X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fautofs4%2Fwaitq.c;h=1e4a539f4417c3c94a38c844c6a419dea606d709;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=394ff36ef8f19ec84a4f26a0c1a96e2badb7cb84;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 394ff36ef..1e4a539f4 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -3,7 +3,7 @@ * linux/fs/autofs/waitq.c * * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved - * Copyright 2001-2003 Ian Kent + * Copyright 2001-2006 Ian Kent * * This file is part of the Linux kernel and is made available under * the terms of the GNU General Public License, version 2, or at your @@ -33,7 +33,7 @@ void autofs4_catatonic_mode(struct autofs_sb_info *sbi) sbi->catatonic = 1; wq = sbi->queues; sbi->queues = NULL; /* Erase all wait queues */ - while ( wq ) { + while (wq) { nwq = wq->next; wq->status = -ENOENT; /* Magic is gone - report failure */ kfree(wq->name); @@ -41,12 +41,8 @@ void autofs4_catatonic_mode(struct autofs_sb_info *sbi) wake_up_interruptible(&wq->queue); wq = nwq; } - if (sbi->pipe) { - fput(sbi->pipe); /* Close the pipe */ - sbi->pipe = NULL; - } - - shrink_dcache_sb(sbi->sb); + fput(sbi->pipe); /* Close the pipe */ + sbi->pipe = NULL; } static int autofs4_write(struct file *file, const void *addr, int bytes) @@ -98,7 +94,10 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi, pkt.hdr.proto_version = sbi->version; pkt.hdr.type = type; - if (type == autofs_ptype_missing) { + switch (type) { + /* Kernel protocol v4 missing and expire packets */ + case autofs_ptype_missing: + { struct autofs_packet_missing *mp = &pkt.missing; pktsz = sizeof(*mp); @@ -107,7 +106,10 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi, mp->len = wq->len; memcpy(mp->name, wq->name, wq->len); mp->name[wq->len] = '\0'; - } else if (type == autofs_ptype_expire_multi) { + break; + } + case autofs_ptype_expire_multi: + { struct autofs_packet_expire_multi *ep = &pkt.expire_multi; pktsz = sizeof(*ep); @@ -116,7 +118,34 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi, ep->len = wq->len; memcpy(ep->name, wq->name, wq->len); ep->name[wq->len] = '\0'; - } else { + break; + } + /* + * Kernel protocol v5 packet for handling indirect and direct + * mount missing and expire requests + */ + case autofs_ptype_missing_indirect: + case autofs_ptype_expire_indirect: + case autofs_ptype_missing_direct: + case autofs_ptype_expire_direct: + { + struct autofs_v5_packet *packet = &pkt.v5_packet; + + pktsz = sizeof(*packet); + + packet->wait_queue_token = wq->wait_queue_token; + packet->len = wq->len; + memcpy(packet->name, wq->name, wq->len); + packet->name[wq->len] = '\0'; + packet->dev = wq->dev; + packet->ino = wq->ino; + packet->uid = wq->uid; + packet->gid = wq->gid; + packet->pid = wq->pid; + packet->tgid = wq->tgid; + break; + } + default: printk("autofs4_notify_daemon: bad type %d!\n", type); return; } @@ -157,52 +186,96 @@ static int autofs4_getpath(struct autofs_sb_info *sbi, return len; } +static struct autofs_wait_queue * +autofs4_find_wait(struct autofs_sb_info *sbi, + char *name, unsigned int hash, unsigned int len) +{ + struct autofs_wait_queue *wq; + + for (wq = sbi->queues; wq; wq = wq->next) { + if (wq->hash == hash && + wq->len == len && + wq->name && !memcmp(wq->name, name, len)) + break; + } + return wq; +} + int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, enum autofs_notify notify) { + struct autofs_info *ino; struct autofs_wait_queue *wq; char *name; - int len, status; + unsigned int len = 0; + unsigned int hash = 0; + int status, type; /* In catatonic mode, we don't wait for nobody */ - if ( sbi->catatonic ) + if (sbi->catatonic) return -ENOENT; name = kmalloc(NAME_MAX + 1, GFP_KERNEL); if (!name) return -ENOMEM; - len = autofs4_getpath(sbi, dentry, &name); - if (!len) { - kfree(name); - return -ENOENT; + /* If this is a direct mount request create a dummy name */ + if (IS_ROOT(dentry) && (sbi->type & AUTOFS_TYPE_DIRECT)) + len = sprintf(name, "%p", dentry); + else { + len = autofs4_getpath(sbi, dentry, &name); + if (!len) { + kfree(name); + return -ENOENT; + } } + hash = full_name_hash(name, len); - if (down_interruptible(&sbi->wq_sem)) { + if (mutex_lock_interruptible(&sbi->wq_mutex)) { kfree(name); return -EINTR; } - for (wq = sbi->queues ; wq ; wq = wq->next) { - if (wq->hash == dentry->d_name.hash && - wq->len == len && - wq->name && !memcmp(wq->name, name, len)) - break; - } + wq = autofs4_find_wait(sbi, name, hash, len); + ino = autofs4_dentry_ino(dentry); + if (!wq && ino && notify == NFY_NONE) { + /* + * Either we've betean the pending expire to post it's + * wait or it finished while we waited on the mutex. + * So we need to wait till either, the wait appears + * or the expire finishes. + */ + + while (ino->flags & AUTOFS_INF_EXPIRING) { + mutex_unlock(&sbi->wq_mutex); + schedule_timeout_interruptible(HZ/10); + if (mutex_lock_interruptible(&sbi->wq_mutex)) { + kfree(name); + return -EINTR; + } + wq = autofs4_find_wait(sbi, name, hash, len); + if (wq) + break; + } - if ( !wq ) { - /* Can't wait for an expire if there's no mount */ - if (notify == NFY_NONE && !d_mountpoint(dentry)) { + /* + * Not ideal but the status has already gone. Of the two + * cases where we wait on NFY_NONE neither depend on the + * return status of the wait. + */ + if (!wq) { kfree(name); - up(&sbi->wq_sem); - return -ENOENT; + mutex_unlock(&sbi->wq_mutex); + return 0; } + } + if (!wq) { /* Create a new wait queue */ wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL); - if ( !wq ) { + if (!wq) { kfree(name); - up(&sbi->wq_sem); + mutex_unlock(&sbi->wq_mutex); return -ENOMEM; } @@ -212,42 +285,58 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, wq->next = sbi->queues; sbi->queues = wq; init_waitqueue_head(&wq->queue); - wq->hash = dentry->d_name.hash; + wq->hash = hash; wq->name = name; wq->len = len; + wq->dev = autofs4_get_dev(sbi); + wq->ino = autofs4_get_ino(sbi); + wq->uid = current->uid; + wq->gid = current->gid; + wq->pid = current->pid; + wq->tgid = current->tgid; wq->status = -EINTR; /* Status return if interrupted */ atomic_set(&wq->wait_ctr, 2); - atomic_set(&wq->notified, 1); - up(&sbi->wq_sem); - } else { - atomic_inc(&wq->wait_ctr); - up(&sbi->wq_sem); - kfree(name); - DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d", - (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify); - } - - if (notify != NFY_NONE && atomic_dec_and_test(&wq->notified)) { - int type = (notify == NFY_MOUNT ? - autofs_ptype_missing : autofs_ptype_expire_multi); + mutex_unlock(&sbi->wq_mutex); + + if (sbi->version < 5) { + if (notify == NFY_MOUNT) + type = autofs_ptype_missing; + else + type = autofs_ptype_expire_multi; + } else { + if (notify == NFY_MOUNT) + type = (sbi->type & AUTOFS_TYPE_DIRECT) ? + autofs_ptype_missing_direct : + autofs_ptype_missing_indirect; + else + type = (sbi->type & AUTOFS_TYPE_DIRECT) ? + autofs_ptype_expire_direct : + autofs_ptype_expire_indirect; + } DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n", (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify); /* autofs4_notify_daemon() may block */ autofs4_notify_daemon(sbi, wq, type); + } else { + atomic_inc(&wq->wait_ctr); + mutex_unlock(&sbi->wq_mutex); + kfree(name); + DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d", + (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify); } /* wq->name is NULL if and only if the lock is already released */ - if ( sbi->catatonic ) { + if (sbi->catatonic) { /* We might have slept, so check again for catatonic mode */ wq->status = -ENOENT; kfree(wq->name); wq->name = NULL; } - if ( wq->name ) { + if (wq->name) { /* Block all but "shutdown" signals while waiting */ sigset_t oldset; unsigned long irqflags; @@ -282,19 +371,19 @@ int autofs4_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_tok { struct autofs_wait_queue *wq, **wql; - down(&sbi->wq_sem); - for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) { - if ( wq->wait_queue_token == wait_queue_token ) + mutex_lock(&sbi->wq_mutex); + for (wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next) { + if (wq->wait_queue_token == wait_queue_token) break; } - if ( !wq ) { - up(&sbi->wq_sem); + if (!wq) { + mutex_unlock(&sbi->wq_mutex); return -EINVAL; } *wql = wq->next; /* Unlink from chain */ - up(&sbi->wq_sem); + mutex_unlock(&sbi->wq_mutex); kfree(wq->name); wq->name = NULL; /* Do not wait on this queue */