diff options
Diffstat (limited to 'fs/autofs')
| -rw-r--r-- | fs/autofs/Makefile | 7 | ||||
| -rw-r--r-- | fs/autofs/autofs_i.h | 164 | ||||
| -rw-r--r-- | fs/autofs/dirhash.c | 249 | ||||
| -rw-r--r-- | fs/autofs/init.c | 52 | ||||
| -rw-r--r-- | fs/autofs/inode.c | 250 | ||||
| -rw-r--r-- | fs/autofs/root.c | 564 | ||||
| -rw-r--r-- | fs/autofs/symlink.c | 25 | ||||
| -rw-r--r-- | fs/autofs/waitq.c | 206 |
8 files changed, 1517 insertions, 0 deletions
diff --git a/fs/autofs/Makefile b/fs/autofs/Makefile new file mode 100644 index 000000000000..453a60f46d05 --- /dev/null +++ b/fs/autofs/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for the linux autofs-filesystem routines. +# + +obj-$(CONFIG_AUTOFS_FS) += autofs.o + +autofs-objs := dirhash.o init.o inode.o root.o symlink.o waitq.o diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h new file mode 100644 index 000000000000..6171431272dc --- /dev/null +++ b/fs/autofs/autofs_i.h @@ -0,0 +1,164 @@ +/* -*- linux-c -*- ------------------------------------------------------- * + * + * linux/fs/autofs/autofs_i.h + * + * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +/* Internal header file for autofs */ + +#include <linux/auto_fs.h> + +/* This is the range of ioctl() numbers we claim as ours */ +#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY +#define AUTOFS_IOC_COUNT 32 + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/string.h> +#include <linux/wait.h> +#include <linux/dcache.h> +#include <linux/namei.h> +#include <linux/mount.h> +#include <linux/sched.h> + +#include <asm/current.h> +#include <asm/uaccess.h> + +#ifdef DEBUG +#define DPRINTK(D) (printk D) +#else +#define DPRINTK(D) ((void)0) +#endif + +#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 */ + +/* Structures associated with the root directory hash table */ + +#define AUTOFS_HASH_SIZE 67 + +struct autofs_dir_ent { + int hash; + char *name; + int len; + ino_t ino; + struct dentry *dentry; + /* Linked list of entries */ + struct autofs_dir_ent *next; + struct autofs_dir_ent **back; + /* The following entries are for the expiry system */ + unsigned long last_usage; + struct list_head exp; +}; + +struct autofs_dirhash { + struct autofs_dir_ent *h[AUTOFS_HASH_SIZE]; + struct list_head expiry_head; +}; + +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; + /* This is for status reporting upon return */ + int status; + int wait_ctr; +}; + +struct autofs_symlink { + char *data; + int len; + time_t mtime; +}; + +#define AUTOFS_MAX_SYMLINKS 256 + +#define AUTOFS_ROOT_INO 1 +#define AUTOFS_FIRST_SYMLINK 2 +#define AUTOFS_FIRST_DIR_INO (AUTOFS_FIRST_SYMLINK+AUTOFS_MAX_SYMLINKS) + +#define AUTOFS_SYMLINK_BITMAP_LEN \ + ((AUTOFS_MAX_SYMLINKS+((sizeof(long)*1)-1))/(sizeof(long)*8)) + +#define AUTOFS_SBI_MAGIC 0x6d4a556d + +struct autofs_sb_info { + u32 magic; + struct file *pipe; + pid_t oz_pgrp; + int catatonic; + unsigned long exp_timeout; + ino_t next_dir_ino; + struct autofs_wait_queue *queues; /* Wait queue pointer */ + struct autofs_dirhash dirhash; /* Root directory hash */ + struct autofs_symlink symlink[AUTOFS_MAX_SYMLINKS]; + unsigned long symlink_bitmap[AUTOFS_SYMLINK_BITMAP_LEN]; +}; + +static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb) +{ + return (struct autofs_sb_info *)(sb->s_fs_info); +} + +/* autofs_oz_mode(): do we see the man behind the curtain? (The + processes which do manipulations for us in user space sees the raw + filesystem without "magic".) */ + +static inline int autofs_oz_mode(struct autofs_sb_info *sbi) { + return sbi->catatonic || process_group(current) == sbi->oz_pgrp; +} + +/* Hash operations */ + +void autofs_initialize_hash(struct autofs_dirhash *); +struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *,struct qstr *); +void autofs_hash_insert(struct autofs_dirhash *,struct autofs_dir_ent *); +void autofs_hash_delete(struct autofs_dir_ent *); +struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *,off_t *,struct autofs_dir_ent *); +void autofs_hash_dputall(struct autofs_dirhash *); +void autofs_hash_nuke(struct autofs_dirhash *); + +/* Expiration-handling functions */ + +void autofs_update_usage(struct autofs_dirhash *,struct autofs_dir_ent *); +struct autofs_dir_ent *autofs_expire(struct super_block *,struct autofs_sb_info *, struct vfsmount *mnt); + +/* Operations structures */ + +extern struct inode_operations autofs_root_inode_operations; +extern struct inode_operations autofs_symlink_inode_operations; +extern struct file_operations autofs_root_operations; + +/* Initializing function */ + +int autofs_fill_super(struct super_block *, void *, int); + +/* Queue management functions */ + +int autofs_wait(struct autofs_sb_info *,struct qstr *); +int autofs_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); +void autofs_catatonic_mode(struct autofs_sb_info *); + +#ifdef DEBUG +void autofs_say(const char *name, int len); +#else +#define autofs_say(n,l) ((void)0) +#endif diff --git a/fs/autofs/dirhash.c b/fs/autofs/dirhash.c new file mode 100644 index 000000000000..448143fd0796 --- /dev/null +++ b/fs/autofs/dirhash.c @@ -0,0 +1,249 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/dirhash.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include "autofs_i.h" + +/* Functions for maintenance of expiry queue */ + +static void autofs_init_usage(struct autofs_dirhash *dh, + struct autofs_dir_ent *ent) +{ + list_add_tail(&ent->exp, &dh->expiry_head); + ent->last_usage = jiffies; +} + +static void autofs_delete_usage(struct autofs_dir_ent *ent) +{ + list_del(&ent->exp); +} + +void autofs_update_usage(struct autofs_dirhash *dh, + struct autofs_dir_ent *ent) +{ + autofs_delete_usage(ent); /* Unlink from current position */ + autofs_init_usage(dh,ent); /* Relink at queue tail */ +} + +struct autofs_dir_ent *autofs_expire(struct super_block *sb, + struct autofs_sb_info *sbi, + struct vfsmount *mnt) +{ + struct autofs_dirhash *dh = &sbi->dirhash; + struct autofs_dir_ent *ent; + struct dentry *dentry; + unsigned long timeout = sbi->exp_timeout; + + while (1) { + if ( list_empty(&dh->expiry_head) || sbi->catatonic ) + return NULL; /* No entries */ + /* We keep the list sorted by last_usage and want old stuff */ + ent = list_entry(dh->expiry_head.next, struct autofs_dir_ent, exp); + if (jiffies - ent->last_usage < timeout) + break; + /* Move to end of list in case expiry isn't desirable */ + autofs_update_usage(dh, ent); + + /* Check to see that entry is expirable */ + if ( ent->ino < AUTOFS_FIRST_DIR_INO ) + return ent; /* Symlinks are always expirable */ + + /* Get the dentry for the autofs subdirectory */ + dentry = ent->dentry; + + if ( !dentry ) { + /* Should only happen in catatonic mode */ + printk("autofs: dentry == NULL but inode range is directory, entry %s\n", ent->name); + autofs_delete_usage(ent); + continue; + } + + if ( !dentry->d_inode ) { + dput(dentry); + printk("autofs: negative dentry on expiry queue: %s\n", + ent->name); + autofs_delete_usage(ent); + continue; + } + + /* Make sure entry is mounted and unused; note that dentry will + point to the mounted-on-top root. */ + if (!S_ISDIR(dentry->d_inode->i_mode)||!d_mountpoint(dentry)) { + DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name)); + continue; + } + mntget(mnt); + dget(dentry); + if (!follow_down(&mnt, &dentry)) { + dput(dentry); + mntput(mnt); + DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name)); + continue; + } + while (d_mountpoint(dentry) && follow_down(&mnt, &dentry)) + ; + dput(dentry); + + if ( may_umount(mnt) == 0 ) { + mntput(mnt); + DPRINTK(("autofs: signaling expire on %s\n", ent->name)); + return ent; /* Expirable! */ + } + DPRINTK(("autofs: didn't expire due to may_umount: %s\n", ent->name)); + mntput(mnt); + } + return NULL; /* No expirable entries */ +} + +void autofs_initialize_hash(struct autofs_dirhash *dh) { + memset(&dh->h, 0, AUTOFS_HASH_SIZE*sizeof(struct autofs_dir_ent *)); + INIT_LIST_HEAD(&dh->expiry_head); +} + +struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *dh, struct qstr *name) +{ + struct autofs_dir_ent *dhn; + + DPRINTK(("autofs_hash_lookup: hash = 0x%08x, name = ", name->hash)); + autofs_say(name->name,name->len); + + for ( dhn = dh->h[(unsigned) name->hash % AUTOFS_HASH_SIZE] ; dhn ; dhn = dhn->next ) { + if ( name->hash == dhn->hash && + name->len == dhn->len && + !memcmp(name->name, dhn->name, name->len) ) + break; + } + + return dhn; +} + +void autofs_hash_insert(struct autofs_dirhash *dh, struct autofs_dir_ent *ent) +{ + struct autofs_dir_ent **dhnp; + + DPRINTK(("autofs_hash_insert: hash = 0x%08x, name = ", ent->hash)); + autofs_say(ent->name,ent->len); + + autofs_init_usage(dh,ent); + if (ent->dentry) + dget(ent->dentry); + + dhnp = &dh->h[(unsigned) ent->hash % AUTOFS_HASH_SIZE]; + ent->next = *dhnp; + ent->back = dhnp; + *dhnp = ent; + if ( ent->next ) + ent->next->back = &(ent->next); +} + +void autofs_hash_delete(struct autofs_dir_ent *ent) +{ + *(ent->back) = ent->next; + if ( ent->next ) + ent->next->back = ent->back; + + autofs_delete_usage(ent); + + if ( ent->dentry ) + dput(ent->dentry); + kfree(ent->name); + kfree(ent); +} + +/* + * Used by readdir(). We must validate "ptr", so we can't simply make it + * a pointer. Values below 0xffff are reserved; calling with any value + * <= 0x10000 will return the first entry found. + * + * "last" can be NULL or the value returned by the last search *if* we + * want the next sequential entry. + */ +struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *dh, + off_t *ptr, struct autofs_dir_ent *last) +{ + int bucket, ecount, i; + struct autofs_dir_ent *ent; + + bucket = (*ptr >> 16) - 1; + ecount = *ptr & 0xffff; + + if ( bucket < 0 ) { + bucket = ecount = 0; + } + + DPRINTK(("autofs_hash_enum: bucket %d, entry %d\n", bucket, ecount)); + + ent = last ? last->next : NULL; + + if ( ent ) { + ecount++; + } else { + while ( bucket < AUTOFS_HASH_SIZE ) { + ent = dh->h[bucket]; + for ( i = ecount ; ent && i ; i-- ) + ent = ent->next; + + if (ent) { + ecount++; /* Point to *next* entry */ + break; + } + + bucket++; ecount = 0; + } + } + +#ifdef DEBUG + if ( !ent ) + printk("autofs_hash_enum: nothing found\n"); + else { + printk("autofs_hash_enum: found hash %08x, name", ent->hash); + autofs_say(ent->name,ent->len); + } +#endif + + *ptr = ((bucket+1) << 16) + ecount; + return ent; +} + +/* Iterate over all the ents, and remove all dentry pointers. Used on + entering catatonic mode, in order to make the filesystem unmountable. */ +void autofs_hash_dputall(struct autofs_dirhash *dh) +{ + int i; + struct autofs_dir_ent *ent; + + for ( i = 0 ; i < AUTOFS_HASH_SIZE ; i++ ) { + for ( ent = dh->h[i] ; ent ; ent = ent->next ) { + if ( ent->dentry ) { + dput(ent->dentry); + ent->dentry = NULL; + } + } + } +} + +/* Delete everything. This is used on filesystem destruction, so we + make no attempt to keep the pointers valid */ +void autofs_hash_nuke(struct autofs_dirhash *dh) +{ + int i; + struct autofs_dir_ent *ent, *nent; + + for ( i = 0 ; i < AUTOFS_HASH_SIZE ; i++ ) { + for ( ent = dh->h[i] ; ent ; ent = nent ) { + nent = ent->next; + if ( ent->dentry ) + dput(ent->dentry); + kfree(ent->name); + kfree(ent); + } + } +} diff --git a/fs/autofs/init.c b/fs/autofs/init.c new file mode 100644 index 000000000000..b977ece69f0c --- /dev/null +++ b/fs/autofs/init.c @@ -0,0 +1,52 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/init.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include <linux/module.h> +#include <linux/init.h> +#include "autofs_i.h" + +static struct super_block *autofs_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return get_sb_nodev(fs_type, flags, data, autofs_fill_super); +} + +static struct file_system_type autofs_fs_type = { + .owner = THIS_MODULE, + .name = "autofs", + .get_sb = autofs_get_sb, + .kill_sb = kill_anon_super, +}; + +static int __init init_autofs_fs(void) +{ + return register_filesystem(&autofs_fs_type); +} + +static void __exit exit_autofs_fs(void) +{ + unregister_filesystem(&autofs_fs_type); +} + +module_init(init_autofs_fs); +module_exit(exit_autofs_fs); + +#ifdef DEBUG +void autofs_say(const char *name, int len) +{ + printk("(%d: ", len); + while ( len-- ) + printk("%c", *name++); + printk(")\n"); +} +#endif +MODULE_LICENSE("GPL"); diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c new file mode 100644 index 000000000000..4888c1fabbf7 --- /dev/null +++ b/fs/autofs/inode.c @@ -0,0 +1,250 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/inode.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/file.h> +#include <linux/parser.h> +#include <linux/bitops.h> +#include "autofs_i.h" +#include <linux/module.h> + +static void autofs_put_super(struct super_block *sb) +{ + struct autofs_sb_info *sbi = autofs_sbi(sb); + unsigned int n; + + if ( !sbi->catatonic ) + autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */ + + autofs_hash_nuke(&sbi->dirhash); + for ( n = 0 ; n < AUTOFS_MAX_SYMLINKS ; n++ ) { + if ( test_bit(n, sbi->symlink_bitmap) ) + kfree(sbi->symlink[n].data); + } + + kfree(sb->s_fs_info); + + DPRINTK(("autofs: shutting down\n")); +} + +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, +}; + +enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto}; + +static match_table_t autofs_tokens = { + {Opt_fd, "fd=%u"}, + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_pgrp, "pgrp=%u"}, + {Opt_minproto, "minproto=%u"}, + {Opt_maxproto, "maxproto=%u"}, + {Opt_err, NULL} +}; + +static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, pid_t *pgrp, int *minproto, int *maxproto) +{ + char *p; + substring_t args[MAX_OPT_ARGS]; + int option; + + *uid = current->uid; + *gid = current->gid; + *pgrp = process_group(current); + + *minproto = *maxproto = AUTOFS_PROTO_VERSION; + + *pipefd = -1; + + if (!options) + return 1; + + while ((p = strsep(&options, ",")) != NULL) { + int token; + if (!*p) + continue; + + token = match_token(p, autofs_tokens, args); + switch (token) { + case Opt_fd: + if (match_int(&args[0], &option)) + return 1; + *pipefd = option; + break; + case Opt_uid: + if (match_int(&args[0], &option)) + return 1; + *uid = option; + break; + case Opt_gid: + if (match_int(&args[0], &option)) + return 1; + *gid = option; + break; + case Opt_pgrp: + if (match_int(&args[0], &option)) + return 1; + *pgrp = option; + break; + case Opt_minproto: + if (match_int(&args[0], &option)) + return 1; + *minproto = option; + break; + case Opt_maxproto: + if (match_int(&args[0], &option)) + return 1; + *maxproto = option; + break; + default: + return 1; + } + } + return (*pipefd < 0); +} + +int autofs_fill_super(struct super_block *s, void *data, int silent) +{ + struct inode * root_inode; + struct dentry * root; + struct file * pipe; + int pipefd; + struct autofs_sb_info *sbi; + int minproto, maxproto; + + sbi = kmalloc(sizeof(*sbi), GFP_KERNEL); + if ( !sbi ) + goto fail_unlock; + memset(sbi, 0, sizeof(*sbi)); + DPRINTK(("autofs: starting up, sbi = %p\n",sbi)); + + s->s_fs_info = sbi; + sbi->magic = AUTOFS_SBI_MAGIC; + sbi->catatonic = 0; + sbi->exp_timeout = 0; + sbi->oz_pgrp = process_group(current); + autofs_initialize_hash(&sbi->dirhash); + sbi->queues = NULL; + memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN); + sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO; + s->s_blocksize = 1024; + s->s_blocksize_bits = 10; + s->s_magic = AUTOFS_SUPER_MAGIC; + s->s_op = &autofs_sops; + s->s_time_gran = 1; + + root_inode = iget(s, AUTOFS_ROOT_INO); + root = d_alloc_root(root_inode); + pipe = NULL; + + if (!root) + goto fail_iput; + + /* Can this call block? - WTF cares? s is locked. */ + if ( parse_options(data,&pipefd,&root_inode->i_uid,&root_inode->i_gid,&sbi->oz_pgrp,&minproto,&maxproto) ) { + printk("autofs: called with bogus options\n"); + goto fail_dput; + } + + /* Couldn't this be tested earlier? */ + if ( minproto > AUTOFS_PROTO_VERSION || + maxproto < AUTOFS_PROTO_VERSION ) { + printk("autofs: kernel does not match daemon version\n"); + goto fail_dput; + } + + DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, sbi->oz_pgrp)); + pipe = fget(pipefd); + + if ( !pipe ) { + printk("autofs: could not open pipe file descriptor\n"); + goto fail_dput; + } + if ( !pipe->f_op || !pipe->f_op->write ) + goto fail_fput; + sbi->pipe = pipe; + + /* + * Success! Install the root dentry now to indicate completion. + */ + s->s_root = root; + return 0; + +fail_fput: + printk("autofs: pipe file descriptor does not contain proper ops\n"); + fput(pipe); +fail_dput: + dput(root); + goto fail_free; +fail_iput: + printk("autofs: get root dentry failed\n"); + iput(root_inode); +fail_free: + kfree(sbi); +fail_unlock: + return -EINVAL; +} + +static void autofs_read_inode(struct inode *inode) +{ + ino_t ino = inode->i_ino; + unsigned int n; + struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb); + + /* Initialize to the default case (stub directory) */ + + inode->i_op = &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO; + inode->i_nlink = 2; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + inode->i_blocks = 0; + inode->i_blksize = 1024; + + if ( ino == AUTOFS_ROOT_INO ) { + inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR; + inode->i_op = &autofs_root_inode_operations; + inode->i_fop = &autofs_root_operations; + inode->i_uid = inode->i_gid = 0; /* Changed in read_super */ + return; + } + + inode->i_uid = inode->i_sb->s_root->d_inode->i_uid; + inode->i_gid = inode->i_sb->s_root->d_inode->i_gid; + + if ( ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO ) { + /* Symlink inode - should be in symlink list */ + struct autofs_symlink *sl; + + n = ino - AUTOFS_FIRST_SYMLINK; + if ( n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) { + printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino); + return; + } + + inode->i_op = &autofs_symlink_inode_operations; + sl = &sbi->symlink[n]; + inode->u.generic_ip = sl; + inode->i_mode = S_IFLNK | S_IRWXUGO; + inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime; + inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0; + inode->i_size = sl->len; + inode->i_nlink = 1; + } +} diff --git a/fs/autofs/root.c b/fs/autofs/root.c new file mode 100644 index 000000000000..a1ab1c0ed215 --- /dev/null +++ b/fs/autofs/root.c @@ -0,0 +1,564 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/root.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include <linux/errno.h> +#include <linux/stat.h> +#include <linux/param.h> +#include <linux/time.h> +#include <linux/smp_lock.h> +#include "autofs_i.h" + +static int autofs_root_readdir(struct file *,void *,filldir_t); +static struct dentry *autofs_root_lookup(struct inode *,struct dentry *, struct nameidata *); +static int autofs_root_symlink(struct inode *,struct dentry *,const char *); +static int autofs_root_unlink(struct inode *,struct dentry *); +static int autofs_root_rmdir(struct inode *,struct dentry *); +static int autofs_root_mkdir(struct inode *,struct dentry *,int); +static int autofs_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long); + +struct file_operations autofs_root_operations = { + .read = generic_read_dir, + .readdir = autofs_root_readdir, + .ioctl = autofs_root_ioctl, +}; + +struct inode_operations autofs_root_inode_operations = { + .lookup = autofs_root_lookup, + .unlink = autofs_root_unlink, + .symlink = autofs_root_symlink, + .mkdir = autofs_root_mkdir, + .rmdir = autofs_root_rmdir, +}; + +static int autofs_root_readdir(struct file *filp, void *dirent, filldir_t filldir) +{ + struct autofs_dir_ent *ent = NULL; + struct autofs_dirhash *dirhash; + struct autofs_sb_info *sbi; + struct inode * inode = filp->f_dentry->d_inode; + off_t onr, nr; + + lock_kernel(); + + sbi = autofs_sbi(inode->i_sb); + dirhash = &sbi->dirhash; + nr = filp->f_pos; + + switch(nr) + { + case 0: + if (filldir(dirent, ".", 1, nr, inode->i_ino, DT_DIR) < 0) + goto out; + filp->f_pos = ++nr; + /* fall through */ + case 1: + if (filldir(dirent, "..", 2, nr, inode->i_ino, DT_DIR) < 0) + goto out; + filp->f_pos = ++nr; + /* fall through */ + default: + while ( onr = nr, ent = autofs_hash_enum(dirhash,&nr,ent) ) { + if ( !ent->dentry || d_mountpoint(ent->dentry) ) { + if (filldir(dirent,ent->name,ent->len,onr,ent->ino,DT_UNKNOWN) < 0) + goto out; + filp->f_pos = nr; + } + } + break; + } + +out: + unlock_kernel(); + return 0; +} + +static int try_to_fill_dentry(struct dentry *dentry, struct super_block *sb, struct autofs_sb_info *sbi) +{ + struct inode * inode; + struct autofs_dir_ent *ent; + int status = 0; + + if ( !(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name)) ) { + do { + if ( status && dentry->d_inode ) { + if ( status != -ENOENT ) + printk("autofs warning: lookup failure on positive dentry, status = %d, name = %s\n", status, dentry->d_name.name); + 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; + dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; + return 1; + } else if (status) { + /* Return a negative dentry, but leave it "pending" */ + return 1; + } + status = autofs_wait(sbi, &dentry->d_name); + } while (!(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name)) ); + } + + /* Abuse this field as a pointer to the directory entry, used to + find the expire list pointers */ + dentry->d_time = (unsigned long) ent; + + if (!dentry->d_inode) { + inode = iget(sb, ent->ino); + if (!inode) { + /* Failed, but leave pending for next time */ + return 1; + } + dentry->d_inode = inode; + } + + /* If this is a directory that isn't a mount point, bitch at the + daemon and fix it in user space */ + if ( S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) ) { + return !autofs_wait(sbi, &dentry->d_name); + } + + /* We don't update the usages for the autofs daemon itself, this + is necessary for recursive autofs mounts */ + if ( !autofs_oz_mode(sbi) ) { + autofs_update_usage(&sbi->dirhash,ent); + } + + dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; + return 1; +} + + +/* + * Revalidate is called on every cache lookup. Some of those + * cache lookups may actually happen while the dentry is not + * yet completely filled in, and revalidate has to delay such + * lookups.. + */ +static int autofs_revalidate(struct dentry * dentry, struct nameidata *nd) +{ + struct inode * dir; + struct autofs_sb_info *sbi; + struct autofs_dir_ent *ent; + int res; + + lock_kernel(); + dir = dentry->d_parent->d_inode; + sbi = autofs_sbi(dir->i_sb); + + /* Pending dentry */ + if ( dentry->d_flags & DCACHE_AUTOFS_PENDING ) { + if (autofs_oz_mode(sbi)) + res = 1; + else + res = try_to_fill_dentry(dentry, dir->i_sb, sbi); + unlock_kernel(); + return res; + } + + /* Negative dentry.. invalidate if "old" */ + if (!dentry->d_inode) { + unlock_kernel(); + return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT); + } + + /* Check for a non-mountpoint directory */ + if ( S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) ) { + if (autofs_oz_mode(sbi)) + res = 1; + else + res = try_to_fill_dentry(dentry, dir->i_sb, sbi); + unlock_kernel(); + return res; + } + + /* Update the usage list */ + if ( !autofs_oz_mode(sbi) ) { + ent = (struct autofs_dir_ent *) dentry->d_time; + if ( ent ) + autofs_update_usage(&sbi->dirhash,ent); + } + unlock_kernel(); + return 1; +} + +static struct dentry_operations autofs_dentry_operations = { + .d_revalidate = autofs_revalidate, +}; + +static struct dentry *autofs_root_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) +{ + struct autofs_sb_info *sbi; + int oz_mode; + + DPRINTK(("autofs_root_lookup: name = ")); + lock_kernel(); + autofs_say(dentry->d_name.name,dentry->d_name.len); + + if (dentry->d_name.len > NAME_MAX) { + unlock_kernel(); + return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */ + } + + sbi = autofs_sbi(dir->i_sb); + + oz_mode = autofs_oz_mode(sbi); + DPRINTK(("autofs_lookup: pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d\n", + 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 = &autofs_dentry_operations; + dentry->d_flags |= DCACHE_AUTOFS_PENDING; + d_add(dentry, NULL); + + up(&dir->i_sem); + autofs_revalidate(dentry, nd); + down(&dir->i_sem); + + /* + * If we are still pending, check if we had to handle + * a signal. If so we can force a restart.. + */ + if (dentry->d_flags & DCACHE_AUTOFS_PENDING) { + /* See if we were interrupted */ + if (signal_pending(current)) { + sigset_t *sigset = ¤t->pending.signal; + if (sigismember (sigset, SIGKILL) || + sigismember (sigset, SIGQUIT) || + sigismember (sigset, SIGINT)) { + unlock_kernel(); + return ERR_PTR(-ERESTARTNOINTR); + } + } + } + unlock_kernel(); + + /* + * 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. + */ + if ( dentry->d_inode && d_unhashed(dentry) ) + return ERR_PTR(-ENOENT); + + return NULL; +} + +static int autofs_root_symlink(struct inode *dir, struct dentry *dentry, const char *symname) +{ + struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb); + struct autofs_dirhash *dh = &sbi->dirhash; + struct autofs_dir_ent *ent; + unsigned int n; + int slsize; + struct autofs_symlink *sl; + + DPRINTK(("autofs_root_symlink: %s <- ", symname)); + autofs_say(dentry->d_name.name,dentry->d_name.len); + + lock_kernel(); + if ( !autofs_oz_mode(sbi) ) { + unlock_kernel(); + return -EACCES; + } + + if ( autofs_hash_lookup(dh, &dentry->d_name) ) { + unlock_kernel(); + return -EEXIST; + } + + n = find_first_zero_bit(sbi->symlink_bitmap,AUTOFS_MAX_SYMLINKS); + if ( n >= AUTOFS_MAX_SYMLINKS ) { + unlock_kernel(); + return -ENOSPC; + } + + set_bit(n,sbi->symlink_bitmap); + sl = &sbi->symlink[n]; + sl->len = strlen(symname); + sl->data = kmalloc(slsize = sl->len+1, GFP_KERNEL); + if ( !sl->data ) { + clear_bit(n,sbi->symlink_bitmap); + unlock_kernel(); + return -ENOSPC; + } + + ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL); + if ( !ent ) { + kfree(sl->data); + clear_bit(n,sbi->symlink_bitmap); + unlock_kernel(); + return -ENOSPC; + } + + ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL); + if ( !ent->name ) { + kfree(sl->data); + kfree(ent); + clear_bit(n,sbi->symlink_bitmap); + unlock_kernel(); + return -ENOSPC; + } + + memcpy(sl->data,symname,slsize); + sl->mtime = get_seconds(); + + ent->ino = AUTOFS_FIRST_SYMLINK + n; + ent->hash = dentry->d_name.hash; + memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len)); + ent->dentry = NULL; /* We don't keep the dentry for symlinks */ + + autofs_hash_insert(dh,ent); + d_instantiate(dentry, iget(dir->i_sb,ent->ino)); + unlock_kernel(); + return 0; +} + +/* + * NOTE! + * + * 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, which we + * obviously do not want (we're dropping the entry not because it + * doesn't exist, but because it has timed out). + * + * Also see autofs_root_rmdir().. + */ +static int autofs_root_unlink(struct inode *dir, struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb); + struct autofs_dirhash *dh = &sbi->dirhash; + struct autofs_dir_ent *ent; + unsigned int n; + + /* This allows root to remove symlinks */ + lock_kernel(); + if ( !autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) ) { + unlock_kernel(); + return -EACCES; + } + + ent = autofs_hash_lookup(dh, &dentry->d_name); + if ( !ent ) { + unlock_kernel(); + return -ENOENT; + } + + n = ent->ino - AUTOFS_FIRST_SYMLINK; + if ( n >= AUTOFS_MAX_SYMLINKS ) { + unlock_kernel(); + return -EISDIR; /* It's a directory, dummy */ + } + if ( !test_bit(n,sbi->symlink_bitmap) ) { + unlock_kernel(); + return -EINVAL; /* Nonexistent symlink? Shouldn't happen */ + } + + dentry->d_time = (unsigned long)(struct autofs_dirhash *)NULL; + autofs_hash_delete(ent); + clear_bit(n,sbi->symlink_bitmap); + kfree(sbi->symlink[n].data); + d_drop(dentry); + + unlock_kernel(); + return 0; +} + +static int autofs_root_rmdir(struct inode *dir, struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb); + struct autofs_dirhash *dh = &sbi->dirhash; + struct autofs_dir_ent *ent; + + lock_kernel(); + if ( !autofs_oz_mode(sbi) ) { + unlock_kernel(); + return -EACCES; + } + + ent = autofs_hash_lookup(dh, &dentry->d_name); + if ( !ent ) { + unlock_kernel(); + return -ENOENT; + } + + if ( (unsigned int)ent->ino < AUTOFS_FIRST_DIR_INO ) { + unlock_kernel(); + return -ENOTDIR; /* Not a directory */ + } + + if ( ent->dentry != dentry ) { + printk("autofs_rmdir: odentry != dentry for entry %s\n", dentry->d_name.name); + } + + dentry->d_time = (unsigned long)(struct autofs_dir_ent *)NULL; + autofs_hash_delete(ent); + dir->i_nlink--; + d_drop(dentry); + unlock_kernel(); + + return 0; +} + +static int autofs_root_mkdir(struct inode *dir, struct dentry *dentry, int mode) +{ + struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb); + struct autofs_dirhash *dh = &sbi->dirhash; + struct autofs_dir_ent *ent; + ino_t ino; + + lock_kernel(); + if ( !autofs_oz_mode(sbi) ) { + unlock_kernel(); + return -EACCES; + } + + ent = autofs_hash_lookup(dh, &dentry->d_name); + if ( ent ) { + unlock_kernel(); + return -EEXIST; + } + + if ( sbi->next_dir_ino < AUTOFS_FIRST_DIR_INO ) { + printk("autofs: Out of inode numbers -- what the heck did you do??\n"); + unlock_kernel(); + return -ENOSPC; + } + ino = sbi->next_dir_ino++; + + ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL); + if ( !ent ) { + unlock_kernel(); + return -ENOSPC; + } + + ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL); + if ( !ent->name ) { + kfree(ent); + unlock_kernel(); + return -ENOSPC; + } + + ent->hash = dentry->d_name.hash; + memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len)); + ent->ino = ino; + ent->dentry = dentry; + autofs_hash_insert(dh,ent); + + dir->i_nlink++; + d_instantiate(dentry, iget(dir->i_sb,ino)); + unlock_kernel(); + + return 0; +} + +/* Get/set timeout ioctl() operation */ +static inline int autofs_get_set_timeout(struct autofs_sb_info *sbi, + unsigned long __user *p) +{ + unsigned long ntimeout; + + if (get_user(ntimeout, p) || + put_user(sbi->exp_timeout / HZ, p)) + return -EFAULT; + + if ( ntimeout > ULONG_MAX/HZ ) + sbi->exp_timeout = 0; + else + sbi->exp_timeout = ntimeout * HZ; + + return 0; +} + +/* Return protocol version */ +static inline int autofs_get_protover(int __user *p) +{ + return put_user(AUTOFS_PROTO_VERSION, p); +} + +/* Perform an expiry operation */ +static inline int autofs_expire_run(struct super_block *sb, + struct autofs_sb_info *sbi, + struct vfsmount *mnt, + struct autofs_packet_expire __user *pkt_p) +{ + struct autofs_dir_ent *ent; + struct autofs_packet_expire pkt; + + memset(&pkt,0,sizeof pkt); + + pkt.hdr.proto_version = AUTOFS_PROTO_VERSION; + pkt.hdr.type = autofs_ptype_expire; + + if ( !sbi->exp_timeout || + !(ent = autofs_expire(sb,sbi,mnt)) ) + return -EAGAIN; + + pkt.len = ent->len; + memcpy(pkt.name, ent->name, pkt.len); + pkt.name[pkt.len] = '\0'; + + if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) ) + return -EFAULT; + + return 0; +} + +/* + * ioctl()'s on the root directory is the chief method for the daemon to + * generate kernel reactions + */ +static int autofs_root_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb); + void __user *argp = (void __user *)arg; + + DPRINTK(("autofs_ioctl: cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u\n",cmd,arg,sbi,process_group(current))); + + if ( _IOC_TYPE(cmd) != _IOC_TYPE(AUTOFS_IOC_FIRST) || + _IOC_NR(cmd) - _IOC_NR(AUTOFS_IOC_FIRST) >= AUTOFS_IOC_COUNT ) + return -ENOTTY; + + if ( !autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) ) + return -EPERM; + + switch(cmd) { + case AUTOFS_IOC_READY: /* Wait queue: go ahead and retry */ + return autofs_wait_release(sbi,(autofs_wqt_t)arg,0); + case AUTOFS_IOC_FAIL: /* Wait queue: fail with ENOENT */ + return autofs_wait_release(sbi,(autofs_wqt_t)arg,-ENOENT); + case AUTOFS_IOC_CATATONIC: /* Enter catatonic mode (daemon shutdown) */ + autofs_catatonic_mode(sbi); + return 0; + case AUTOFS_IOC_PROTOVER: /* Get protocol version */ + return autofs_get_protover(argp); + case AUTOFS_IOC_SETTIMEOUT: + return autofs_get_set_timeout(sbi, argp); + case AUTOFS_IOC_EXPIRE: + return autofs_expire_run(inode->i_sb, sbi, filp->f_vfsmnt, + argp); + default: + return -ENOSYS; + } +} diff --git a/fs/autofs/symlink.c b/fs/autofs/symlink.c new file mode 100644 index 000000000000..f028396f1383 --- /dev/null +++ b/fs/autofs/symlink.c @@ -0,0 +1,25 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/symlink.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include "autofs_i.h" + +static int autofs_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + char *s=((struct autofs_symlink *)dentry->d_inode->u.generic_ip)->data; + nd_set_link(nd, s); + return 0; +} + +struct inode_operations autofs_symlink_inode_operations = { + .readlink = generic_readlink, + .follow_link = autofs_follow_link +}; diff --git a/fs/autofs/waitq.c b/fs/autofs/waitq.c new file mode 100644 index 000000000000..1fcaa1568541 --- /dev/null +++ b/fs/autofs/waitq.c @@ -0,0 +1,206 @@ +/* -*- linux-c -*- --------------------------------------------------------- * + * + * linux/fs/autofs/waitq.c + * + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * + * 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 + * option, any later version, incorporated herein by reference. + * + * ------------------------------------------------------------------------- */ + +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/signal.h> +#include <linux/file.h> +#include "autofs_i.h" + +/* We make this a static variable rather than a part of the superblock; it + is better if we don't reassign numbers easily even across filesystems */ +static autofs_wqt_t autofs_next_wait_queue = 1; + +/* These are the signals we allow interrupting a pending mount */ +#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | sigmask(SIGQUIT)) + +void autofs_catatonic_mode(struct autofs_sb_info *sbi) +{ + struct autofs_wait_queue *wq, *nwq; + + DPRINTK(("autofs: entering catatonic mode\n")); + + sbi->catatonic = 1; + wq = sbi->queues; + sbi->queues = NULL; /* Erase all wait queues */ + while ( wq ) { + nwq = wq->next; + wq->status = -ENOENT; /* Magic is gone - report failure */ + kfree(wq->name); + wq->name = NULL; + wake_up(&wq->queue); + wq = nwq; + } + fput(sbi->pipe); /* Close the pipe */ + autofs_hash_dputall(&sbi->dirhash); /* Remove all dentry pointers */ +} + +static int autofs_write(struct file *file, const void *addr, int bytes) +{ + unsigned long sigpipe, flags; + mm_segment_t fs; + const char *data = (const char *)addr; + ssize_t wr = 0; + + /** WARNING: this is not safe for writing more than PIPE_BUF bytes! **/ + + sigpipe = sigismember(¤t->pending.signal, SIGPIPE); + + /* Save pointer to user space and point back to kernel space */ + fs = get_fs(); + set_fs(KERNEL_DS); + + while (bytes && + (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) { + data += wr; + bytes -= wr; + } + + set_fs(fs); + + /* Keep the currently executing process from receiving a + SIGPIPE unless it was already supposed to get one */ + if (wr == -EPIPE && !sigpipe) { + spin_lock_irqsave(¤t->sighand->siglock, flags); + sigdelset(¤t->pending.signal, SIGPIPE); + recalc_sigpending(); + spin_unlock_irqrestore(¤t->sighand->siglock, flags); + } + + return (bytes > 0); +} + +static void autofs_notify_daemon(struct autofs_sb_info *sbi, struct autofs_wait_queue *wq) +{ + struct autofs_packet_missing pkt; + + DPRINTK(("autofs_wait: wait id = 0x%08lx, name = ", wq->wait_queue_token)); + autofs_say(wq->name,wq->len); + + memset(&pkt,0,sizeof pkt); /* For security reasons */ + + pkt.hdr.proto_version = AUTOFS_PROTO_VERSION; + pkt.hdr.type = autofs_ptype_missing; + pkt.wait_queue_token = wq->wait_queue_token; + pkt.len = wq->len; + memcpy(pkt.name, wq->name, pkt.len); + pkt.name[pkt.len] = '\0'; + + if ( autofs_write(sbi->pipe,&pkt,sizeof(struct autofs_packet_missing)) ) + autofs_catatonic_mode(sbi); +} + +int autofs_wait(struct autofs_sb_info *sbi, struct qstr *name) +{ + struct autofs_wait_queue *wq; + int status; + + /* In catatonic mode, we don't wait for nobody */ + if ( sbi->catatonic ) + return -ENOENT; + + /* We shouldn't be able to get here, but just in case */ + if ( name->len > NAME_MAX ) + return -ENOENT; + + for ( wq = sbi->queues ; wq ; wq = wq->next ) { + if ( wq->hash == name->hash && + wq->len == name->len && + wq->name && !memcmp(wq->name,name->name,name->len) ) + break; + } + + if ( !wq ) { + /* Create a new wait queue */ + wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL); + if ( !wq ) + return -ENOMEM; + + wq->name = kmalloc(name->len,GFP_KERNEL); + if ( !wq->name ) { + kfree(wq); + return -ENOMEM; + } + wq->wait_queue_token = autofs_next_wait_queue++; + init_waitqueue_head(&wq->queue); + wq->hash = name->hash; + wq->len = name->len; + wq->status = -EINTR; /* Status return if interrupted */ + memcpy(wq->name, name->name, name->len); + wq->next = sbi->queues; + sbi->queues = wq; + + /* autofs_notify_daemon() may block */ + wq->wait_ctr = 2; + autofs_notify_daemon(sbi,wq); + } else + wq->wait_ctr++; + + /* 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 ) { + /* Block all but "shutdown" signals while waiting */ + sigset_t sigmask; + + siginitsetinv(&sigmask, SHUTDOWN_SIGS); + sigprocmask(SIG_BLOCK, &sigmask, &sigmask); + + interruptible_sleep_on(&wq->queue); + + sigprocmask(SIG_SETMASK, &sigmask, NULL); + } else { + DPRINTK(("autofs_wait: skipped sleeping\n")); + } + + status = wq->status; + + if ( ! --wq->wait_ctr ) /* Are we the last process to need status? */ + kfree(wq); + + return status; +} + + +int autofs_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_token, int status) +{ + struct autofs_wait_queue *wq, **wql; + + for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) { + if ( wq->wait_queue_token == wait_queue_token ) + break; + } + if ( !wq ) + return -EINVAL; + + *wql = wq->next; /* Unlink from chain */ + kfree(wq->name); + wq->name = NULL; /* Do not wait on this queue */ + + wq->status = status; + + if ( ! --wq->wait_ctr ) /* Is anyone still waiting for this guy? */ + kfree(wq); + else + wake_up(&wq->queue); + + return 0; +} + |