u},%x",
|
||||
vnode->volume->vlocation->vldb.name,
|
||||
vnode->fid.vid,
|
||||
vnode->fid.vnode,
|
||||
vnode->fid.unique,
|
||||
key_serial(key));
|
||||
|
||||
do {
|
||||
/* pick a server to query */
|
||||
server = afs_volume_pick_fileserver(vnode);
|
||||
if (IS_ERR(server))
|
||||
goto no_server;
|
||||
|
||||
_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
|
||||
|
||||
ret = afs_fs_extend_lock(server, key, vnode, &afs_sync_call);
|
||||
|
||||
} while (!afs_volume_release_fileserver(vnode, server, ret));
|
||||
|
||||
/* adjust the flags */
|
||||
if (ret == 0)
|
||||
afs_put_server(server);
|
||||
|
||||
_leave(" = %d", ret);
|
||||
return ret;
|
||||
|
||||
no_server:
|
||||
return PTR_ERR(server);
|
||||
}
|
||||
|
||||
/*
|
||||
* release a lock on a file
|
||||
*/
|
||||
int afs_vnode_release_lock(struct afs_vnode *vnode, struct key *key)
|
||||
{
|
||||
struct afs_server *server;
|
||||
int ret;
|
||||
|
||||
_enter("%s{%x:%u.%u},%x",
|
||||
vnode->volume->vlocation->vldb.name,
|
||||
vnode->fid.vid,
|
||||
vnode->fid.vnode,
|
||||
vnode->fid.unique,
|
||||
key_serial(key));
|
||||
|
||||
do {
|
||||
/* pick a server to query */
|
||||
server = afs_volume_pick_fileserver(vnode);
|
||||
if (IS_ERR(server))
|
||||
goto no_server;
|
||||
|
||||
_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
|
||||
|
||||
ret = afs_fs_release_lock(server, key, vnode, &afs_sync_call);
|
||||
|
||||
} while (!afs_volume_release_fileserver(vnode, server, ret));
|
||||
|
||||
/* adjust the flags */
|
||||
if (ret == 0)
|
||||
afs_put_server(server);
|
||||
} else {
|
||||
afs_vnode_status_update_failed(vnode, ret);
|
||||
}
|
||||
|
||||
_leave(" = %d", ret);
|
||||
return ret;
|
||||
|
||||
no_server:
|
||||
spin_lock(&vnode->lock);
|
||||
vnode->update_cnt--;
|
||||
ASSERTCMP(vnode->update_cnt, >=, 0);
|
||||
spin_unlock(&vnode->lock);
|
||||
return PTR_ERR(server);
|
||||
}
|
||||
|
|
|
@ -820,6 +820,10 @@ struct file_lock {
|
|||
union {
|
||||
struct nfs_lock_info nfs_fl;
|
||||
struct nfs4_lock_info nfs4_fl;
|
||||
struct {
|
||||
struct list_head link; /* link in AFS vnode's pending_locks list */
|
||||
int state; /* state of grant or error if -ve */
|
||||
} afs;
|
||||
} fl_u;
|
||||
};
|
||||
|
||||
|
|
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