Index: linux-2.6.13/fs/autofs4/root.c =================================================================== --- linux-2.6.13/fs/autofs4/root.c +++ linux-2.6.13/fs/autofs4/root.c @@ -4,7 +4,7 @@ * * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved * Copyright 1999-2000 Jeremy Fitzhardinge - * 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 @@ -25,28 +25,28 @@ static int autofs4_dir_rmdir(struct inod static int autofs4_dir_mkdir(struct inode *,struct dentry *,int); static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long); static int autofs4_dir_open(struct inode *inode, struct file *file); -static int autofs4_dir_close(struct inode *inode, struct file *file); -static int autofs4_dir_readdir(struct file * filp, void * dirent, filldir_t filldir); -static int autofs4_root_readdir(struct file * filp, void * dirent, filldir_t filldir); static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *); -static int autofs4_dcache_readdir(struct file *, void *, filldir_t); +static void *autofs4_follow_link(struct dentry *, struct nameidata *); + +#define TRIGGER_FLAGS (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) +#define TRIGGER_INTENTS (LOOKUP_OPEN | LOOKUP_CREATE) struct file_operations autofs4_root_operations = { .open = dcache_dir_open, .release = dcache_dir_close, .read = generic_read_dir, - .readdir = autofs4_root_readdir, + .readdir = dcache_readdir, .ioctl = autofs4_root_ioctl, }; struct file_operations autofs4_dir_operations = { .open = autofs4_dir_open, - .release = autofs4_dir_close, + .release = dcache_dir_close, .read = generic_read_dir, - .readdir = autofs4_dir_readdir, + .readdir = dcache_readdir, }; -struct inode_operations autofs4_root_inode_operations = { +struct inode_operations autofs4_indirect_root_inode_operations = { .lookup = autofs4_lookup, .unlink = autofs4_dir_unlink, .symlink = autofs4_dir_symlink, @@ -54,6 +54,14 @@ struct inode_operations autofs4_root_ino .rmdir = autofs4_dir_rmdir, }; +struct inode_operations autofs4_direct_root_inode_operations = { + .lookup = autofs4_lookup, + .unlink = autofs4_dir_unlink, + .mkdir = autofs4_dir_mkdir, + .rmdir = autofs4_dir_rmdir, + .follow_link = autofs4_follow_link, +}; + struct inode_operations autofs4_dir_inode_operations = { .lookup = autofs4_lookup, .unlink = autofs4_dir_unlink, @@ -62,113 +70,10 @@ struct inode_operations autofs4_dir_inod .rmdir = autofs4_dir_rmdir, }; -static int autofs4_root_readdir(struct file *file, void *dirent, - filldir_t filldir) -{ - struct autofs_sb_info *sbi = autofs4_sbi(file->f_dentry->d_sb); - int oz_mode = autofs4_oz_mode(sbi); - - DPRINTK("called, filp->f_pos = %lld", file->f_pos); - - /* - * Don't set reghost flag if: - * 1) f_pos is larger than zero -- we've already been here. - * 2) we haven't even enabled reghosting in the 1st place. - * 3) this is the daemon doing a readdir - */ - if (oz_mode && file->f_pos == 0 && sbi->reghost_enabled) - sbi->needs_reghost = 1; - - DPRINTK("needs_reghost = %d", sbi->needs_reghost); - - return autofs4_dcache_readdir(file, dirent, filldir); -} - -/* Update usage from here to top of tree, so that scan of - top-level directories will give a useful result */ -static void autofs4_update_usage(struct dentry *dentry) -{ - struct dentry *top = dentry->d_sb->s_root; - - spin_lock(&dcache_lock); - for(; dentry != top; dentry = dentry->d_parent) { - struct autofs_info *ino = autofs4_dentry_ino(dentry); - - if (ino) { - update_atime(dentry->d_inode); - ino->last_used = jiffies; - } - } - spin_unlock(&dcache_lock); -} - -/* - * From 2.4 kernel readdir.c - */ -static int autofs4_dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) -{ - int i; - struct dentry *dentry = filp->f_dentry; - - i = filp->f_pos; - switch (i) { - case 0: - if (filldir(dirent, ".", 1, i, dentry->d_inode->i_ino, DT_DIR) < 0) - break; - i++; - filp->f_pos++; - /* fallthrough */ - case 1: - if (filldir(dirent, "..", 2, i, dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) - break; - i++; - filp->f_pos++; - /* fallthrough */ - default: { - struct list_head *list; - int j = i-2; - - spin_lock(&dcache_lock); - list = dentry->d_subdirs.next; - - for (;;) { - if (list == &dentry->d_subdirs) { - spin_unlock(&dcache_lock); - return 0; - } - if (!j) - break; - j--; - list = list->next; - } - - while(1) { - struct dentry *de = list_entry(list, struct dentry, d_child); - - if (!d_unhashed(de) && de->d_inode) { - spin_unlock(&dcache_lock); - if (filldir(dirent, de->d_name.name, de->d_name.len, filp->f_pos, de->d_inode->i_ino, DT_UNKNOWN) < 0) - break; - spin_lock(&dcache_lock); - } - filp->f_pos++; - list = list->next; - if (list != &dentry->d_subdirs) - continue; - spin_unlock(&dcache_lock); - break; - } - } - } - return 0; -} - static int autofs4_dir_open(struct inode *inode, struct file *file) { struct dentry *dentry = file->f_dentry; - struct vfsmount *mnt = file->f_vfsmnt; struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); - int status; DPRINTK("file=%p dentry=%p %.*s", file, dentry, dentry->d_name.len, dentry->d_name.name); @@ -176,146 +81,31 @@ static int autofs4_dir_open(struct inode if (autofs4_oz_mode(sbi)) goto out; - if (autofs4_ispending(dentry)) { - DPRINTK("dentry busy"); - return -EBUSY; - } - - if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) { - struct nameidata nd; - int empty; - - /* In case there are stale directory dentrys from a failed mount */ - spin_lock(&dcache_lock); - empty = list_empty(&dentry->d_subdirs); + /* + * An empty directory in an autofs file system is always a + * mount point. The daemon must have failed to mount this + * during lookup so it doesn't exist. This can happen, for + * example, if user space returns an incorrect status for a + * mount request. Otherwise we're doing a readdir on the + * autofs file system so just let the libfs routines handle + * it. + */ + if (!d_mountpoint(dentry) && __simple_empty(dentry)) { spin_unlock(&dcache_lock); - - if (!empty) - d_invalidate(dentry); - - nd.flags = LOOKUP_DIRECTORY; - status = (dentry->d_op->d_revalidate)(dentry, &nd); - - if (!status) - return -ENOENT; + return -ENOENT; } + spin_unlock(&dcache_lock); - if (d_mountpoint(dentry)) { - struct file *fp = NULL; - struct vfsmount *fp_mnt = mntget(mnt); - struct dentry *fp_dentry = dget(dentry); - - if (!autofs4_follow_mount(&fp_mnt, &fp_dentry)) { - dput(fp_dentry); - mntput(fp_mnt); - return -ENOENT; - } - - fp = dentry_open(fp_dentry, fp_mnt, file->f_flags); - status = PTR_ERR(fp); - if (IS_ERR(fp)) { - file->private_data = NULL; - return status; - } - file->private_data = fp; - } -out: - return 0; -} - -static int autofs4_dir_close(struct inode *inode, struct file *file) -{ - struct dentry *dentry = file->f_dentry; - struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); - - DPRINTK("file=%p dentry=%p %.*s", - file, dentry, dentry->d_name.len, dentry->d_name.name); - - if (autofs4_oz_mode(sbi)) - goto out; - - if (autofs4_ispending(dentry)) { - DPRINTK("dentry busy"); - return -EBUSY; - } - - if (d_mountpoint(dentry)) { - struct file *fp = file->private_data; - - if (!fp) - return -ENOENT; - - filp_close(fp, current->files); - file->private_data = NULL; - } out: - return 0; + return dcache_dir_open(inode, file); } -static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir) +static int try_to_fill_dentry(struct dentry *dentry, int flags) { - struct dentry *dentry = file->f_dentry; struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); + struct autofs_info *ino = autofs4_dentry_ino(dentry); int status; - DPRINTK("file=%p dentry=%p %.*s", - file, dentry, dentry->d_name.len, dentry->d_name.name); - - if (autofs4_oz_mode(sbi)) - goto out; - - if (autofs4_ispending(dentry)) { - DPRINTK("dentry busy"); - return -EBUSY; - } - - if (d_mountpoint(dentry)) { - struct file *fp = file->private_data; - - if (!fp) - return -ENOENT; - - if (!fp->f_op || !fp->f_op->readdir) - goto out; - - status = vfs_readdir(fp, filldir, dirent); - file->f_pos = fp->f_pos; - if (status) - autofs4_copy_atime(file, fp); - return status; - } -out: - return autofs4_dcache_readdir(file, dirent, filldir); -} - -static int try_to_fill_dentry(struct dentry *dentry, - struct super_block *sb, - struct autofs_sb_info *sbi, int flags) -{ - struct autofs_info *de_info = autofs4_dentry_ino(dentry); - int status = 0; - - /* Block on any pending expiry here; invalidate the dentry - when expiration is done to trigger mount request with a new - dentry */ - if (de_info && (de_info->flags & AUTOFS_INF_EXPIRING)) { - DPRINTK("waiting for expire %p name=%.*s", - dentry, dentry->d_name.len, dentry->d_name.name); - - status = autofs4_wait(sbi, dentry, NFY_NONE); - - DPRINTK("expire done status=%d", status); - - /* - * If the directory still exists the mount request must - * continue otherwise it can't be followed at the right - * time during the walk. - */ - status = d_invalidate(dentry); - if (status != -EBUSY) - return 0; - } - DPRINTK("dentry=%p %.*s ino=%p", dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode); @@ -328,22 +118,19 @@ static int try_to_fill_dentry(struct den DPRINTK("mount done status=%d", status); - if (status && dentry->d_inode) - return 0; /* Try to get the kernel to invalidate this dentry */ - /* Turn this into a real negative dentry? */ if (status == -ENOENT) { - dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT; spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); - return 1; + return status; } else if (status) { /* Return a negative dentry, but leave it "pending" */ - return 1; + return status; } /* Trigger mount for path component or follow link */ - } else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) || + } else if (dentry->d_flags & DCACHE_AUTOFS_PENDING || + flags & (TRIGGER_FLAGS | TRIGGER_INTENTS) || current->link_count) { DPRINTK("waiting for mount name=%.*s", dentry->d_name.len, dentry->d_name.name); @@ -359,19 +146,96 @@ static int try_to_fill_dentry(struct den spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); - return 0; + return status; } } - /* We don't update the usages for the autofs daemon itself, this - is necessary for recursive autofs mounts */ - if (!autofs4_oz_mode(sbi)) - autofs4_update_usage(dentry); + /* Initialize expiry counter after successful mount */ + if (ino) + ino->last_used = jiffies; spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); - return 1; + + return 0; +} + +/* For autofs direct mounts the follow link triggers the mount */ +static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); + struct autofs_info *ino = autofs4_dentry_ino(dentry); + int oz_mode = autofs4_oz_mode(sbi); + unsigned int lookup_type; + int status; + + DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d", + dentry, dentry->d_name.len, dentry->d_name.name, oz_mode, + nd->flags); + /* + * For an expire of a covered direct or offset mount we need + * to beeak out of follow_down() at the autofs mount trigger + * (d_mounted--), so we can see the expiring flag, and manage + * the blocking and following here until the expire is completed. + */ + if (oz_mode) { + spin_lock(&sbi->fs_lock); + if (ino->flags & AUTOFS_INF_EXPIRING) { + spin_unlock(&sbi->fs_lock); + /* Follow down to our covering mount. */ + if (!follow_down(&nd->mnt, &nd->dentry)) + goto done; + goto follow; + } + spin_unlock(&sbi->fs_lock); + goto done; + } + + /* If an expire request is pending everyone must wait. */ + autofs4_expire_wait(dentry); + + /* We trigger a mount for almost all flags */ + lookup_type = nd->flags & (TRIGGER_FLAGS | TRIGGER_INTENTS); + if (!(lookup_type || dentry->d_flags & DCACHE_AUTOFS_PENDING)) + goto follow; + + /* + * If the dentry contains directories then it is an autofs + * multi-mount with no root mount offset. So don't try to + * mount it again. + */ + spin_lock(&dcache_lock); + if (dentry->d_flags & DCACHE_AUTOFS_PENDING || + (!d_mountpoint(dentry) && __simple_empty(dentry))) { + spin_unlock(&dcache_lock); + + status = try_to_fill_dentry(dentry, 0); + if (status) + goto out_error; + + goto follow; + } + spin_unlock(&dcache_lock); +follow: + /* + * If there is no root mount it must be an autofs + * multi-mount with no root offset so we don't need + * to follow it. + */ + if (d_mountpoint(dentry)) { + if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) { + status = -ENOENT; + goto out_error; + } + } + +done: + return NULL; + +out_error: + path_release(nd); + return ERR_PTR(status); } /* @@ -380,47 +244,76 @@ static int try_to_fill_dentry(struct den * yet completely filled in, and revalidate has to delay such * lookups.. */ -static int autofs4_revalidate(struct dentry * dentry, struct nameidata *nd) +static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) { - struct inode * dir = dentry->d_parent->d_inode; + struct inode *dir = dentry->d_parent->d_inode; struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); int oz_mode = autofs4_oz_mode(sbi); int flags = nd ? nd->flags : 0; - int status = 1; + int status; /* Pending dentry */ + spin_lock(&sbi->fs_lock); if (autofs4_ispending(dentry)) { - if (!oz_mode) - status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags); + /* The daemon never causes a mount to trigger */ + spin_unlock(&sbi->fs_lock); + + if (oz_mode) + return 1; + + /* + * If the directory has gone away due to an expire + * we have been called as ->d_revalidate() and so + * we need to return false and proceed to ->lookup(). + */ + if (autofs4_expire_wait(dentry) == -EAGAIN) + return 0; + + /* + * A zero status is success otherwise we have a + * negative error code. + */ + status = try_to_fill_dentry(dentry, flags); + if (status == 0) + return 1; + return status; } + spin_unlock(&sbi->fs_lock); /* Negative dentry.. invalidate if "old" */ if (dentry->d_inode == NULL) - return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT); + return 0; /* Check for a non-mountpoint directory with no contents */ spin_lock(&dcache_lock); if (S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) && - list_empty(&dentry->d_subdirs)) { + __simple_empty(dentry)) { DPRINTK("dentry=%p %.*s, emptydir", dentry, dentry->d_name.len, dentry->d_name.name); spin_unlock(&dcache_lock); - if (!oz_mode) - status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags); + + /* The daemon never causes a mount to trigger */ + if (oz_mode) + return 1; + + /* + * A zero status is success otherwise we have a + * negative error code. + */ + status = try_to_fill_dentry(dentry, flags); + if (status == 0) + return 1; + return status; } spin_unlock(&dcache_lock); - /* Update the usage list */ - if (!oz_mode) - autofs4_update_usage(dentry); - return 1; } -static void autofs4_dentry_release(struct dentry *de) +void autofs4_dentry_release(struct dentry *de) { struct autofs_info *inf; @@ -430,6 +323,17 @@ static void autofs4_dentry_release(struc de->d_fsdata = NULL; if (inf) { + struct autofs_sb_info *sbi = autofs4_sbi(de->d_sb); + + if (sbi) { + spin_lock(&sbi->lookup_lock); + if (!list_empty(&inf->active)) + list_del(&inf->active); + if (!list_empty(&inf->expiring)) + list_del(&inf->expiring); + spin_unlock(&sbi->lookup_lock); + } + inf->dentry = NULL; inf->inode = NULL; @@ -449,48 +353,192 @@ static struct dentry_operations autofs4_ .d_release = autofs4_dentry_release, }; +static struct dentry *autofs4_lookup_active(struct autofs_sb_info *sbi, struct dentry *parent, struct qstr *name) +{ + unsigned int len = name->len; + unsigned int hash = name->hash; + const unsigned char *str = name->name; + struct list_head *p, *head; + + spin_lock(&dcache_lock); + spin_lock(&sbi->lookup_lock); + head = &sbi->active_list; + list_for_each(p, head) { + struct autofs_info *ino; + struct dentry *dentry; + struct qstr *qstr; + + ino = list_entry(p, struct autofs_info, active); + dentry = ino->dentry; + + spin_lock(&dentry->d_lock); + + /* Already gone? */ + if (atomic_read(&dentry->d_count) == 0) + goto next; + + qstr = &dentry->d_name; + + if (dentry->d_name.hash != hash) + goto next; + if (dentry->d_parent != parent) + goto next; + + if (qstr->len != len) + goto next; + if (memcmp(qstr->name, str, len)) + goto next; + + if (d_unhashed(dentry)) { + dget(dentry); + spin_unlock(&dentry->d_lock); + spin_unlock(&sbi->lookup_lock); + spin_unlock(&dcache_lock); + return dentry; + } +next: + spin_unlock(&dentry->d_lock); + } + spin_unlock(&sbi->lookup_lock); + spin_unlock(&dcache_lock); + + return NULL; +} + +static struct dentry *autofs4_lookup_expiring(struct autofs_sb_info *sbi, struct dentry *parent, struct qstr *name) +{ + unsigned int len = name->len; + unsigned int hash = name->hash; + const unsigned char *str = name->name; + struct list_head *p, *head; + + spin_lock(&dcache_lock); + spin_lock(&sbi->lookup_lock); + head = &sbi->expiring_list; + list_for_each(p, head) { + struct autofs_info *ino; + struct dentry *dentry; + struct qstr *qstr; + + ino = list_entry(p, struct autofs_info, expiring); + dentry = ino->dentry; + + spin_lock(&dentry->d_lock); + + /* Bad luck, we've already been dentry_iput */ + if (!dentry->d_inode) + goto next; + + qstr = &dentry->d_name; + + if (dentry->d_name.hash != hash) + goto next; + if (dentry->d_parent != parent) + goto next; + + if (qstr->len != len) + goto next; + if (memcmp(qstr->name, str, len)) + goto next; + + if (d_unhashed(dentry)) { + dget(dentry); + spin_unlock(&dentry->d_lock); + spin_unlock(&sbi->lookup_lock); + spin_unlock(&dcache_lock); + return dentry; + } +next: + spin_unlock(&dentry->d_lock); + } + spin_unlock(&sbi->lookup_lock); + spin_unlock(&dcache_lock); + + return NULL; +} + /* Lookups in the root directory */ static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { struct autofs_sb_info *sbi; + struct autofs_info *ino; + struct dentry *expiring, *unhashed; int oz_mode; DPRINTK("name = %.*s", dentry->d_name.len, dentry->d_name.name); + /* File name too long to exist */ if (dentry->d_name.len > NAME_MAX) - return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */ + return ERR_PTR(-ENAMETOOLONG); sbi = autofs4_sbi(dir->i_sb); - oz_mode = autofs4_oz_mode(sbi); + DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d", current->pid, process_group(current), sbi->catatonic, oz_mode); - /* - * Mark the dentry incomplete, but add it. This is needed so - * that the VFS layer knows about the dentry, and we can count - * on catching any lookups through the revalidate. - * - * Let all the hard work be done by the revalidate function that - * needs to be able to do this anyway.. - * - * We need to do this before we release the directory semaphore. - */ - dentry->d_op = &autofs4_root_dentry_operations; + expiring = autofs4_lookup_expiring(sbi, dentry->d_parent, &dentry->d_name); + if (expiring) { + /* + * If we are racing with expire the request might not + * be quite complete but the directory has been removed + * so it must have been successful, so just wait for it. + */ + ino = autofs4_dentry_ino(expiring); + autofs4_expire_wait(expiring); + spin_lock(&sbi->lookup_lock); + if (!list_empty(&ino->expiring)) + list_del_init(&ino->expiring); + spin_unlock(&sbi->lookup_lock); + dput(expiring); + } + + unhashed = autofs4_lookup_active(sbi, dentry->d_parent, &dentry->d_name); + if (unhashed) + dentry = unhashed; + else { + /* + * Mark the dentry incomplete but don't hash it. We do this + * to serialize our inode creation operations (symlink and + * mkdir) which prevents deadlock during the callback to + * the daemon. Subsequent user space lookups for the same + * dentry are placed on the wait queue while the daemon + * itself is allowed passage unresticted so the create + * operation itself can then hash the dentry. Finally, + * we check for the hashed dentry and return the newly + * hashed dentry. + */ + dentry->d_op = &autofs4_root_dentry_operations; + + /* + * And we need to ensure that the same dentry is used for + * all following lookup calls until it is hashed so that + * the dentry flags are persistent throughout the request. + */ + ino = autofs4_init_ino(NULL, sbi, 0555); + if (!ino) + return ERR_PTR(-ENOMEM); + + dentry->d_fsdata = ino; + ino->dentry = dentry; + + spin_lock(&sbi->lookup_lock); + list_add(&ino->active, &sbi->active_list); + spin_unlock(&sbi->lookup_lock); + + d_instantiate(dentry, NULL); + } if (!oz_mode) { spin_lock(&dentry->d_lock); dentry->d_flags |= DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); - } - dentry->d_fsdata = NULL; - d_add(dentry, NULL); - - if (dentry->d_op && dentry->d_op->d_revalidate) { - up(&dir->i_sem); - (dentry->d_op->d_revalidate)(dentry, nd); - down(&dir->i_sem); + if (dentry->d_op && dentry->d_op->d_revalidate) { + up(&dir->i_sem); + (dentry->d_op->d_revalidate)(dentry, nd); + down(&dir->i_sem); + } } /* @@ -504,19 +552,47 @@ static struct dentry *autofs4_lookup(str if (sigismember (sigset, SIGKILL) || sigismember (sigset, SIGQUIT) || sigismember (sigset, SIGINT)) { + if (unhashed) + dput(unhashed); return ERR_PTR(-ERESTARTNOINTR); } } + if (!oz_mode) { + spin_lock(&dentry->d_lock); + dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; + spin_unlock(&dentry->d_lock); + } } /* * If this dentry is unhashed, then we shouldn't honour this - * lookup even if the dentry is positive. Returning ENOENT here - * doesn't do the right thing for all system calls, but it should - * be OK for the operations we permit from an autofs. + * lookup. Returning ENOENT here doesn't do the right thing + * for all system calls, but it should be OK for the operations + * we permit from an autofs. */ - if ( dentry->d_inode && d_unhashed(dentry) ) - return ERR_PTR(-ENOENT); + if (!oz_mode && d_unhashed(dentry)) { + /* + * A user space application can (and has done in the past) + * remove and re-create this directory during the callback. + * This can leave us with an unhashed dentry, but a + * successful mount! So we need to perform another + * cached lookup in case the dentry now exists. + */ + struct dentry *parent = dentry->d_parent; + struct dentry *new = d_lookup(parent, &dentry->d_name); + if (new != NULL) + dentry = new; + else + dentry = ERR_PTR(-ENOENT); + + if (unhashed) + dput(unhashed); + + return dentry; + } + + if (unhashed) + return unhashed; return NULL; } @@ -527,6 +603,7 @@ static int autofs4_dir_symlink(struct in { struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct autofs_info *p_ino; struct inode *inode; char *cp; @@ -537,21 +614,32 @@ static int autofs4_dir_symlink(struct in return -EACCES; ino = autofs4_init_ino(ino, sbi, S_IFLNK | 0555); - if (ino == NULL) - return -ENOSPC; + if (!ino) + return -ENOMEM; - ino->size = strlen(symname); - ino->u.symlink = cp = kmalloc(ino->size + 1, GFP_KERNEL); + spin_lock(&sbi->lookup_lock); + if (!list_empty(&ino->active)) + list_del_init(&ino->active); + spin_unlock(&sbi->lookup_lock); - if (cp == NULL) { - kfree(ino); - return -ENOSPC; + ino->size = strlen(symname); + cp = kmalloc(ino->size + 1, GFP_KERNEL); + if (!cp) { + if (!dentry->d_fsdata) + kfree(ino); + return -ENOMEM; } strcpy(cp, symname); inode = autofs4_get_inode(dir->i_sb, ino); - d_instantiate(dentry, inode); + if (!inode) { + kfree(cp); + if (!dentry->d_fsdata) + kfree(ino); + return -ENOMEM; + } + d_add(dentry, inode); if (dir == dir->i_sb->s_root->d_inode) dentry->d_op = &autofs4_root_dentry_operations; @@ -560,8 +648,13 @@ static int autofs4_dir_symlink(struct in dentry->d_fsdata = ino; ino->dentry = dget(dentry); + atomic_inc(&ino->count); + p_ino = autofs4_dentry_ino(dentry->d_parent); + if (p_ino && dentry->d_parent != dentry) + atomic_inc(&p_ino->count); ino->inode = inode; + ino->u.symlink = cp; dir->i_mtime = CURRENT_TIME; return 0; @@ -573,9 +666,9 @@ static int autofs4_dir_symlink(struct in * Normal filesystems would do a "d_delete()" to tell the VFS dcache * that the file no longer exists. However, doing that means that the * VFS layer can turn the dentry into a negative dentry. We don't want - * this, because since the unlink is probably the result of an expire. - * We simply d_drop it, which allows the dentry lookup to remount it - * if necessary. + * this, because the unlink is probably the result of an expire. + * We simply d_drop it and add it to a expiring list in the super block, + * which allows the dentry lookup to check for an incomplete expire. * * If a process is blocked on the dentry waiting for the expire to finish, * it will invalidate the dentry and try to mount with a new one. @@ -586,11 +679,17 @@ static int autofs4_dir_unlink(struct ino { struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct autofs_info *p_ino; /* This allows root to remove symlinks */ if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) ) return -EACCES; + if (atomic_dec_and_test(&ino->count)) { + p_ino = autofs4_dentry_ino(dentry->d_parent); + if (p_ino && dentry->d_parent != dentry) + atomic_dec(&p_ino->count); + } dput(ino->dentry); dentry->d_inode->i_size = 0; @@ -598,7 +697,15 @@ static int autofs4_dir_unlink(struct ino dir->i_mtime = CURRENT_TIME; - d_drop(dentry); + spin_lock(&dcache_lock); + spin_lock(&sbi->lookup_lock); + if (list_empty(&ino->expiring)) + list_add(&ino->expiring, &sbi->expiring_list); + spin_unlock(&sbi->lookup_lock); + spin_lock(&dentry->d_lock); + __d_drop(dentry); + spin_unlock(&dentry->d_lock); + spin_unlock(&dcache_lock); return 0; } @@ -607,7 +714,11 @@ static int autofs4_dir_rmdir(struct inod { struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct autofs_info *p_ino; + DPRINTK("dentry %p, removing %.*s", + dentry, dentry->d_name.len, dentry->d_name.name); + if (!autofs4_oz_mode(sbi)) return -EACCES; @@ -616,13 +727,21 @@ static int autofs4_dir_rmdir(struct inod spin_unlock(&dcache_lock); return -ENOTEMPTY; } + spin_lock(&sbi->lookup_lock); + if (list_empty(&ino->expiring)) + list_add(&ino->expiring, &sbi->expiring_list); + spin_unlock(&sbi->lookup_lock); spin_lock(&dentry->d_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); + if (atomic_dec_and_test(&ino->count)) { + p_ino = autofs4_dentry_ino(dentry->d_parent); + if (p_ino && dentry->d_parent != dentry) + atomic_dec(&p_ino->count); + } dput(ino->dentry); - dentry->d_inode->i_size = 0; dentry->d_inode->i_nlink = 0; @@ -636,6 +755,7 @@ static int autofs4_dir_mkdir(struct inod { struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct autofs_info *p_ino; struct inode *inode; if ( !autofs4_oz_mode(sbi) ) @@ -645,11 +765,21 @@ static int autofs4_dir_mkdir(struct inod dentry, dentry->d_name.len, dentry->d_name.name); ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555); - if (ino == NULL) - return -ENOSPC; + if (!ino) + return -ENOMEM; + + spin_lock(&sbi->lookup_lock); + if (!list_empty(&ino->active)) + list_del_init(&ino->active); + spin_unlock(&sbi->lookup_lock); inode = autofs4_get_inode(dir->i_sb, ino); - d_instantiate(dentry, inode); + if (!inode) { + if (!dentry->d_fsdata) + kfree(ino); + return -ENOMEM; + } + d_add(dentry, inode); if (dir == dir->i_sb->s_root->d_inode) dentry->d_op = &autofs4_root_dentry_operations; @@ -658,6 +788,10 @@ static int autofs4_dir_mkdir(struct inod dentry->d_fsdata = ino; ino->dentry = dget(dentry); + atomic_inc(&ino->count); + p_ino = autofs4_dentry_ino(dentry->d_parent); + if (p_ino && dentry->d_parent != dentry) + atomic_inc(&p_ino->count); ino->inode = inode; dir->i_nlink++; dir->i_mtime = CURRENT_TIME; @@ -697,51 +831,13 @@ static inline int autofs4_get_protosubve } /* - * Tells the daemon whether we need to reghost or not. Also, clears - * the reghost_needed flag. - */ -static inline int autofs4_ask_reghost(struct autofs_sb_info *sbi, int __user *p) -{ - int status; - - DPRINTK("returning %d", sbi->needs_reghost); - - status = put_user(sbi->needs_reghost, p); - if ( status ) - return status; - - sbi->needs_reghost = 0; - return 0; -} - -/* - * Enable / Disable reghosting ioctl() operation - */ -static inline int autofs4_toggle_reghost(struct autofs_sb_info *sbi, int __user *p) -{ - int status; - int val; - - status = get_user(val, p); - - DPRINTK("reghost = %d", val); - - if (status) - return status; - - /* turn on/off reghosting, with the val */ - sbi->reghost_enabled = val; - return 0; -} - -/* * Tells the daemon whether it can umount the autofs mount. */ static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *p) { int status = 0; - if (may_umount(mnt) == 0) + if (may_umount(mnt)) status = 1; DPRINTK("returning %d", status); @@ -798,11 +894,6 @@ static int autofs4_root_ioctl(struct ino case AUTOFS_IOC_SETTIMEOUT: return autofs4_get_set_timeout(sbi, p); - case AUTOFS_IOC_TOGGLEREGHOST: - return autofs4_toggle_reghost(sbi, p); - case AUTOFS_IOC_ASKREGHOST: - return autofs4_ask_reghost(sbi, p); - case AUTOFS_IOC_ASKUMOUNT: return autofs4_ask_umount(filp->f_vfsmnt, p); Index: linux-2.6.13/fs/autofs4/autofs_i.h =================================================================== --- linux-2.6.13/fs/autofs4/autofs_i.h +++ linux-2.6.13/fs/autofs4/autofs_i.h @@ -3,6 +3,7 @@ * linux/fs/autofs/autofs_i.h * * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved + * Copyright 2005-2006 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 @@ -19,6 +20,8 @@ #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY #define AUTOFS_IOC_COUNT 32 +#define AUTOFS_TYPE_TRIGGER (AUTOFS_TYPE_DIRECT|AUTOFS_TYPE_OFFSET) + #include #include #include @@ -40,14 +43,6 @@ #define AUTOFS_SUPER_MAGIC 0x0187 -/* - * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the - * kernel will keep the negative response cached for up to the time given - * here, although the time can be shorter if the kernel throws the dcache - * entry away. This probably should be settable from user space. - */ -#define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */ - /* Unified info structure. This is pointed to by both the dentry and inode structures. Each file in the filesystem has an instance of this structure. It holds a reference to the dentry, so dentries are never @@ -60,8 +55,14 @@ struct autofs_info { int flags; + struct completion expire_complete; + + struct list_head active; + struct list_head expiring; + struct autofs_sb_info *sbi; unsigned long last_used; + atomic_t count; mode_t mode; size_t size; @@ -73,38 +74,48 @@ struct autofs_info { }; #define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */ +#define AUTOFS_INF_MOUNTPOINT (1<<1) /* mountpoint status for direct expire */ struct autofs_wait_queue { wait_queue_head_t queue; struct autofs_wait_queue *next; autofs_wqt_t wait_queue_token; /* We use the following to see what we are waiting for */ - int hash; - int len; - char *name; + struct qstr name; + u32 dev; + u64 ino; + uid_t uid; + gid_t gid; + pid_t pid; + pid_t tgid; /* This is for status reporting upon return */ int status; - atomic_t notified; - atomic_t wait_ctr; + unsigned int wait_ctr; }; #define AUTOFS_SBI_MAGIC 0x6d4a556d struct autofs_sb_info { u32 magic; - struct dentry *root; + int pipefd; struct file *pipe; pid_t oz_pgrp; int catatonic; int version; int sub_version; + int min_proto; + int max_proto; unsigned long exp_timeout; + unsigned int type; int reghost_enabled; int needs_reghost; struct super_block *sb; struct semaphore wq_sem; spinlock_t fs_lock; struct autofs_wait_queue *queues; /* Wait queue pointer */ + spinlock_t lookup_lock; + struct list_head active_list; + struct list_head expiring_list; }; static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) @@ -129,18 +140,14 @@ static inline int autofs4_oz_mode(struct static inline int autofs4_ispending(struct dentry *dentry) { struct autofs_info *inf = autofs4_dentry_ino(dentry); - int pending = 0; if (dentry->d_flags & DCACHE_AUTOFS_PENDING) return 1; - if (inf) { - spin_lock(&inf->sbi->fs_lock); - pending = inf->flags & AUTOFS_INF_EXPIRING; - spin_unlock(&inf->sbi->fs_lock); - } + if (inf->flags & AUTOFS_INF_EXPIRING) + return 1; - return pending; + return 0; } static inline void autofs4_copy_atime(struct file *src, struct file *dst) @@ -154,6 +161,7 @@ void autofs4_free_ino(struct autofs_info /* Expiration */ int is_autofs4_dentry(struct dentry *); +int autofs4_expire_wait(struct dentry *dentry); int autofs4_expire_run(struct super_block *, struct vfsmount *, struct autofs_sb_info *, struct autofs_packet_expire __user *); @@ -165,6 +173,8 @@ int autofs4_expire_multi(struct super_bl extern struct inode_operations autofs4_symlink_inode_operations; extern struct inode_operations autofs4_dir_inode_operations; extern struct inode_operations autofs4_root_inode_operations; +extern struct inode_operations autofs4_indirect_root_inode_operations; +extern struct inode_operations autofs4_direct_root_inode_operations; extern struct file_operations autofs4_dir_operations; extern struct file_operations autofs4_root_operations; @@ -175,13 +185,6 @@ struct autofs_info *autofs4_init_ino(str /* Queue management functions */ -enum autofs_notify -{ - NFY_NONE, - NFY_MOUNT, - NFY_EXPIRE -}; - int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify); int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); void autofs4_catatonic_mode(struct autofs_sb_info *); @@ -199,12 +202,22 @@ static inline int autofs4_follow_mount(s return res; } +static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi) +{ + return new_encode_dev(sbi->sb->s_dev); +} + +static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi) +{ + return sbi->sb->s_root->d_inode->i_ino; +} + static inline int simple_positive(struct dentry *dentry) { return dentry->d_inode && !d_unhashed(dentry); } -static inline int simple_empty_nolock(struct dentry *dentry) +static inline int __simple_empty(struct dentry *dentry) { struct dentry *child; int ret = 0; @@ -216,3 +229,6 @@ static inline int simple_empty_nolock(st out: return ret; } + +void autofs4_dentry_release(struct dentry *); +extern void autofs4_kill_sb(struct super_block *); Index: linux-2.6.13/fs/autofs4/expire.c =================================================================== --- linux-2.6.13/fs/autofs4/expire.c +++ linux-2.6.13/fs/autofs4/expire.c @@ -4,7 +4,7 @@ * * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved * Copyright 1999-2000 Jeremy Fitzhardinge - * 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 @@ -16,7 +16,7 @@ static unsigned long now; -/* Check if a dentry can be expired return 1 if it can else return 0 */ +/* Check if a dentry can be expired */ static inline int autofs4_can_expire(struct dentry *dentry, unsigned long timeout, int do_now) { @@ -41,14 +41,14 @@ static inline int autofs4_can_expire(str attempts if expire fails the first time */ ino->last_used = now; } - return 1; } -/* Check a mount point for busyness return 1 if not busy, otherwise */ -static int autofs4_check_mount(struct vfsmount *mnt, struct dentry *dentry) +/* Check a mount point for busyness */ +static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry) { - int status = 0; + struct dentry *top = dentry; + int status = 1; DPRINTK("dentry %p %.*s", dentry, (int)dentry->d_name.len, dentry->d_name.name); @@ -56,95 +56,163 @@ static int autofs4_check_mount(struct vf mntget(mnt); dget(dentry); - if (!autofs4_follow_mount(&mnt, &dentry)) + if (!follow_down(&mnt, &dentry)) goto done; - /* This is an autofs submount, we can't expire it */ - if (is_autofs4_dentry(dentry)) + if (is_autofs4_dentry(dentry)) { + struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); + + /* This is an autofs submount, we can't expire it */ + if (sbi->type == AUTOFS_TYPE_INDIRECT) + goto done; + + /* + * Otherwise it's an offset mount and we need to check + * if we can umount its mount, if there is one. + */ + if (!d_mountpoint(dentry)) + goto done; + } + + /* Update the expiry counter if fs is busy */ + if (!may_umount_tree(mnt)) { + struct autofs_info *ino = autofs4_dentry_ino(top); + ino->last_used = jiffies; goto done; + } - /* The big question */ - if (may_umount_tree(mnt) == 0) - status = 1; + status = 0; done: DPRINTK("returning = %d", status); - mntput(mnt); dput(dentry); + mntput(mnt); return status; } +/* + * Calculate next entry in top down tree traversal. + * From next_mnt in namespace.c - elegant. + */ +static struct dentry *next_dentry(struct dentry *p, struct dentry *root) +{ + struct list_head *next = p->d_subdirs.next; + + if (next == &p->d_subdirs) { + while (1) { + if (p == root) + return NULL; + next = p->d_child.next; + if (next != &p->d_parent->d_subdirs) + break; + p = p->d_parent; + } + } + return list_entry(next, struct dentry, d_child); +} + +/* + * Check a direct mount point for busyness. + * Direct mounts have similar expiry semantics to tree mounts. + * The tree is not busy iff no mountpoints are busy and there are no + * autofs submounts. + */ +static int autofs4_direct_busy(struct vfsmount *mnt, + struct dentry *top, + unsigned long timeout, + int do_now) +{ + DPRINTK("top %p %.*s", + top, (int) top->d_name.len, top->d_name.name); + + /* If it's busy update the expiry counters */ + if (!may_umount_tree(mnt)) { + struct autofs_info *ino = autofs4_dentry_ino(top); + if (ino) + ino->last_used = jiffies; + return 1; + } + + /* Timeout of a direct mount is determined by its top dentry */ + if (!autofs4_can_expire(top, timeout, do_now)) + return 1; + + return 0; +} + /* Check a directory tree of mount points for busyness * The tree is not busy iff no mountpoints are busy - * Return 1 if the tree is busy or 0 otherwise */ -static int autofs4_check_tree(struct vfsmount *mnt, - struct dentry *top, - unsigned long timeout, - int do_now) +static int autofs4_tree_busy(struct vfsmount *mnt, + struct dentry *top, + unsigned long timeout, + int do_now) { - struct dentry *this_parent = top; - struct list_head *next; + struct autofs_info *top_ino = autofs4_dentry_ino(top); + struct dentry *p; - DPRINTK("parent %p %.*s", + DPRINTK("top %p %.*s", top, (int)top->d_name.len, top->d_name.name); /* Negative dentry - give up */ if (!simple_positive(top)) - return 0; - - /* Timeout of a tree mount is determined by its top dentry */ - if (!autofs4_can_expire(top, timeout, do_now)) - return 0; - - /* Is someone visiting anywhere in the tree ? */ - if (may_umount_tree(mnt)) - return 0; + return 1; spin_lock(&dcache_lock); -repeat: - next = this_parent->d_subdirs.next; -resume: - while (next != &this_parent->d_subdirs) { - struct dentry *dentry = list_entry(next, struct dentry, d_child); - + for (p = top; p; p = next_dentry(p, top)) { /* Negative dentry - give up */ - if (!simple_positive(dentry)) { - next = next->next; + if (!simple_positive(p)) continue; - } DPRINTK("dentry %p %.*s", - dentry, (int)dentry->d_name.len, dentry->d_name.name); + p, (int) p->d_name.len, p->d_name.name); - if (!simple_empty_nolock(dentry)) { - this_parent = dentry; - goto repeat; - } - - dentry = dget(dentry); + p = dget(p); spin_unlock(&dcache_lock); - if (d_mountpoint(dentry)) { - /* First busy => tree busy */ - if (!autofs4_check_mount(mnt, dentry)) { - dput(dentry); - return 0; + /* + * Is someone visiting anywhere in the subtree ? + * If there's no mount we need to check the usage + * count for the autofs dentry. + * If the fs is busy update the expiry counter. + */ + if (d_mountpoint(p)) { + if (autofs4_mount_busy(mnt, p)) { + top_ino->last_used = jiffies; + dput(p); + return 1; } - } + } else { + struct autofs_info *ino = autofs4_dentry_ino(p); + unsigned int ino_count = atomic_read(&ino->count); - dput(dentry); + /* + * Clean stale dentries below that have not been + * invalidated after a mount fail during lookup + */ + d_invalidate(p); + + /* allow for dget above and top is already dgot */ + if (p == top) + ino_count += 2; + else + ino_count++; + + if (atomic_read(&p->d_count) > ino_count) { + top_ino->last_used = jiffies; + dput(p); + return 1; + } + } + dput(p); spin_lock(&dcache_lock); - next = next->next; - } - - if (this_parent != top) { - next = this_parent->d_child.next; - this_parent = this_parent->d_parent; - goto resume; } spin_unlock(&dcache_lock); - return 1; + /* Timeout of a tree mount is ultimately determined by its top dentry */ + if (!autofs4_can_expire(top, timeout, do_now)) + return 1; + + return 0; } static struct dentry *autofs4_check_leaves(struct vfsmount *mnt, @@ -152,58 +220,70 @@ static struct dentry *autofs4_check_leav unsigned long timeout, int do_now) { - struct dentry *this_parent = parent; - struct list_head *next; + struct dentry *p; DPRINTK("parent %p %.*s", parent, (int)parent->d_name.len, parent->d_name.name); spin_lock(&dcache_lock); -repeat: - next = this_parent->d_subdirs.next; -resume: - while (next != &this_parent->d_subdirs) { - struct dentry *dentry = list_entry(next, struct dentry, d_child); - + for (p = parent; p; p = next_dentry(p, parent)) { /* Negative dentry - give up */ - if (!simple_positive(dentry)) { - next = next->next; + if (!simple_positive(p)) continue; - } DPRINTK("dentry %p %.*s", - dentry, (int)dentry->d_name.len, dentry->d_name.name); - - if (!list_empty(&dentry->d_subdirs)) { - this_parent = dentry; - goto repeat; - } + p, (int) p->d_name.len, p->d_name.name); - dentry = dget(dentry); + p = dget(p); spin_unlock(&dcache_lock); - if (d_mountpoint(dentry)) { - /* Can we expire this guy */ - if (!autofs4_can_expire(dentry, timeout, do_now)) - goto cont; - + if (d_mountpoint(p)) { /* Can we umount this guy */ - if (autofs4_check_mount(mnt, dentry)) - return dentry; + if (autofs4_mount_busy(mnt, p)) + goto cont; + /* Can we expire this guy */ + if (autofs4_can_expire(p, timeout, do_now)) + return p; } cont: - dput(dentry); + dput(p); spin_lock(&dcache_lock); - next = next->next; } + spin_unlock(&dcache_lock); + return NULL; +} + +/* Check if we can expire a direct mount (possibly a tree) */ +static struct dentry *autofs4_expire_direct(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, + int how) +{ + unsigned long timeout; + struct dentry *root = dget(sb->s_root); + int do_now = how & AUTOFS_EXP_IMMEDIATE; + + if (!sbi->exp_timeout || !root) + return NULL; + + now = jiffies; + timeout = sbi->exp_timeout; - if (this_parent != parent) { - next = this_parent->d_child.next; - this_parent = this_parent->d_parent; - goto resume; + spin_lock(&sbi->fs_lock); + if (!autofs4_direct_busy(mnt, root, timeout, do_now)) { + struct autofs_info *ino = autofs4_dentry_ino(root); + if (d_mountpoint(root)) { + ino->flags |= AUTOFS_INF_MOUNTPOINT; + root->d_mounted--; + } + ino->flags |= AUTOFS_INF_EXPIRING; + init_completion(&ino->expire_complete); + spin_unlock(&sbi->fs_lock); + return root; } - spin_unlock(&dcache_lock); + spin_unlock(&sbi->fs_lock); + dput(root); return NULL; } @@ -214,10 +294,10 @@ cont: * - it is unused by any user process * - it has been unused for exp_timeout time */ -static struct dentry *autofs4_expire(struct super_block *sb, - struct vfsmount *mnt, - struct autofs_sb_info *sbi, - int how) +static struct dentry *autofs4_expire_indirect(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, + int how) { unsigned long timeout; struct dentry *root = sb->s_root; @@ -225,6 +305,8 @@ static struct dentry *autofs4_expire(str struct list_head *next; int do_now = how & AUTOFS_EXP_IMMEDIATE; int exp_leaves = how & AUTOFS_EXP_LEAVES; + struct autofs_info *ino; + unsigned int ino_count; if ( !sbi->exp_timeout || !root ) return NULL; @@ -241,7 +323,7 @@ static struct dentry *autofs4_expire(str struct dentry *dentry = list_entry(next, struct dentry, d_child); /* Negative dentry - give up */ - if ( !simple_positive(dentry) ) { + if (!simple_positive(dentry)) { next = next->next; continue; } @@ -249,66 +331,116 @@ static struct dentry *autofs4_expire(str dentry = dget(dentry); spin_unlock(&dcache_lock); - /* Case 1: indirect mount or top level direct mount */ + spin_lock(&sbi->fs_lock); + ino = autofs4_dentry_ino(dentry); + + /* + * Case 1: (i) indirect mount or top level pseudo direct mount + * (autofs-4.1). + * (ii) indirect mount with offset mount, check the "/" + * offset (autofs-5.0+). + */ if (d_mountpoint(dentry)) { DPRINTK("checking mountpoint %p %.*s", dentry, (int)dentry->d_name.len, dentry->d_name.name); - /* Can we expire this guy */ - if (!autofs4_can_expire(dentry, timeout, do_now)) + /* Path walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 2; + if (atomic_read(&dentry->d_count) > ino_count) goto next; /* Can we umount this guy */ - if (autofs4_check_mount(mnt, dentry)) { + if (autofs4_mount_busy(mnt, dentry)) + goto next; + + /* Can we expire this guy */ + if (autofs4_can_expire(dentry, timeout, do_now)) { expired = dentry; - break; + goto found; } goto next; } - if ( simple_empty(dentry) ) + if (simple_empty(dentry)) goto next; /* Case 2: tree mount, expire iff entire tree is not busy */ if (!exp_leaves) { - /* Lock the tree as we must expire as a whole */ - spin_lock(&sbi->fs_lock); - if (autofs4_check_tree(mnt, dentry, timeout, do_now)) { - struct autofs_info *inf = autofs4_dentry_ino(dentry); - - /* Set this flag early to catch sys_chdir and the like */ - inf->flags |= AUTOFS_INF_EXPIRING; - spin_unlock(&sbi->fs_lock); + /* Path walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (atomic_read(&dentry->d_count) > ino_count) + goto next; + + if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) { expired = dentry; - break; + goto found; } - spin_unlock(&sbi->fs_lock); - /* Case 3: direct mount, expire individual leaves */ + /* + * Case 3: pseudo direct mount, expire individual leaves + * (autofs-4.1). + */ } else { + /* Path walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (atomic_read(&dentry->d_count) > ino_count) + goto next; + expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); if (expired) { dput(dentry); - break; + goto found; } } next: + spin_unlock(&sbi->fs_lock); dput(dentry); spin_lock(&dcache_lock); next = next->next; } + spin_unlock(&dcache_lock); + return NULL; - if ( expired ) { - DPRINTK("returning %p %.*s", - expired, (int)expired->d_name.len, expired->d_name.name); - spin_lock(&dcache_lock); - list_del(&expired->d_parent->d_subdirs); - list_add(&expired->d_parent->d_subdirs, &expired->d_child); - spin_unlock(&dcache_lock); - return expired; - } +found: + DPRINTK("returning %p %.*s", + expired, (int)expired->d_name.len, expired->d_name.name); + ino = autofs4_dentry_ino(expired); + ino->flags |= AUTOFS_INF_EXPIRING; + init_completion(&ino->expire_complete); + spin_unlock(&sbi->fs_lock); + spin_lock(&dcache_lock); + list_del(&expired->d_parent->d_subdirs); + list_add(&expired->d_parent->d_subdirs, &expired->d_child); spin_unlock(&dcache_lock); + return expired; +} - return NULL; +int autofs4_expire_wait(struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); + struct autofs_info *ino = autofs4_dentry_ino(dentry); + int status; + + /* Block on any pending expire */ + spin_lock(&sbi->fs_lock); + if (ino->flags & AUTOFS_INF_EXPIRING) { + spin_unlock(&sbi->fs_lock); + + DPRINTK("waiting for expire %p name=%.*s", + dentry, dentry->d_name.len, dentry->d_name.name); + + status = autofs4_wait(sbi, dentry, NFY_NONE); + wait_for_completion(&ino->expire_complete); + + DPRINTK("expire done status=%d", status); + + if (d_unhashed(dentry)) + return -EAGAIN; + + return status; + } + spin_unlock(&sbi->fs_lock); + + return 0; } /* Perform an expiry operation */ @@ -318,14 +450,16 @@ int autofs4_expire_run(struct super_bloc struct autofs_packet_expire __user *pkt_p) { struct autofs_packet_expire pkt; + struct autofs_info *ino; struct dentry *dentry; + int ret = 0; memset(&pkt,0,sizeof pkt); pkt.hdr.proto_version = sbi->version; pkt.hdr.type = autofs_ptype_expire; - if ((dentry = autofs4_expire(sb, mnt, sbi, 0)) == NULL) + if ((dentry = autofs4_expire_indirect(sb, mnt, sbi, 0)) == NULL) return -EAGAIN; pkt.len = dentry->d_name.len; @@ -334,9 +468,15 @@ int autofs4_expire_run(struct super_bloc dput(dentry); if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) ) - return -EFAULT; + ret = -EFAULT; - return 0; + spin_lock(&sbi->fs_lock); + ino = autofs4_dentry_ino(dentry); + ino->flags &= ~AUTOFS_INF_EXPIRING; + complete_all(&ino->expire_complete); + spin_unlock(&sbi->fs_lock); + + return ret; } /* Call repeatedly until it returns -EAGAIN, meaning there's nothing @@ -351,17 +491,29 @@ int autofs4_expire_multi(struct super_bl if (arg && get_user(do_now, arg)) return -EFAULT; - if ((dentry = autofs4_expire(sb, mnt, sbi, do_now)) != NULL) { - struct autofs_info *de_info = autofs4_dentry_ino(dentry); + if (sbi->type & AUTOFS_TYPE_TRIGGER) + dentry = autofs4_expire_direct(sb, mnt, sbi, do_now); + else + dentry = autofs4_expire_indirect(sb, mnt, sbi, do_now); + + if (dentry) { + struct autofs_info *ino = autofs4_dentry_ino(dentry); /* This is synchronous because it makes the daemon a little easier */ - de_info->flags |= AUTOFS_INF_EXPIRING; ret = autofs4_wait(sbi, dentry, NFY_EXPIRE); - de_info->flags &= ~AUTOFS_INF_EXPIRING; + + spin_lock(&sbi->fs_lock); + if (ino->flags & AUTOFS_INF_MOUNTPOINT) { + sb->s_root->d_mounted++; + ino->flags &= ~AUTOFS_INF_MOUNTPOINT; + } + ino->flags &= ~AUTOFS_INF_EXPIRING; + complete_all(&ino->expire_complete); + spin_unlock(&sbi->fs_lock); dput(dentry); } - + return ret; } Index: linux-2.6.13/fs/autofs4/inode.c =================================================================== --- linux-2.6.13/fs/autofs4/inode.c +++ linux-2.6.13/fs/autofs4/inode.c @@ -3,6 +3,7 @@ * linux/fs/autofs/inode.c * * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * Copyright 2005-2006 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 @@ -13,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -41,12 +43,17 @@ struct autofs_info *autofs4_init_ino(str if (ino == NULL) return NULL; - ino->flags = 0; - ino->mode = mode; - ino->inode = NULL; - ino->dentry = NULL; - ino->size = 0; + if (!reinit) { + ino->flags = 0; + ino->inode = NULL; + ino->dentry = NULL; + ino->size = 0; + INIT_LIST_HEAD(&ino->active); + INIT_LIST_HEAD(&ino->expiring); + atomic_set(&ino->count, 0); + } + ino->mode = mode; ino->last_used = jiffies; ino->sbi = sbi; @@ -66,10 +73,19 @@ struct autofs_info *autofs4_init_ino(str void autofs4_free_ino(struct autofs_info *ino) { + struct autofs_info *p_ino; + if (ino->dentry) { ino->dentry->d_fsdata = NULL; - if (ino->dentry->d_inode) + if (ino->dentry->d_inode) { + struct dentry *parent = ino->dentry->d_parent; + if (atomic_dec_and_test(&ino->count)) { + p_ino = autofs4_dentry_ino(parent); + if (p_ino && parent != ino->dentry) + atomic_dec(&p_ino->count); + } dput(ino->dentry); + } ino->dentry = NULL; } if (ino->free) @@ -85,9 +101,12 @@ void autofs4_free_ino(struct autofs_info */ static void autofs4_force_release(struct autofs_sb_info *sbi) { - struct dentry *this_parent = sbi->root; + struct dentry *this_parent = sbi->sb->s_root; struct list_head *next; + if (!sbi->sb->s_root) + return; + spin_lock(&dcache_lock); repeat: next = this_parent->d_subdirs.next; @@ -116,7 +135,7 @@ resume: spin_lock(&dcache_lock); } - if (this_parent != sbi->root) { + if (this_parent != sbi->sb->s_root) { struct dentry *dentry = this_parent; next = this_parent->d_child.next; @@ -129,38 +148,66 @@ resume: goto resume; } spin_unlock(&dcache_lock); - - dput(sbi->root); - sbi->root = NULL; shrink_dcache_sb(sbi->sb); - - return; } -static void autofs4_put_super(struct super_block *sb) +void autofs4_kill_sb(struct super_block *sb) { struct autofs_sb_info *sbi = autofs4_sbi(sb); - sb->s_fs_info = NULL; + /* + * In the event of a failure in get_sb_nodev the superblock + * info is not present so nothing else has been setup, so + * just call kill_anon_super when we are called from + * deactivate_super. + */ + if (!sbi) + goto out_kill_sb; - if ( !sbi->catatonic ) - autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */ + /* Free wait queues, close pipe */ + autofs4_catatonic_mode(sbi); /* Clean up and release dangling references */ - if (sbi) - autofs4_force_release(sbi); + autofs4_force_release(sbi); + sb->s_fs_info = NULL; kfree(sbi); +out_kill_sb: DPRINTK("shutting down"); + kill_anon_super(sb); +} + +static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt) +{ + struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb); + + if (!sbi) + return 0; + + seq_printf(m, ",fd=%d", sbi->pipefd); + seq_printf(m, ",pgrp=%d", sbi->oz_pgrp); + seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); + seq_printf(m, ",minproto=%d", sbi->min_proto); + seq_printf(m, ",maxproto=%d", sbi->max_proto); + + if (sbi->type & AUTOFS_TYPE_OFFSET) + seq_printf(m, ",offset"); + else if (sbi->type & AUTOFS_TYPE_DIRECT) + seq_printf(m, ",direct"); + else + seq_printf(m, ",indirect"); + + return 0; } static struct super_operations autofs4_sops = { - .put_super = autofs4_put_super, .statfs = simple_statfs, + .show_options = autofs4_show_options, }; -enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto}; +enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto, + Opt_indirect, Opt_direct, Opt_offset}; static match_table_t tokens = { {Opt_fd, "fd=%u"}, @@ -169,11 +216,15 @@ static match_table_t tokens = { {Opt_pgrp, "pgrp=%u"}, {Opt_minproto, "minproto=%u"}, {Opt_maxproto, "maxproto=%u"}, + {Opt_indirect, "indirect"}, + {Opt_direct, "direct"}, + {Opt_offset, "offset"}, {Opt_err, NULL} }; static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, - pid_t *pgrp, int *minproto, int *maxproto) + pid_t *pgrp, unsigned int *type, + int *minproto, int *maxproto) { char *p; substring_t args[MAX_OPT_ARGS]; @@ -227,6 +278,15 @@ static int parse_options(char *options, return 1; *maxproto = option; break; + case Opt_indirect: + *type = AUTOFS_TYPE_INDIRECT; + break; + case Opt_direct: + *type = AUTOFS_TYPE_DIRECT; + break; + case Opt_offset: + *type = AUTOFS_TYPE_OFFSET; + break; default: return 1; } @@ -245,6 +305,10 @@ static struct autofs_info *autofs4_mkroo return ino; } +static struct dentry_operations autofs4_sb_dentry_operations = { + .d_release = autofs4_dentry_release, +}; + int autofs4_fill_super(struct super_block *s, void *data, int silent) { struct inode * root_inode; @@ -253,7 +317,6 @@ int autofs4_fill_super(struct super_bloc int pipefd; struct autofs_sb_info *sbi; struct autofs_info *ino; - int minproto, maxproto; sbi = (struct autofs_sb_info *) kmalloc(sizeof(*sbi), GFP_KERNEL); if ( !sbi ) @@ -264,16 +327,23 @@ int autofs4_fill_super(struct super_bloc s->s_fs_info = sbi; sbi->magic = AUTOFS_SBI_MAGIC; - sbi->root = NULL; - sbi->catatonic = 0; + sbi->pipefd = -1; + sbi->pipe = NULL; + sbi->catatonic = 1; sbi->exp_timeout = 0; sbi->oz_pgrp = process_group(current); sbi->sb = s; sbi->version = 0; sbi->sub_version = 0; + sbi->type = AUTOFS_TYPE_INDIRECT; + sbi->min_proto = 0; + sbi->max_proto = 0; init_MUTEX(&sbi->wq_sem); spin_lock_init(&sbi->fs_lock); sbi->queues = NULL; + spin_lock_init(&sbi->lookup_lock); + INIT_LIST_HEAD(&sbi->active_list); + INIT_LIST_HEAD(&sbi->expiring_list); s->s_blocksize = 1024; s->s_blocksize_bits = 10; s->s_magic = AUTOFS_SUPER_MAGIC; @@ -287,38 +357,46 @@ int autofs4_fill_super(struct super_bloc if (!ino) goto fail_free; root_inode = autofs4_get_inode(s, ino); - kfree(ino); if (!root_inode) - goto fail_free; + goto fail_ino; - root_inode->i_op = &autofs4_root_inode_operations; - root_inode->i_fop = &autofs4_root_operations; root = d_alloc_root(root_inode); - pipe = NULL; - if (!root) goto fail_iput; + pipe = NULL; + + root->d_op = &autofs4_sb_dentry_operations; + root->d_fsdata = ino; /* Can this call block? */ if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid, - &sbi->oz_pgrp, - &minproto, &maxproto)) { + &sbi->oz_pgrp, &sbi->type, + &sbi->min_proto, &sbi->max_proto)) { printk("autofs: called with bogus options\n"); goto fail_dput; } + root_inode->i_fop = &autofs4_root_operations; + root_inode->i_op = sbi->type & AUTOFS_TYPE_TRIGGER ? + &autofs4_direct_root_inode_operations : + &autofs4_indirect_root_inode_operations; + /* Couldn't this be tested earlier? */ - if (maxproto < AUTOFS_MIN_PROTO_VERSION || - minproto > AUTOFS_MAX_PROTO_VERSION) { + if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION || + sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) { printk("autofs: kernel does not match daemon version " "daemon (%d, %d) kernel (%d, %d)\n", - minproto, maxproto, + sbi->min_proto, sbi->max_proto, AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION); goto fail_dput; } - sbi->version = maxproto > AUTOFS_MAX_PROTO_VERSION ? AUTOFS_MAX_PROTO_VERSION : maxproto; + /* Establish highest kernel protocol version */ + if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION) + sbi->version = AUTOFS_MAX_PROTO_VERSION; + else + sbi->version = sbi->max_proto; sbi->sub_version = AUTOFS_PROTO_SUBVERSION; DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp); @@ -331,13 +409,8 @@ int autofs4_fill_super(struct super_bloc if ( !pipe->f_op || !pipe->f_op->write ) goto fail_fput; sbi->pipe = pipe; - - /* - * Take a reference to the root dentry so we get a chance to - * clean up the dentry tree on umount. - * See autofs4_force_release. - */ - sbi->root = dget(root); + sbi->pipefd = pipefd; + sbi->catatonic = 0; /* * Success! Install the root dentry now to indicate completion. @@ -358,8 +431,11 @@ fail_dput: fail_iput: printk("autofs: get root dentry failed\n"); iput(root_inode); +fail_ino: + kfree(ino); fail_free: kfree(sbi); + s->s_fs_info = NULL; fail_unlock: return -EINVAL; } Index: linux-2.6.13/fs/autofs4/waitq.c =================================================================== --- linux-2.6.13/fs/autofs4/waitq.c +++ linux-2.6.13/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 @@ -28,24 +28,31 @@ void autofs4_catatonic_mode(struct autof { struct autofs_wait_queue *wq, *nwq; + down(&sbi->wq_sem); + if (sbi->catatonic) { + up(&sbi->wq_sem); + return; + } + DPRINTK("entering catatonic mode"); 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); - wq->name = NULL; + if (wq->name.name) { + kfree(wq->name.name); + wq->name.name = NULL; + } + wq->wait_ctr--; wake_up_interruptible(&wq->queue); wq = nwq; } - if (sbi->pipe) { - fput(sbi->pipe); /* Close the pipe */ - sbi->pipe = NULL; - } - + fput(sbi->pipe); /* Close the pipe */ + sbi->pipe = NULL; + up(&sbi->wq_sem); shrink_dcache_sb(sbi->sb); } @@ -88,41 +95,90 @@ static void autofs4_notify_daemon(struct 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; + struct file *pipe = NULL; size_t pktsz; DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d", - wq->wait_queue_token, wq->len, wq->name, type); + wq->wait_queue_token, wq->name.len, wq->name.name, type); memset(&pkt,0,sizeof pkt); /* For security reasons */ 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); mp->wait_queue_token = wq->wait_queue_token; - 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; + mp->len = wq->name.len; + memcpy(mp->name, wq->name.name, wq->name.len); + mp->name[wq->name.len] = '\0'; + break; + } + case autofs_ptype_expire_multi: + { + struct autofs_packet_expire_multi *ep = &pkt.v4_pkt.expire_multi; pktsz = sizeof(*ep); ep->wait_queue_token = wq->wait_queue_token; - ep->len = wq->len; - memcpy(ep->name, wq->name, wq->len); - ep->name[wq->len] = '\0'; - } else { + ep->len = wq->name.len; + memcpy(ep->name, wq->name.name, wq->name.len); + ep->name[wq->name.len] = '\0'; + 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->name.len; + memcpy(packet->name, wq->name.name, wq->name.len); + packet->name[wq->name.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; } - if (autofs4_write(sbi->pipe, &pkt, pktsz)) - autofs4_catatonic_mode(sbi); + /* Check if we have become catatonic */ + down(&sbi->wq_sem); + if (!sbi->catatonic) { + pipe = sbi->pipe; + get_file(pipe); + } + up(&sbi->wq_sem); + + if (pipe) { + if (autofs4_write(pipe, &pkt, pktsz)) + autofs4_catatonic_mode(sbi); + fput(pipe); + } } static int autofs4_getpath(struct autofs_sb_info *sbi, @@ -138,7 +194,7 @@ static int autofs4_getpath(struct autofs for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent) len += tmp->d_name.len + 1; - if (--len > NAME_MAX) { + if (!len || --len > NAME_MAX) { spin_unlock(&dcache_lock); return 0; } @@ -157,51 +213,170 @@ static int autofs4_getpath(struct autofs return len; } +static struct autofs_wait_queue * +autofs4_find_wait(struct autofs_sb_info *sbi, struct qstr *qstr) +{ + struct autofs_wait_queue *wq = NULL; + + for (wq = sbi->queues ; wq ; wq = wq->next) { + if (wq->name.hash == qstr->hash && + wq->name.len == qstr->len && + wq->name.name && !memcmp(wq->name.name, qstr->name, qstr->len)) + break; + } + return wq; +} + +/* + * Check if we have a valid request. + * Returns + * 1 if the request should continue. + * In this case we can return an autofs_wait_queue entry if one is + * found or NULL to idicate a new wait needs to be created. + * 0 or a negative errno if the request shouldn't continue. + */ +static int validate_request(struct autofs_wait_queue **wait, + struct autofs_sb_info *sbi, + struct qstr *qstr, + struct dentry*dentry, enum autofs_notify notify) +{ + struct autofs_wait_queue *wq; + struct autofs_info *ino; + + /* Wait in progress, continue; */ + wq = autofs4_find_wait(sbi, qstr); + if (wq) { + *wait = wq; + return 1; + } + + *wait = NULL; + + /* If we don't yet have any info this is a new request */ + ino = autofs4_dentry_ino(dentry); + if (!ino) + return 1; + + /* + * If we've been asked to wait on an existing expire (NFY_NONE) + * but there is no wait in the queue ... + */ + if (notify == NFY_NONE) { + /* + * Either we've betean the pending expire to post it's + * wait or it finished while we waited on the semaphore. + * So we need to wait till either, the wait appears + * or the expire finishes. + */ + + while (ino->flags & AUTOFS_INF_EXPIRING) { + up(&sbi->wq_sem); + set_current_state(TASK_INTERRUPTIBLE);schedule_timeout(HZ/10); + if (down_interruptible(&sbi->wq_sem)) + return -EINTR; + + wq = autofs4_find_wait(sbi, qstr); + if (wq) { + *wait = wq; + return 1; + } + } + + /* + * 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. + */ + return 0; + } + + /* + * If we've been asked to trigger a mount and the request + * completed while we waited on the semaphore ... + */ + if (notify == NFY_MOUNT) { + /* + * If the dentry isn't hashed just go ahead and try the + * mount again with a new wait (not much else we can do). + */ + if (!d_unhashed(dentry)) { + /* + * But if the dentry is hashed, that means that we + * got here through the revalidate path. Thus, we + * need to check if the dentry has been mounted + * while we waited on the wq_semaphore. If it has, + * simply return success. + */ + if (d_mountpoint(dentry)) + return 0; + } + } + + return 1; +} + int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, enum autofs_notify notify) { struct autofs_wait_queue *wq; + struct qstr qstr; char *name; - int len, status; + int status, ret, type; /* In catatonic mode, we don't wait for nobody */ - if ( sbi->catatonic ) + if (sbi->catatonic) return -ENOENT; - + + if (!dentry->d_inode) { + /* + * A wait for a negative dentry is invalid for certain + * cases. A direct or offset mount "always" has its mount + * point directory created and so the request dentry must + * be positive or the map key doesn't exist. The situation + * is very similar for indirect mounts except only dentrys + * in the root of the autofs file system may be negative. + */ + if (sbi->type & AUTOFS_TYPE_TRIGGER) + return -ENOENT; + else if (!IS_ROOT(dentry->d_parent)) + 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_TRIGGER) + qstr.len = sprintf(name, "%p", dentry); + else { + qstr.len = autofs4_getpath(sbi, dentry, &name); + if (!qstr.len) { + kfree(name); + return -ENOENT; + } } + qstr.name = name; + qstr.hash = full_name_hash(name, qstr.len); if (down_interruptible(&sbi->wq_sem)) { - kfree(name); + kfree(qstr.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; - } - - if ( !wq ) { - /* Can't wait for an expire if there's no mount */ - if (notify == NFY_NONE && !d_mountpoint(dentry)) { - kfree(name); + ret = validate_request(&wq, sbi, &qstr, dentry, notify); + if (ret <= 0) { + if (ret == 0) up(&sbi->wq_sem); - return -ENOENT; - } + kfree(qstr.name); + return ret; + } + if (!wq) { /* Create a new wait queue */ wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL); - if ( !wq ) { - kfree(name); + if (!wq) { + kfree(qstr.name); up(&sbi->wq_sem); return -ENOMEM; } @@ -212,44 +387,53 @@ int autofs4_wait(struct autofs_sb_info * wq->next = sbi->queues; sbi->queues = wq; init_waitqueue_head(&wq->queue); - wq->hash = dentry->d_name.hash; - wq->name = name; - wq->len = len; + memcpy(&wq->name, &qstr, sizeof(struct qstr)); + 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); + wq->wait_ctr = 2; 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); + 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_TRIGGER) ? + autofs_ptype_missing_direct : + autofs_ptype_missing_indirect; + else + type = (sbi->type & AUTOFS_TYPE_TRIGGER) ? + 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); + (unsigned long) wq->wait_queue_token, wq->name.len, + wq->name.name, notify); /* autofs4_notify_daemon() may block */ autofs4_notify_daemon(sbi, wq, type); + } else { + wq->wait_ctr++; + up(&sbi->wq_sem); + kfree(qstr.name); + DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d", + (unsigned long) wq->wait_queue_token, wq->name.len, + wq->name.name, notify); } - /* wq->name is NULL if and only if the lock is already released */ - - if ( sbi->catatonic ) { - /* We might have slept, so check again for catatonic mode */ - wq->status = -ENOENT; - if ( wq->name ) { - kfree(wq->name); - wq->name = NULL; - } - } - - if ( wq->name ) { + /* + * wq->name.name is NULL iff the lock is already released + * or the mount has been made catatonic. + */ + if (wq->name.name) { /* Block all but "shutdown" signals while waiting */ sigset_t oldset; unsigned long irqflags; @@ -260,7 +444,7 @@ int autofs4_wait(struct autofs_sb_info * recalc_sigpending(); spin_unlock_irqrestore(¤t->sighand->siglock, irqflags); - wait_event_interruptible(wq->queue, wq->name == NULL); + wait_event_interruptible(wq->queue, wq->name.name == NULL); spin_lock_irqsave(¤t->sighand->siglock, irqflags); current->blocked = oldset; @@ -273,8 +457,10 @@ int autofs4_wait(struct autofs_sb_info * status = wq->status; /* Are we the last process to need status? */ - if (atomic_dec_and_test(&wq->wait_ctr)) + down(&sbi->wq_sem); + if (!--wq->wait_ctr) kfree(wq); + up(&sbi->wq_sem); return status; } @@ -285,27 +471,24 @@ int autofs4_wait_release(struct autofs_s 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 ) + for (wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next) { + if (wq->wait_queue_token == wait_queue_token) break; } - if ( !wq ) { + if (!wq) { up(&sbi->wq_sem); return -EINVAL; } *wql = wq->next; /* Unlink from chain */ - up(&sbi->wq_sem); - kfree(wq->name); - wq->name = NULL; /* Do not wait on this queue */ - + kfree(wq->name.name); + wq->name.name = NULL; /* Do not wait on this queue */ wq->status = status; - - if (atomic_dec_and_test(&wq->wait_ctr)) /* Is anyone still waiting for this guy? */ + wake_up_interruptible(&wq->queue); + if (!--wq->wait_ctr) kfree(wq); - else - wake_up_interruptible(&wq->queue); + up(&sbi->wq_sem); return 0; } Index: linux-2.6.13/fs/autofs/dirhash.c =================================================================== --- linux-2.6.13/fs/autofs/dirhash.c +++ linux-2.6.13/fs/autofs/dirhash.c @@ -92,7 +92,7 @@ struct autofs_dir_ent *autofs_expire(str ; dput(dentry); - if ( may_umount(mnt) == 0 ) { + if ( may_umount(mnt) ) { mntput(mnt); DPRINTK(("autofs: signaling expire on %s\n", ent->name)); return ent; /* Expirable! */ Index: linux-2.6.13/fs/namespace.c =================================================================== --- linux-2.6.13/fs/namespace.c +++ linux-2.6.13/fs/namespace.c @@ -308,9 +308,9 @@ resume: spin_unlock(&vfsmount_lock); if (actual_refs > minimum_refs) - return -EBUSY; + return 0; - return 0; + return 1; } EXPORT_SYMBOL(may_umount_tree); @@ -330,9 +330,10 @@ EXPORT_SYMBOL(may_umount_tree); */ int may_umount(struct vfsmount *mnt) { + int ret = 1; if (atomic_read(&mnt->mnt_count) > 2) - return -EBUSY; - return 0; + ret = 0; + return ret; } EXPORT_SYMBOL(may_umount); Index: linux-2.6.13/include/linux/auto_fs4.h =================================================================== --- linux-2.6.13/include/linux/auto_fs4.h +++ linux-2.6.13/include/linux/auto_fs4.h @@ -19,18 +19,42 @@ #undef AUTOFS_MIN_PROTO_VERSION #undef AUTOFS_MAX_PROTO_VERSION -#define AUTOFS_PROTO_VERSION 4 +#define AUTOFS_PROTO_VERSION 5 #define AUTOFS_MIN_PROTO_VERSION 3 -#define AUTOFS_MAX_PROTO_VERSION 4 +#define AUTOFS_MAX_PROTO_VERSION 5 -#define AUTOFS_PROTO_SUBVERSION 7 +#define AUTOFS_PROTO_SUBVERSION 0 /* Mask for expire behaviour */ #define AUTOFS_EXP_IMMEDIATE 1 #define AUTOFS_EXP_LEAVES 2 -/* New message type */ -#define autofs_ptype_expire_multi 2 /* Expire entry (umount request) */ +#define AUTOFS_TYPE_ANY 0x0000 +#define AUTOFS_TYPE_INDIRECT 0x0001 +#define AUTOFS_TYPE_DIRECT 0x0002 +#define AUTOFS_TYPE_OFFSET 0x0004 + +/* Daemon notification packet types */ +enum autofs_notify { + NFY_NONE, + NFY_MOUNT, + NFY_EXPIRE +}; + +/* Kernel protocol version 4 packet types */ + +/* Expire entry (umount request) */ +#define autofs_ptype_expire_multi 2 + +/* Kernel protocol version 5 packet types */ + +/* Indirect mount missing and expire requests. */ +#define autofs_ptype_missing_indirect 3 +#define autofs_ptype_expire_indirect 4 + +/* Direct mount missing and expire requests */ +#define autofs_ptype_missing_direct 5 +#define autofs_ptype_expire_direct 6 /* v4 multi expire (via pipe) */ struct autofs_packet_expire_multi { @@ -47,10 +71,38 @@ union autofs_packet_union { struct autofs_packet_expire_multi expire_multi; }; +/* autofs v5 common packet struct */ +struct autofs_v5_packet { + struct autofs_packet_hdr hdr; + autofs_wqt_t wait_queue_token; + __u32 dev; + __u64 ino; + __u32 uid; + __u32 gid; + __u32 pid; + __u32 tgid; + __u32 len; + char name[NAME_MAX+1]; +}; + +typedef struct autofs_v5_packet autofs_packet_missing_indirect_t; +typedef struct autofs_v5_packet autofs_packet_expire_indirect_t; +typedef struct autofs_v5_packet autofs_packet_missing_direct_t; +typedef struct autofs_v5_packet autofs_packet_expire_direct_t; + +union autofs_v5_packet_union { + struct autofs_packet_hdr hdr; + struct autofs_v5_packet v5_packet; + autofs_packet_missing_indirect_t missing_indirect; + autofs_packet_expire_indirect_t expire_indirect; + autofs_packet_missing_direct_t missing_direct; + autofs_packet_expire_direct_t expire_direct; +}; + #define AUTOFS_IOC_EXPIRE_MULTI _IOW(0x93,0x66,int) +#define AUTOFS_IOC_EXPIRE_INDIRECT AUTOFS_IOC_EXPIRE_MULTI +#define AUTOFS_IOC_EXPIRE_DIRECT AUTOFS_IOC_EXPIRE_MULTI #define AUTOFS_IOC_PROTOSUBVER _IOR(0x93,0x67,int) -#define AUTOFS_IOC_ASKREGHOST _IOR(0x93,0x68,int) -#define AUTOFS_IOC_TOGGLEREGHOST _IOR(0x93,0x69,int) #define AUTOFS_IOC_ASKUMOUNT _IOR(0x93,0x70,int) Index: linux-2.6.13/fs/namei.c =================================================================== --- linux-2.6.13/fs/namei.c +++ linux-2.6.13/fs/namei.c @@ -317,6 +317,29 @@ void path_release_on_umount(struct namei mntput_no_expire(nd->mnt); } +static inline struct dentry *do_revalidate(struct dentry *dentry, struct nameidata *nd) +{ + int status = dentry->d_op->d_revalidate(dentry, nd); + if (unlikely(status <= 0)) { + /* + * The dentry failed validation. + * If d_revalidate returned 0 attempt to invalidate + * the dentry otherwise d_revalidate is asking us + * to return a fail status. + */ + if (!status) { + if (!d_invalidate(dentry)) { + dput(dentry); + dentry = NULL; + } + } else { + dput(dentry); + dentry = ERR_PTR(status); + } + } + return dentry; +} + /* * Internal lookup() using the new generic dcache. * SMP-safe @@ -331,12 +354,9 @@ static struct dentry * cached_lookup(str if (!dentry) dentry = d_lookup(parent, name); - if (dentry && dentry->d_op && dentry->d_op->d_revalidate) { - if (!dentry->d_op->d_revalidate(dentry, nd) && !d_invalidate(dentry)) { - dput(dentry); - dentry = NULL; - } - } + if (dentry && dentry->d_op && dentry->d_op->d_revalidate) + dentry = do_revalidate(dentry, nd); + return dentry; } @@ -429,10 +449,9 @@ static struct dentry * real_lookup(struc */ up(&dir->i_sem); if (result->d_op && result->d_op->d_revalidate) { - if (!result->d_op->d_revalidate(result, nd) && !d_invalidate(result)) { - dput(result); + result = do_revalidate(result, nd); + if (!result) result = ERR_PTR(-ENOENT); - } } return result; } @@ -507,8 +526,15 @@ static inline int __do_follow_link(struc touch_atime(path->mnt, dentry); nd_set_link(nd, NULL); - if (path->mnt == nd->mnt) - mntget(path->mnt); + if (path->mnt != nd->mnt) { + dput(nd->dentry); + if (nd->mnt != path->mnt) + mntput(nd->mnt); + nd->mnt = path->mnt; + nd->dentry = path->dentry; + dget(dentry); + } + mntget(path->mnt); cookie = dentry->d_inode->i_op->follow_link(dentry, nd); error = PTR_ERR(cookie); if (!IS_ERR(cookie)) { @@ -695,12 +721,12 @@ need_lookup: goto done; need_revalidate: - if (dentry->d_op->d_revalidate(dentry, nd)) - goto done; - if (d_invalidate(dentry)) - goto done; - dput(dentry); - goto need_lookup; + dentry = do_revalidate(dentry, nd); + if (!dentry) + goto need_lookup; + if (IS_ERR(dentry)) + goto fail; + goto done; fail: return PTR_ERR(dentry); Index: linux-2.6.13/fs/autofs/init.c =================================================================== --- linux-2.6.13/fs/autofs/init.c +++ linux-2.6.13/fs/autofs/init.c @@ -24,7 +24,7 @@ static struct file_system_type autofs_fs .owner = THIS_MODULE, .name = "autofs", .get_sb = autofs_get_sb, - .kill_sb = kill_anon_super, + .kill_sb = autofs_kill_sb, }; static int __init init_autofs_fs(void) Index: linux-2.6.13/fs/autofs/inode.c =================================================================== --- linux-2.6.13/fs/autofs/inode.c +++ linux-2.6.13/fs/autofs/inode.c @@ -19,11 +19,20 @@ #include "autofs_i.h" #include -static void autofs_put_super(struct super_block *sb) +void autofs4_kill_sb(struct super_block *sb) { struct autofs_sb_info *sbi = autofs_sbi(sb); unsigned int n; + /* + * In the event of a failure in get_sb_nodev the superblock + * info is not present so nothing else has been setup, so + * just call kill_anon_super when we are called from + * deactivate_super. + */ + if (!sbi) + goto out_kill_sb; + if ( !sbi->catatonic ) autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */ @@ -35,14 +44,15 @@ static void autofs_put_super(struct supe kfree(sb->s_fs_info); +out_kill_sb: DPRINTK(("autofs: shutting down\n")); + kill_anon_super(sb); } static void autofs_read_inode(struct inode *inode); static struct super_operations autofs_sops = { .read_inode = autofs_read_inode, - .put_super = autofs_put_super, .statfs = simple_statfs, }; @@ -136,7 +146,8 @@ int autofs_fill_super(struct super_block s->s_fs_info = sbi; sbi->magic = AUTOFS_SBI_MAGIC; - sbi->catatonic = 0; + sbi->pipe = NULL; + sbi->catatonic = 1; sbi->exp_timeout = 0; sbi->oz_pgrp = process_group(current); autofs_initialize_hash(&sbi->dirhash); @@ -179,6 +190,7 @@ int autofs_fill_super(struct super_block if ( !pipe->f_op || !pipe->f_op->write ) goto fail_fput; sbi->pipe = pipe; + sbi->catatonic = 0; /* * Success! Install the root dentry now to indicate completion. @@ -197,6 +209,7 @@ fail_iput: iput(root_inode); fail_free: kfree(sbi); + s->s_fs_info = NULL; fail_unlock: return -EINVAL; } Index: linux-2.6.13/fs/autofs/autofs_i.h =================================================================== --- linux-2.6.13/fs/autofs/autofs_i.h +++ linux-2.6.13/fs/autofs/autofs_i.h @@ -150,6 +150,7 @@ extern struct file_operations autofs_roo /* Initializing function */ int autofs_fill_super(struct super_block *, void *, int); +void autofs_kill_sb(struct super_block *); /* Queue management functions */ Index: linux-2.6.13/fs/autofs4/init.c =================================================================== --- linux-2.6.13/fs/autofs4/init.c +++ linux-2.6.13/fs/autofs4/init.c @@ -24,7 +24,7 @@ static struct file_system_type autofs_fs .owner = THIS_MODULE, .name = "autofs", .get_sb = autofs_get_sb, - .kill_sb = kill_anon_super, + .kill_sb = autofs4_kill_sb, }; static int __init init_autofs4_fs(void) Index: linux-2.6.13/fs/autofs/waitq.c =================================================================== --- linux-2.6.13/fs/autofs/waitq.c +++ linux-2.6.13/fs/autofs/waitq.c @@ -41,6 +41,7 @@ void autofs_catatonic_mode(struct autofs wq = nwq; } fput(sbi->pipe); /* Close the pipe */ + sbi->pipe = NULL; autofs_hash_dputall(&sbi->dirhash); /* Remove all dentry pointers */ } Index: linux-2.6.13/include/linux/compat_ioctl.h =================================================================== --- linux-2.6.13/include/linux/compat_ioctl.h +++ linux-2.6.13/include/linux/compat_ioctl.h @@ -583,8 +583,6 @@ COMPATIBLE_IOCTL(AUTOFS_IOC_PROTOVER) COMPATIBLE_IOCTL(AUTOFS_IOC_EXPIRE) COMPATIBLE_IOCTL(AUTOFS_IOC_EXPIRE_MULTI) COMPATIBLE_IOCTL(AUTOFS_IOC_PROTOSUBVER) -COMPATIBLE_IOCTL(AUTOFS_IOC_ASKREGHOST) -COMPATIBLE_IOCTL(AUTOFS_IOC_TOGGLEREGHOST) COMPATIBLE_IOCTL(AUTOFS_IOC_ASKUMOUNT) /* DEVFS */ COMPATIBLE_IOCTL(DEVFSDIOC_GET_PROTO_REV)