x86: reserve_early end-of-conventional-memory to 1MB, 64-bit
[safe/jmp/linux-2.6] / fs / autofs4 / waitq.c
index b0bb9d4..1fe28e4 100644 (file)
@@ -3,7 +3,7 @@
  * linux/fs/autofs/waitq.c
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
- *  Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ *  Copyright 2001-2006 Ian Kent <raven@themaw.net>
  *
  * 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
@@ -41,11 +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)
@@ -87,7 +84,11 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
                                 struct autofs_wait_queue *wq,
                                 int type)
 {
-       union autofs_packet_union pkt;
+       union {
+               struct autofs_packet_hdr hdr;
+               union autofs_packet_union v4_pkt;
+               union autofs_v5_packet_union v5_pkt;
+       } pkt;
        size_t pktsz;
 
        DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d",
@@ -97,8 +98,11 @@ 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) {
-               struct autofs_packet_missing *mp = &pkt.missing;
+       switch (type) {
+       /* Kernel protocol v4 missing and expire packets */
+       case autofs_ptype_missing:
+       {
+               struct autofs_packet_missing *mp = &pkt.v4_pkt.missing;
 
                pktsz = sizeof(*mp);
 
@@ -106,8 +110,11 @@ 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) {
-               struct autofs_packet_expire_multi *ep = &pkt.expire_multi;
+               break;
+       }
+       case autofs_ptype_expire_multi:
+       {
+               struct autofs_packet_expire_multi *ep = &pkt.v4_pkt.expire_multi;
 
                pktsz = sizeof(*ep);
 
@@ -115,7 +122,34 @@ 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_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;
        }
@@ -156,12 +190,30 @@ 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)
@@ -171,32 +223,58 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
        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 (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);
                        mutex_unlock(&sbi->wq_mutex);
-                       return -ENOENT;
+                       return 0;
                }
+       }
 
+       if (!wq) {
                /* Create a new wait queue */
                wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
                if (!wq) {
@@ -211,30 +289,46 @@ 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);
-               mutex_unlock(&sbi->wq_mutex);
-       } 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);
-       }
 
-       if (notify != NFY_NONE && atomic_dec_and_test(&wq->notified)) {
-               int type = (notify == NFY_MOUNT ?
-                       autofs_ptype_missing : autofs_ptype_expire_multi);
+               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 */
@@ -282,7 +376,7 @@ int autofs4_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_tok
        struct autofs_wait_queue *wq, **wql;
 
        mutex_lock(&sbi->wq_mutex);
-       for (wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next) {
+       for (wql = &sbi->queues; (wq = *wql) != NULL; wql = &wq->next) {
                if (wq->wait_queue_token == wait_queue_token)
                        break;
        }