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fs/super.c
29.2 KB
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/* * linux/fs/super.c * * Copyright (C) 1991, 1992 Linus Torvalds * * super.c contains code to handle: - mount structures * - super-block tables * - filesystem drivers list * - mount system call * - umount system call * - ustat system call * * GK 2/5/95 - Changed to support mounting the root fs via NFS * * Added kerneld support: Jacques Gelinas and Bjorn Ekwall * Added change_root: Werner Almesberger & Hans Lermen, Feb '96 * Added options to /proc/mounts: |
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* Torbjörn Lindh (torbjorn.lindh@gopta.se), April 14, 1996. |
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* Added devfs support: Richard Gooch <rgooch@atnf.csiro.au>, 13-JAN-1998 * Heavily rewritten for 'one fs - one tree' dcache architecture. AV, Mar 2000 */ |
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#include <linux/module.h> #include <linux/slab.h> |
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#include <linux/acct.h> #include <linux/blkdev.h> |
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#include <linux/mount.h> #include <linux/security.h> |
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#include <linux/writeback.h> /* for the emergency remount stuff */ #include <linux/idr.h> |
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#include <linux/mutex.h> |
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#include <linux/backing-dev.h> |
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#include <linux/rculist_bl.h> |
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#include <linux/cleancache.h> |
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#include "internal.h" |
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|
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LIST_HEAD(super_blocks); DEFINE_SPINLOCK(sb_lock); |
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/* * One thing we have to be careful of with a per-sb shrinker is that we don't * drop the last active reference to the superblock from within the shrinker. * If that happens we could trigger unregistering the shrinker from within the * shrinker path and that leads to deadlock on the shrinker_rwsem. Hence we * take a passive reference to the superblock to avoid this from occurring. */ static int prune_super(struct shrinker *shrink, struct shrink_control *sc) { struct super_block *sb; |
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int fs_objects = 0; int total_objects; |
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sb = container_of(shrink, struct super_block, s_shrink); /* * Deadlock avoidance. We may hold various FS locks, and we don't want * to recurse into the FS that called us in clear_inode() and friends.. */ if (sc->nr_to_scan && !(sc->gfp_mask & __GFP_FS)) return -1; if (!grab_super_passive(sb)) |
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return !sc->nr_to_scan ? 0 : -1; |
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|
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if (sb->s_op && sb->s_op->nr_cached_objects) fs_objects = sb->s_op->nr_cached_objects(sb); total_objects = sb->s_nr_dentry_unused + sb->s_nr_inodes_unused + fs_objects + 1; |
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if (sc->nr_to_scan) { |
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int dentries; int inodes; |
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|
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/* proportion the scan between the caches */ dentries = (sc->nr_to_scan * sb->s_nr_dentry_unused) / total_objects; inodes = (sc->nr_to_scan * sb->s_nr_inodes_unused) / total_objects; if (fs_objects) fs_objects = (sc->nr_to_scan * fs_objects) / total_objects; /* * prune the dcache first as the icache is pinned by it, then * prune the icache, followed by the filesystem specific caches */ prune_dcache_sb(sb, dentries); prune_icache_sb(sb, inodes); |
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|
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if (fs_objects && sb->s_op->free_cached_objects) { sb->s_op->free_cached_objects(sb, fs_objects); fs_objects = sb->s_op->nr_cached_objects(sb); } total_objects = sb->s_nr_dentry_unused + sb->s_nr_inodes_unused + fs_objects; |
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} |
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total_objects = (total_objects / 100) * sysctl_vfs_cache_pressure; |
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drop_super(sb); |
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return total_objects; |
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} |
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/** * alloc_super - create new superblock |
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* @type: filesystem type superblock should belong to |
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* * Allocates and initializes a new &struct super_block. alloc_super() * returns a pointer new superblock or %NULL if allocation had failed. */ |
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static struct super_block *alloc_super(struct file_system_type *type) |
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{ |
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struct super_block *s = kzalloc(sizeof(struct super_block), GFP_USER); |
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static const struct super_operations default_op; |
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if (s) { |
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if (security_sb_alloc(s)) { kfree(s); s = NULL; goto out; } |
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#ifdef CONFIG_SMP s->s_files = alloc_percpu(struct list_head); if (!s->s_files) { security_sb_free(s); kfree(s); s = NULL; goto out; } else { int i; for_each_possible_cpu(i) INIT_LIST_HEAD(per_cpu_ptr(s->s_files, i)); } #else |
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INIT_LIST_HEAD(&s->s_files); |
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#endif |
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s->s_bdi = &default_backing_dev_info; |
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INIT_HLIST_NODE(&s->s_instances); |
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INIT_HLIST_BL_HEAD(&s->s_anon); |
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INIT_LIST_HEAD(&s->s_inodes); |
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INIT_LIST_HEAD(&s->s_dentry_lru); |
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INIT_LIST_HEAD(&s->s_inode_lru); |
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spin_lock_init(&s->s_inode_lru_lock); |
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INIT_LIST_HEAD(&s->s_mounts); |
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init_rwsem(&s->s_umount); |
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mutex_init(&s->s_lock); |
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lockdep_set_class(&s->s_umount, &type->s_umount_key); |
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/* * The locking rules for s_lock are up to the * filesystem. For example ext3fs has different * lock ordering than usbfs: */ lockdep_set_class(&s->s_lock, &type->s_lock_key); |
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/* * sget() can have s_umount recursion. * * When it cannot find a suitable sb, it allocates a new * one (this one), and tries again to find a suitable old * one. * * In case that succeeds, it will acquire the s_umount * lock of the old one. Since these are clearly distrinct * locks, and this object isn't exposed yet, there's no * risk of deadlocks. * * Annotate this by putting this lock in a different * subclass. */ down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING); |
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s->s_count = 1; |
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atomic_set(&s->s_active, 1); |
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mutex_init(&s->s_vfs_rename_mutex); |
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lockdep_set_class(&s->s_vfs_rename_mutex, &type->s_vfs_rename_key); |
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mutex_init(&s->s_dquot.dqio_mutex); mutex_init(&s->s_dquot.dqonoff_mutex); |
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init_rwsem(&s->s_dquot.dqptr_sem); init_waitqueue_head(&s->s_wait_unfrozen); s->s_maxbytes = MAX_NON_LFS; |
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s->s_op = &default_op; s->s_time_gran = 1000000000; |
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s->cleancache_poolid = -1; |
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s->s_shrink.seeks = DEFAULT_SEEKS; s->s_shrink.shrink = prune_super; |
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s->s_shrink.batch = 1024; |
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} out: return s; } /** * destroy_super - frees a superblock * @s: superblock to free * * Frees a superblock. */ static inline void destroy_super(struct super_block *s) { |
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#ifdef CONFIG_SMP free_percpu(s->s_files); #endif |
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security_sb_free(s); |
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WARN_ON(!list_empty(&s->s_mounts)); |
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kfree(s->s_subtype); |
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kfree(s->s_options); |
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kfree(s); } /* Superblock refcounting */ /* |
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* Drop a superblock's refcount. The caller must hold sb_lock. |
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*/ |
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static void __put_super(struct super_block *sb) |
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{ |
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if (!--sb->s_count) { |
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list_del_init(&sb->s_list); |
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destroy_super(sb); |
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} |
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} /** * put_super - drop a temporary reference to superblock * @sb: superblock in question * * Drops a temporary reference, frees superblock if there's no * references left. */ |
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static void put_super(struct super_block *sb) |
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{ spin_lock(&sb_lock); __put_super(sb); spin_unlock(&sb_lock); } /** |
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* deactivate_locked_super - drop an active reference to superblock |
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* @s: superblock to deactivate * |
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* Drops an active reference to superblock, converting it into a temprory * one if there is no other active references left. In that case we |
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* tell fs driver to shut it down and drop the temporary reference we * had just acquired. |
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* * Caller holds exclusive lock on superblock; that lock is released. |
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*/ |
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void deactivate_locked_super(struct super_block *s) |
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{ struct file_system_type *fs = s->s_type; |
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if (atomic_dec_and_test(&s->s_active)) { |
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cleancache_flush_fs(s); |
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fs->kill_sb(s); |
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/* caches are now gone, we can safely kill the shrinker now */ unregister_shrinker(&s->s_shrink); |
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/* * We need to call rcu_barrier so all the delayed rcu free * inodes are flushed before we release the fs module. */ rcu_barrier(); |
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put_filesystem(fs); put_super(s); |
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} else { up_write(&s->s_umount); |
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} } |
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EXPORT_SYMBOL(deactivate_locked_super); |
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/** |
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* deactivate_super - drop an active reference to superblock |
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* @s: superblock to deactivate * |
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* Variant of deactivate_locked_super(), except that superblock is *not* * locked by caller. If we are going to drop the final active reference, * lock will be acquired prior to that. |
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*/ |
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void deactivate_super(struct super_block *s) |
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{ |
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if (!atomic_add_unless(&s->s_active, -1, 1)) { down_write(&s->s_umount); deactivate_locked_super(s); |
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} } |
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EXPORT_SYMBOL(deactivate_super); |
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/** |
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* grab_super - acquire an active reference * @s: reference we are trying to make active * * Tries to acquire an active reference. grab_super() is used when we * had just found a superblock in super_blocks or fs_type->fs_supers * and want to turn it into a full-blown active reference. grab_super() * is called with sb_lock held and drops it. Returns 1 in case of * success, 0 if we had failed (superblock contents was already dead or * dying when grab_super() had been called). */ |
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static int grab_super(struct super_block *s) __releases(sb_lock) |
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{ |
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if (atomic_inc_not_zero(&s->s_active)) { spin_unlock(&sb_lock); |
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return 1; } /* it's going away */ |
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s->s_count++; spin_unlock(&sb_lock); |
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/* wait for it to die */ |
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down_write(&s->s_umount); |
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up_write(&s->s_umount); put_super(s); |
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return 0; } |
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/* |
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* grab_super_passive - acquire a passive reference * @s: reference we are trying to grab * * Tries to acquire a passive reference. This is used in places where we * cannot take an active reference but we need to ensure that the * superblock does not go away while we are working on it. It returns * false if a reference was not gained, and returns true with the s_umount * lock held in read mode if a reference is gained. On successful return, * the caller must drop the s_umount lock and the passive reference when * done. */ bool grab_super_passive(struct super_block *sb) { spin_lock(&sb_lock); |
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if (hlist_unhashed(&sb->s_instances)) { |
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spin_unlock(&sb_lock); return false; } sb->s_count++; spin_unlock(&sb_lock); if (down_read_trylock(&sb->s_umount)) { |
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if (sb->s_root && (sb->s_flags & MS_BORN)) |
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return true; up_read(&sb->s_umount); } put_super(sb); return false; } /* |
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* Superblock locking. We really ought to get rid of these two. */ void lock_super(struct super_block * sb) { |
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mutex_lock(&sb->s_lock); } void unlock_super(struct super_block * sb) { |
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mutex_unlock(&sb->s_lock); } EXPORT_SYMBOL(lock_super); EXPORT_SYMBOL(unlock_super); |
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/** * generic_shutdown_super - common helper for ->kill_sb() * @sb: superblock to kill * * generic_shutdown_super() does all fs-independent work on superblock * shutdown. Typical ->kill_sb() should pick all fs-specific objects * that need destruction out of superblock, call generic_shutdown_super() * and release aforementioned objects. Note: dentries and inodes _are_ * taken care of and do not need specific handling. |
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* * Upon calling this function, the filesystem may no longer alter or * rearrange the set of dentries belonging to this super_block, nor may it * change the attachments of dentries to inodes. |
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*/ void generic_shutdown_super(struct super_block *sb) { |
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const struct super_operations *sop = sb->s_op; |
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|
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if (sb->s_root) { shrink_dcache_for_umount(sb); |
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sync_filesystem(sb); |
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sb->s_flags &= ~MS_ACTIVE; |
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|
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fsnotify_unmount_inodes(&sb->s_inodes); evict_inodes(sb); |
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|
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if (sop->put_super) sop->put_super(sb); |
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if (!list_empty(&sb->s_inodes)) { |
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printk("VFS: Busy inodes after unmount of %s. " "Self-destruct in 5 seconds. Have a nice day... ", sb->s_id); |
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} |
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} spin_lock(&sb_lock); /* should be initialized for __put_super_and_need_restart() */ |
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hlist_del_init(&sb->s_instances); |
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spin_unlock(&sb_lock); up_write(&sb->s_umount); } EXPORT_SYMBOL(generic_shutdown_super); /** * sget - find or create a superblock * @type: filesystem type superblock should belong to * @test: comparison callback * @set: setup callback * @data: argument to each of them */ struct super_block *sget(struct file_system_type *type, int (*test)(struct super_block *,void *), int (*set)(struct super_block *,void *), void *data) { struct super_block *s = NULL; |
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struct hlist_node *node; |
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struct super_block *old; |
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int err; retry: spin_lock(&sb_lock); |
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if (test) { |
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hlist_for_each_entry(old, node, &type->fs_supers, s_instances) { |
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if (!test(old, data)) continue; if (!grab_super(old)) goto retry; |
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if (s) { up_write(&s->s_umount); |
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destroy_super(s); |
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s = NULL; |
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} |
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down_write(&old->s_umount); |
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if (unlikely(!(old->s_flags & MS_BORN))) { deactivate_locked_super(old); goto retry; } |
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return old; } |
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} if (!s) { spin_unlock(&sb_lock); |
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s = alloc_super(type); |
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if (!s) return ERR_PTR(-ENOMEM); goto retry; } err = set(s, data); if (err) { spin_unlock(&sb_lock); |
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up_write(&s->s_umount); |
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destroy_super(s); return ERR_PTR(err); } s->s_type = type; strlcpy(s->s_id, type->name, sizeof(s->s_id)); list_add_tail(&s->s_list, &super_blocks); |
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hlist_add_head(&s->s_instances, &type->fs_supers); |
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spin_unlock(&sb_lock); get_filesystem(type); |
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register_shrinker(&s->s_shrink); |
1da177e4c Linux-2.6.12-rc2 |
461 462 463 464 465 466 467 468 469 470 471 472 |
return s; } EXPORT_SYMBOL(sget); void drop_super(struct super_block *sb) { up_read(&sb->s_umount); put_super(sb); } EXPORT_SYMBOL(drop_super); |
e50047533 cleanup sync_supers |
473 474 475 476 477 478 479 480 |
/** * sync_supers - helper for periodic superblock writeback * * Call the write_super method if present on all dirty superblocks in * the system. This is for the periodic writeback used by most older * filesystems. For data integrity superblock writeback use * sync_filesystems() instead. * |
1da177e4c Linux-2.6.12-rc2 |
481 482 483 484 485 486 |
* Note: check the dirty flag before waiting, so we don't * hold up the sync while mounting a device. (The newly * mounted device won't need syncing.) */ void sync_supers(void) { |
dca332528 no need for list_... |
487 |
struct super_block *sb, *p = NULL; |
618f06362 [PATCH] O(1) sb l... |
488 |
|
1da177e4c Linux-2.6.12-rc2 |
489 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
490 |
list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
491 |
if (hlist_unhashed(&sb->s_instances)) |
551de6f34 Leave superblocks... |
492 |
continue; |
e50047533 cleanup sync_supers |
493 |
if (sb->s_op->write_super && sb->s_dirt) { |
1da177e4c Linux-2.6.12-rc2 |
494 495 |
sb->s_count++; spin_unlock(&sb_lock); |
e50047533 cleanup sync_supers |
496 |
|
1da177e4c Linux-2.6.12-rc2 |
497 |
down_read(&sb->s_umount); |
dabe0dc19 vfs: fix the rest... |
498 |
if (sb->s_root && sb->s_dirt && (sb->s_flags & MS_BORN)) |
e50047533 cleanup sync_supers |
499 |
sb->s_op->write_super(sb); |
618f06362 [PATCH] O(1) sb l... |
500 |
up_read(&sb->s_umount); |
e50047533 cleanup sync_supers |
501 |
|
618f06362 [PATCH] O(1) sb l... |
502 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
503 504 505 |
if (p) __put_super(p); p = sb; |
618f06362 [PATCH] O(1) sb l... |
506 507 |
} } |
dca332528 no need for list_... |
508 509 |
if (p) __put_super(p); |
1da177e4c Linux-2.6.12-rc2 |
510 511 |
spin_unlock(&sb_lock); } |
1da177e4c Linux-2.6.12-rc2 |
512 |
/** |
01a05b337 new helper: itera... |
513 514 515 516 517 518 519 520 521 |
* iterate_supers - call function for all active superblocks * @f: function to call * @arg: argument to pass to it * * Scans the superblock list and calls given function, passing it * locked superblock and given argument. */ void iterate_supers(void (*f)(struct super_block *, void *), void *arg) { |
dca332528 no need for list_... |
522 |
struct super_block *sb, *p = NULL; |
01a05b337 new helper: itera... |
523 524 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
525 |
list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
526 |
if (hlist_unhashed(&sb->s_instances)) |
01a05b337 new helper: itera... |
527 528 529 530 531 |
continue; sb->s_count++; spin_unlock(&sb_lock); down_read(&sb->s_umount); |
dabe0dc19 vfs: fix the rest... |
532 |
if (sb->s_root && (sb->s_flags & MS_BORN)) |
01a05b337 new helper: itera... |
533 534 535 536 |
f(sb, arg); up_read(&sb->s_umount); spin_lock(&sb_lock); |
dca332528 no need for list_... |
537 538 539 |
if (p) __put_super(p); p = sb; |
01a05b337 new helper: itera... |
540 |
} |
dca332528 no need for list_... |
541 542 |
if (p) __put_super(p); |
01a05b337 new helper: itera... |
543 544 545 546 |
spin_unlock(&sb_lock); } /** |
43e15cdbe new helper: itera... |
547 548 549 550 551 552 553 554 555 556 557 558 |
* iterate_supers_type - call function for superblocks of given type * @type: fs type * @f: function to call * @arg: argument to pass to it * * Scans the superblock list and calls given function, passing it * locked superblock and given argument. */ void iterate_supers_type(struct file_system_type *type, void (*f)(struct super_block *, void *), void *arg) { struct super_block *sb, *p = NULL; |
a5166169f vfs: convert fs_s... |
559 |
struct hlist_node *node; |
43e15cdbe new helper: itera... |
560 561 |
spin_lock(&sb_lock); |
a5166169f vfs: convert fs_s... |
562 |
hlist_for_each_entry(sb, node, &type->fs_supers, s_instances) { |
43e15cdbe new helper: itera... |
563 564 565 566 |
sb->s_count++; spin_unlock(&sb_lock); down_read(&sb->s_umount); |
dabe0dc19 vfs: fix the rest... |
567 |
if (sb->s_root && (sb->s_flags & MS_BORN)) |
43e15cdbe new helper: itera... |
568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 |
f(sb, arg); up_read(&sb->s_umount); spin_lock(&sb_lock); if (p) __put_super(p); p = sb; } if (p) __put_super(p); spin_unlock(&sb_lock); } EXPORT_SYMBOL(iterate_supers_type); /** |
1da177e4c Linux-2.6.12-rc2 |
584 585 586 587 588 589 |
* get_super - get the superblock of a device * @bdev: device to get the superblock for * * Scans the superblock list and finds the superblock of the file system * mounted on the device given. %NULL is returned if no match is found. */ |
df40c01a9 In get_super() an... |
590 |
struct super_block *get_super(struct block_device *bdev) |
1da177e4c Linux-2.6.12-rc2 |
591 |
{ |
618f06362 [PATCH] O(1) sb l... |
592 |
struct super_block *sb; |
1da177e4c Linux-2.6.12-rc2 |
593 594 |
if (!bdev) return NULL; |
618f06362 [PATCH] O(1) sb l... |
595 |
|
1da177e4c Linux-2.6.12-rc2 |
596 |
spin_lock(&sb_lock); |
618f06362 [PATCH] O(1) sb l... |
597 598 |
rescan: list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
599 |
if (hlist_unhashed(&sb->s_instances)) |
551de6f34 Leave superblocks... |
600 |
continue; |
618f06362 [PATCH] O(1) sb l... |
601 602 |
if (sb->s_bdev == bdev) { sb->s_count++; |
1da177e4c Linux-2.6.12-rc2 |
603 |
spin_unlock(&sb_lock); |
618f06362 [PATCH] O(1) sb l... |
604 |
down_read(&sb->s_umount); |
df40c01a9 In get_super() an... |
605 |
/* still alive? */ |
dabe0dc19 vfs: fix the rest... |
606 |
if (sb->s_root && (sb->s_flags & MS_BORN)) |
618f06362 [PATCH] O(1) sb l... |
607 608 |
return sb; up_read(&sb->s_umount); |
df40c01a9 In get_super() an... |
609 |
/* nope, got unmounted */ |
618f06362 [PATCH] O(1) sb l... |
610 |
spin_lock(&sb_lock); |
df40c01a9 In get_super() an... |
611 612 |
__put_super(sb); goto rescan; |
1da177e4c Linux-2.6.12-rc2 |
613 614 615 616 617 618 619 |
} } spin_unlock(&sb_lock); return NULL; } EXPORT_SYMBOL(get_super); |
4504230a7 freeze_bdev: grab... |
620 621 622 623 624 625 626 |
/** * get_active_super - get an active reference to the superblock of a device * @bdev: device to get the superblock for * * Scans the superblock list and finds the superblock of the file system * mounted on the device given. Returns the superblock with an active |
d3f214730 Move grabbing s_u... |
627 |
* reference or %NULL if none was found. |
4504230a7 freeze_bdev: grab... |
628 629 630 631 632 633 634 |
*/ struct super_block *get_active_super(struct block_device *bdev) { struct super_block *sb; if (!bdev) return NULL; |
1494583de fix get_active_su... |
635 |
restart: |
4504230a7 freeze_bdev: grab... |
636 637 |
spin_lock(&sb_lock); list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
638 |
if (hlist_unhashed(&sb->s_instances)) |
551de6f34 Leave superblocks... |
639 |
continue; |
1494583de fix get_active_su... |
640 641 642 643 644 645 |
if (sb->s_bdev == bdev) { if (grab_super(sb)) /* drops sb_lock */ return sb; else goto restart; } |
4504230a7 freeze_bdev: grab... |
646 647 648 649 |
} spin_unlock(&sb_lock); return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
650 |
|
df40c01a9 In get_super() an... |
651 |
struct super_block *user_get_super(dev_t dev) |
1da177e4c Linux-2.6.12-rc2 |
652 |
{ |
618f06362 [PATCH] O(1) sb l... |
653 |
struct super_block *sb; |
1da177e4c Linux-2.6.12-rc2 |
654 |
|
1da177e4c Linux-2.6.12-rc2 |
655 |
spin_lock(&sb_lock); |
618f06362 [PATCH] O(1) sb l... |
656 657 |
rescan: list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
658 |
if (hlist_unhashed(&sb->s_instances)) |
551de6f34 Leave superblocks... |
659 |
continue; |
618f06362 [PATCH] O(1) sb l... |
660 661 |
if (sb->s_dev == dev) { sb->s_count++; |
1da177e4c Linux-2.6.12-rc2 |
662 |
spin_unlock(&sb_lock); |
618f06362 [PATCH] O(1) sb l... |
663 |
down_read(&sb->s_umount); |
df40c01a9 In get_super() an... |
664 |
/* still alive? */ |
dabe0dc19 vfs: fix the rest... |
665 |
if (sb->s_root && (sb->s_flags & MS_BORN)) |
618f06362 [PATCH] O(1) sb l... |
666 667 |
return sb; up_read(&sb->s_umount); |
df40c01a9 In get_super() an... |
668 |
/* nope, got unmounted */ |
618f06362 [PATCH] O(1) sb l... |
669 |
spin_lock(&sb_lock); |
df40c01a9 In get_super() an... |
670 671 |
__put_super(sb); goto rescan; |
1da177e4c Linux-2.6.12-rc2 |
672 673 674 675 676 |
} } spin_unlock(&sb_lock); return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
677 |
/** |
1da177e4c Linux-2.6.12-rc2 |
678 679 680 681 682 683 684 685 686 687 688 |
* do_remount_sb - asks filesystem to change mount options. * @sb: superblock in question * @flags: numeric part of options * @data: the rest of options * @force: whether or not to force the change * * Alters the mount options of a mounted file system. */ int do_remount_sb(struct super_block *sb, int flags, void *data, int force) { int retval; |
c79d967de quota: move remou... |
689 |
int remount_ro; |
4504230a7 freeze_bdev: grab... |
690 691 692 |
if (sb->s_frozen != SB_UNFROZEN) return -EBUSY; |
9361401eb [PATCH] BLOCK: Ma... |
693 |
#ifdef CONFIG_BLOCK |
1da177e4c Linux-2.6.12-rc2 |
694 695 |
if (!(flags & MS_RDONLY) && bdev_read_only(sb->s_bdev)) return -EACCES; |
9361401eb [PATCH] BLOCK: Ma... |
696 |
#endif |
4504230a7 freeze_bdev: grab... |
697 |
|
1da177e4c Linux-2.6.12-rc2 |
698 699 700 |
if (flags & MS_RDONLY) acct_auto_close(sb); shrink_dcache_sb(sb); |
60b0680fa vfs: Rename fsync... |
701 |
sync_filesystem(sb); |
1da177e4c Linux-2.6.12-rc2 |
702 |
|
d208bbdda fs: improve remou... |
703 |
remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY); |
d208bbdda fs: improve remou... |
704 |
|
1da177e4c Linux-2.6.12-rc2 |
705 706 |
/* If we are remounting RDONLY and current sb is read/write, make sure there are no rw files opened */ |
d208bbdda fs: improve remou... |
707 |
if (remount_ro) { |
4ed5e82fe vfs: protect remo... |
708 |
if (force) { |
1da177e4c Linux-2.6.12-rc2 |
709 |
mark_files_ro(sb); |
4ed5e82fe vfs: protect remo... |
710 711 712 713 |
} else { retval = sb_prepare_remount_readonly(sb); if (retval) return retval; |
4ed5e82fe vfs: protect remo... |
714 |
} |
1da177e4c Linux-2.6.12-rc2 |
715 716 717 |
} if (sb->s_op->remount_fs) { |
1da177e4c Linux-2.6.12-rc2 |
718 |
retval = sb->s_op->remount_fs(sb, &flags, data); |
2833eb2b4 vfs: ignore error... |
719 720 |
if (retval) { if (!force) |
4ed5e82fe vfs: protect remo... |
721 |
goto cancel_readonly; |
2833eb2b4 vfs: ignore error... |
722 723 724 725 726 |
/* If forced remount, go ahead despite any errors */ WARN(1, "forced remount of a %s fs returned %i ", sb->s_type->name, retval); } |
1da177e4c Linux-2.6.12-rc2 |
727 728 |
} sb->s_flags = (sb->s_flags & ~MS_RMT_MASK) | (flags & MS_RMT_MASK); |
4ed5e82fe vfs: protect remo... |
729 730 731 |
/* Needs to be ordered wrt mnt_is_readonly() */ smp_wmb(); sb->s_readonly_remount = 0; |
c79d967de quota: move remou... |
732 |
|
d208bbdda fs: improve remou... |
733 734 735 736 737 738 739 740 741 742 |
/* * Some filesystems modify their metadata via some other path than the * bdev buffer cache (eg. use a private mapping, or directories in * pagecache, etc). Also file data modifications go via their own * mappings. So If we try to mount readonly then copy the filesystem * from bdev, we could get stale data, so invalidate it to give a best * effort at coherency. */ if (remount_ro && sb->s_bdev) invalidate_bdev(sb->s_bdev); |
1da177e4c Linux-2.6.12-rc2 |
743 |
return 0; |
4ed5e82fe vfs: protect remo... |
744 745 746 747 |
cancel_readonly: sb->s_readonly_remount = 0; return retval; |
1da177e4c Linux-2.6.12-rc2 |
748 |
} |
a2a9537ac Get rid of pdflus... |
749 |
static void do_emergency_remount(struct work_struct *work) |
1da177e4c Linux-2.6.12-rc2 |
750 |
{ |
dca332528 no need for list_... |
751 |
struct super_block *sb, *p = NULL; |
1da177e4c Linux-2.6.12-rc2 |
752 753 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
754 |
list_for_each_entry(sb, &super_blocks, s_list) { |
a5166169f vfs: convert fs_s... |
755 |
if (hlist_unhashed(&sb->s_instances)) |
551de6f34 Leave superblocks... |
756 |
continue; |
1da177e4c Linux-2.6.12-rc2 |
757 758 |
sb->s_count++; spin_unlock(&sb_lock); |
443b94baa Make sure that al... |
759 |
down_write(&sb->s_umount); |
dabe0dc19 vfs: fix the rest... |
760 761 |
if (sb->s_root && sb->s_bdev && (sb->s_flags & MS_BORN) && !(sb->s_flags & MS_RDONLY)) { |
1da177e4c Linux-2.6.12-rc2 |
762 |
/* |
1da177e4c Linux-2.6.12-rc2 |
763 764 |
* What lock protects sb->s_flags?? */ |
1da177e4c Linux-2.6.12-rc2 |
765 |
do_remount_sb(sb, MS_RDONLY, NULL, 1); |
1da177e4c Linux-2.6.12-rc2 |
766 |
} |
443b94baa Make sure that al... |
767 |
up_write(&sb->s_umount); |
1da177e4c Linux-2.6.12-rc2 |
768 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
769 770 771 |
if (p) __put_super(p); p = sb; |
1da177e4c Linux-2.6.12-rc2 |
772 |
} |
dca332528 no need for list_... |
773 774 |
if (p) __put_super(p); |
1da177e4c Linux-2.6.12-rc2 |
775 |
spin_unlock(&sb_lock); |
a2a9537ac Get rid of pdflus... |
776 |
kfree(work); |
1da177e4c Linux-2.6.12-rc2 |
777 778 779 780 781 782 |
printk("Emergency Remount complete "); } void emergency_remount(void) { |
a2a9537ac Get rid of pdflus... |
783 784 785 786 787 788 789 |
struct work_struct *work; work = kmalloc(sizeof(*work), GFP_ATOMIC); if (work) { INIT_WORK(work, do_emergency_remount); schedule_work(work); } |
1da177e4c Linux-2.6.12-rc2 |
790 791 792 793 794 795 |
} /* * Unnamed block devices are dummy devices used by virtual * filesystems which don't use real block-devices. -- jrs */ |
ad76cbc63 [PATCH 2/2] anond... |
796 |
static DEFINE_IDA(unnamed_dev_ida); |
1da177e4c Linux-2.6.12-rc2 |
797 |
static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */ |
c63e09ecc Make allocation o... |
798 |
static int unnamed_dev_start = 0; /* don't bother trying below it */ |
1da177e4c Linux-2.6.12-rc2 |
799 |
|
0ee5dc676 btrfs: kill magic... |
800 |
int get_anon_bdev(dev_t *p) |
1da177e4c Linux-2.6.12-rc2 |
801 802 803 804 805 |
{ int dev; int error; retry: |
ad76cbc63 [PATCH 2/2] anond... |
806 |
if (ida_pre_get(&unnamed_dev_ida, GFP_ATOMIC) == 0) |
1da177e4c Linux-2.6.12-rc2 |
807 808 |
return -ENOMEM; spin_lock(&unnamed_dev_lock); |
c63e09ecc Make allocation o... |
809 |
error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev); |
f21f62208 ... and the same ... |
810 811 |
if (!error) unnamed_dev_start = dev + 1; |
1da177e4c Linux-2.6.12-rc2 |
812 813 814 815 816 817 818 819 820 |
spin_unlock(&unnamed_dev_lock); if (error == -EAGAIN) /* We raced and lost with another CPU. */ goto retry; else if (error) return -EAGAIN; if ((dev & MAX_ID_MASK) == (1 << MINORBITS)) { spin_lock(&unnamed_dev_lock); |
ad76cbc63 [PATCH 2/2] anond... |
821 |
ida_remove(&unnamed_dev_ida, dev); |
f21f62208 ... and the same ... |
822 823 |
if (unnamed_dev_start > dev) unnamed_dev_start = dev; |
1da177e4c Linux-2.6.12-rc2 |
824 825 826 |
spin_unlock(&unnamed_dev_lock); return -EMFILE; } |
0ee5dc676 btrfs: kill magic... |
827 |
*p = MKDEV(0, dev & MINORMASK); |
1da177e4c Linux-2.6.12-rc2 |
828 829 |
return 0; } |
0ee5dc676 btrfs: kill magic... |
830 |
EXPORT_SYMBOL(get_anon_bdev); |
1da177e4c Linux-2.6.12-rc2 |
831 |
|
0ee5dc676 btrfs: kill magic... |
832 |
void free_anon_bdev(dev_t dev) |
1da177e4c Linux-2.6.12-rc2 |
833 |
{ |
0ee5dc676 btrfs: kill magic... |
834 |
int slot = MINOR(dev); |
1da177e4c Linux-2.6.12-rc2 |
835 |
spin_lock(&unnamed_dev_lock); |
ad76cbc63 [PATCH 2/2] anond... |
836 |
ida_remove(&unnamed_dev_ida, slot); |
c63e09ecc Make allocation o... |
837 838 |
if (slot < unnamed_dev_start) unnamed_dev_start = slot; |
1da177e4c Linux-2.6.12-rc2 |
839 840 |
spin_unlock(&unnamed_dev_lock); } |
0ee5dc676 btrfs: kill magic... |
841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 |
EXPORT_SYMBOL(free_anon_bdev); int set_anon_super(struct super_block *s, void *data) { int error = get_anon_bdev(&s->s_dev); if (!error) s->s_bdi = &noop_backing_dev_info; return error; } EXPORT_SYMBOL(set_anon_super); void kill_anon_super(struct super_block *sb) { dev_t dev = sb->s_dev; generic_shutdown_super(sb); free_anon_bdev(dev); } |
1da177e4c Linux-2.6.12-rc2 |
859 860 |
EXPORT_SYMBOL(kill_anon_super); |
1da177e4c Linux-2.6.12-rc2 |
861 862 863 864 865 866 867 868 |
void kill_litter_super(struct super_block *sb) { if (sb->s_root) d_genocide(sb->s_root); kill_anon_super(sb); } EXPORT_SYMBOL(kill_litter_super); |
909e6d947 namespaces: move ... |
869 870 871 872 873 874 875 876 877 878 |
static int ns_test_super(struct super_block *sb, void *data) { return sb->s_fs_info == data; } static int ns_set_super(struct super_block *sb, void *data) { sb->s_fs_info = data; return set_anon_super(sb, NULL); } |
ceefda693 switch get_sb_ns(... |
879 880 |
struct dentry *mount_ns(struct file_system_type *fs_type, int flags, void *data, int (*fill_super)(struct super_block *, void *, int)) |
909e6d947 namespaces: move ... |
881 882 883 884 885 |
{ struct super_block *sb; sb = sget(fs_type, ns_test_super, ns_set_super, data); if (IS_ERR(sb)) |
ceefda693 switch get_sb_ns(... |
886 |
return ERR_CAST(sb); |
909e6d947 namespaces: move ... |
887 888 889 890 891 892 |
if (!sb->s_root) { int err; sb->s_flags = flags; err = fill_super(sb, data, flags & MS_SILENT ? 1 : 0); if (err) { |
74dbbdd7f New helper: deact... |
893 |
deactivate_locked_super(sb); |
ceefda693 switch get_sb_ns(... |
894 |
return ERR_PTR(err); |
909e6d947 namespaces: move ... |
895 896 897 898 |
} sb->s_flags |= MS_ACTIVE; } |
ceefda693 switch get_sb_ns(... |
899 |
return dget(sb->s_root); |
909e6d947 namespaces: move ... |
900 |
} |
ceefda693 switch get_sb_ns(... |
901 |
EXPORT_SYMBOL(mount_ns); |
909e6d947 namespaces: move ... |
902 |
|
9361401eb [PATCH] BLOCK: Ma... |
903 |
#ifdef CONFIG_BLOCK |
1da177e4c Linux-2.6.12-rc2 |
904 905 906 907 |
static int set_bdev_super(struct super_block *s, void *data) { s->s_bdev = data; s->s_dev = s->s_bdev->bd_dev; |
32a88aa1b fs: Assign bdi in... |
908 909 910 911 912 913 |
/* * We set the bdi here to the queue backing, file systems can * overwrite this in ->fill_super() */ s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info; |
1da177e4c Linux-2.6.12-rc2 |
914 915 916 917 918 919 920 |
return 0; } static int test_bdev_super(struct super_block *s, void *data) { return (void *)s->s_bdev == data; } |
152a08366 new helper: mount... |
921 |
struct dentry *mount_bdev(struct file_system_type *fs_type, |
1da177e4c Linux-2.6.12-rc2 |
922 |
int flags, const char *dev_name, void *data, |
152a08366 new helper: mount... |
923 |
int (*fill_super)(struct super_block *, void *, int)) |
1da177e4c Linux-2.6.12-rc2 |
924 925 926 |
{ struct block_device *bdev; struct super_block *s; |
d4d776299 block: clean up b... |
927 |
fmode_t mode = FMODE_READ | FMODE_EXCL; |
1da177e4c Linux-2.6.12-rc2 |
928 |
int error = 0; |
30c40d2c0 [PATCH] propagate... |
929 930 |
if (!(flags & MS_RDONLY)) mode |= FMODE_WRITE; |
d4d776299 block: clean up b... |
931 |
bdev = blkdev_get_by_path(dev_name, mode, fs_type); |
1da177e4c Linux-2.6.12-rc2 |
932 |
if (IS_ERR(bdev)) |
152a08366 new helper: mount... |
933 |
return ERR_CAST(bdev); |
1da177e4c Linux-2.6.12-rc2 |
934 935 936 937 938 939 |
/* * once the super is inserted into the list by sget, s_umount * will protect the lockfs code from trying to start a snapshot * while we are mounting */ |
4fadd7bb2 freeze_bdev: kill... |
940 941 942 943 944 945 |
mutex_lock(&bdev->bd_fsfreeze_mutex); if (bdev->bd_fsfreeze_count > 0) { mutex_unlock(&bdev->bd_fsfreeze_mutex); error = -EBUSY; goto error_bdev; } |
1da177e4c Linux-2.6.12-rc2 |
946 |
s = sget(fs_type, test_bdev_super, set_bdev_super, bdev); |
4fadd7bb2 freeze_bdev: kill... |
947 |
mutex_unlock(&bdev->bd_fsfreeze_mutex); |
1da177e4c Linux-2.6.12-rc2 |
948 |
if (IS_ERR(s)) |
454e2398b [PATCH] VFS: Perm... |
949 |
goto error_s; |
1da177e4c Linux-2.6.12-rc2 |
950 951 952 |
if (s->s_root) { if ((flags ^ s->s_flags) & MS_RDONLY) { |
74dbbdd7f New helper: deact... |
953 |
deactivate_locked_super(s); |
454e2398b [PATCH] VFS: Perm... |
954 955 |
error = -EBUSY; goto error_bdev; |
1da177e4c Linux-2.6.12-rc2 |
956 |
} |
454e2398b [PATCH] VFS: Perm... |
957 |
|
4f331f01b vfs: don't hold s... |
958 959 |
/* * s_umount nests inside bd_mutex during |
e525fd89d block: make blkde... |
960 961 962 963 |
* __invalidate_device(). blkdev_put() acquires * bd_mutex and can't be called under s_umount. Drop * s_umount temporarily. This is safe as we're * holding an active reference. |
4f331f01b vfs: don't hold s... |
964 965 |
*/ up_write(&s->s_umount); |
d4d776299 block: clean up b... |
966 |
blkdev_put(bdev, mode); |
4f331f01b vfs: don't hold s... |
967 |
down_write(&s->s_umount); |
1da177e4c Linux-2.6.12-rc2 |
968 969 |
} else { char b[BDEVNAME_SIZE]; |
9e1f1de02 more conservative... |
970 |
s->s_flags = flags | MS_NOSEC; |
30c40d2c0 [PATCH] propagate... |
971 |
s->s_mode = mode; |
1da177e4c Linux-2.6.12-rc2 |
972 |
strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); |
e78c9a004 [PATCH] fs: remov... |
973 |
sb_set_blocksize(s, block_size(bdev)); |
9b04c997b [PATCH] vfs: MS_V... |
974 |
error = fill_super(s, data, flags & MS_SILENT ? 1 : 0); |
1da177e4c Linux-2.6.12-rc2 |
975 |
if (error) { |
74dbbdd7f New helper: deact... |
976 |
deactivate_locked_super(s); |
454e2398b [PATCH] VFS: Perm... |
977 |
goto error; |
fa675765a Revert mount/umou... |
978 |
} |
454e2398b [PATCH] VFS: Perm... |
979 980 |
s->s_flags |= MS_ACTIVE; |
87d8fe1ee add releasepage h... |
981 |
bdev->bd_super = s; |
1da177e4c Linux-2.6.12-rc2 |
982 |
} |
152a08366 new helper: mount... |
983 |
return dget(s->s_root); |
1da177e4c Linux-2.6.12-rc2 |
984 |
|
454e2398b [PATCH] VFS: Perm... |
985 986 987 |
error_s: error = PTR_ERR(s); error_bdev: |
d4d776299 block: clean up b... |
988 |
blkdev_put(bdev, mode); |
454e2398b [PATCH] VFS: Perm... |
989 |
error: |
152a08366 new helper: mount... |
990 991 992 |
return ERR_PTR(error); } EXPORT_SYMBOL(mount_bdev); |
1da177e4c Linux-2.6.12-rc2 |
993 994 995 |
void kill_block_super(struct super_block *sb) { struct block_device *bdev = sb->s_bdev; |
30c40d2c0 [PATCH] propagate... |
996 |
fmode_t mode = sb->s_mode; |
1da177e4c Linux-2.6.12-rc2 |
997 |
|
ddbaaf302 NULL noise in fs/... |
998 |
bdev->bd_super = NULL; |
1da177e4c Linux-2.6.12-rc2 |
999 1000 |
generic_shutdown_super(sb); sync_blockdev(bdev); |
d4d776299 block: clean up b... |
1001 |
WARN_ON_ONCE(!(mode & FMODE_EXCL)); |
e525fd89d block: make blkde... |
1002 |
blkdev_put(bdev, mode | FMODE_EXCL); |
1da177e4c Linux-2.6.12-rc2 |
1003 1004 1005 |
} EXPORT_SYMBOL(kill_block_super); |
9361401eb [PATCH] BLOCK: Ma... |
1006 |
#endif |
1da177e4c Linux-2.6.12-rc2 |
1007 |
|
3c26ff6e4 convert get_sb_no... |
1008 |
struct dentry *mount_nodev(struct file_system_type *fs_type, |
1da177e4c Linux-2.6.12-rc2 |
1009 |
int flags, void *data, |
3c26ff6e4 convert get_sb_no... |
1010 |
int (*fill_super)(struct super_block *, void *, int)) |
1da177e4c Linux-2.6.12-rc2 |
1011 1012 1013 1014 1015 |
{ int error; struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL); if (IS_ERR(s)) |
3c26ff6e4 convert get_sb_no... |
1016 |
return ERR_CAST(s); |
1da177e4c Linux-2.6.12-rc2 |
1017 1018 |
s->s_flags = flags; |
9b04c997b [PATCH] vfs: MS_V... |
1019 |
error = fill_super(s, data, flags & MS_SILENT ? 1 : 0); |
1da177e4c Linux-2.6.12-rc2 |
1020 |
if (error) { |
74dbbdd7f New helper: deact... |
1021 |
deactivate_locked_super(s); |
3c26ff6e4 convert get_sb_no... |
1022 |
return ERR_PTR(error); |
1da177e4c Linux-2.6.12-rc2 |
1023 1024 |
} s->s_flags |= MS_ACTIVE; |
3c26ff6e4 convert get_sb_no... |
1025 |
return dget(s->s_root); |
1da177e4c Linux-2.6.12-rc2 |
1026 |
} |
3c26ff6e4 convert get_sb_no... |
1027 |
EXPORT_SYMBOL(mount_nodev); |
1da177e4c Linux-2.6.12-rc2 |
1028 1029 1030 1031 |
static int compare_single(struct super_block *s, void *p) { return 1; } |
fc14f2fef convert get_sb_si... |
1032 |
struct dentry *mount_single(struct file_system_type *fs_type, |
1da177e4c Linux-2.6.12-rc2 |
1033 |
int flags, void *data, |
fc14f2fef convert get_sb_si... |
1034 |
int (*fill_super)(struct super_block *, void *, int)) |
1da177e4c Linux-2.6.12-rc2 |
1035 1036 1037 1038 1039 1040 |
{ struct super_block *s; int error; s = sget(fs_type, compare_single, set_anon_super, NULL); if (IS_ERR(s)) |
fc14f2fef convert get_sb_si... |
1041 |
return ERR_CAST(s); |
1da177e4c Linux-2.6.12-rc2 |
1042 1043 |
if (!s->s_root) { s->s_flags = flags; |
9b04c997b [PATCH] vfs: MS_V... |
1044 |
error = fill_super(s, data, flags & MS_SILENT ? 1 : 0); |
1da177e4c Linux-2.6.12-rc2 |
1045 |
if (error) { |
74dbbdd7f New helper: deact... |
1046 |
deactivate_locked_super(s); |
fc14f2fef convert get_sb_si... |
1047 |
return ERR_PTR(error); |
1da177e4c Linux-2.6.12-rc2 |
1048 1049 |
} s->s_flags |= MS_ACTIVE; |
9329d1bea vfs: get_sb_singl... |
1050 1051 |
} else { do_remount_sb(s, flags, data, 0); |
1da177e4c Linux-2.6.12-rc2 |
1052 |
} |
fc14f2fef convert get_sb_si... |
1053 1054 1055 |
return dget(s->s_root); } EXPORT_SYMBOL(mount_single); |
9d412a43c vfs: split off vf... |
1056 1057 |
struct dentry * mount_fs(struct file_system_type *type, int flags, const char *name, void *data) |
1da177e4c Linux-2.6.12-rc2 |
1058 |
{ |
c96e41e92 beginning of tran... |
1059 |
struct dentry *root; |
9d412a43c vfs: split off vf... |
1060 |
struct super_block *sb; |
1da177e4c Linux-2.6.12-rc2 |
1061 |
char *secdata = NULL; |
9d412a43c vfs: split off vf... |
1062 |
int error = -ENOMEM; |
8089352a1 Mirror MS_KERNMOU... |
1063 |
|
e00075298 LSM/SELinux: Inte... |
1064 |
if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) { |
1da177e4c Linux-2.6.12-rc2 |
1065 |
secdata = alloc_secdata(); |
454e2398b [PATCH] VFS: Perm... |
1066 |
if (!secdata) |
9d412a43c vfs: split off vf... |
1067 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
1068 |
|
e00075298 LSM/SELinux: Inte... |
1069 |
error = security_sb_copy_data(data, secdata); |
454e2398b [PATCH] VFS: Perm... |
1070 |
if (error) |
1da177e4c Linux-2.6.12-rc2 |
1071 |
goto out_free_secdata; |
1da177e4c Linux-2.6.12-rc2 |
1072 |
} |
1a102ff92 vfs: bury ->get_sb() |
1073 1074 1075 1076 |
root = type->mount(type, flags, name, data); if (IS_ERR(root)) { error = PTR_ERR(root); goto out_free_secdata; |
c96e41e92 beginning of tran... |
1077 |
} |
9d412a43c vfs: split off vf... |
1078 1079 1080 |
sb = root->d_sb; BUG_ON(!sb); WARN_ON(!sb->s_bdi); |
6c5103890 Merge branch 'for... |
1081 |
WARN_ON(sb->s_bdi == &default_backing_dev_info); |
9d412a43c vfs: split off vf... |
1082 |
sb->s_flags |= MS_BORN; |
454e2398b [PATCH] VFS: Perm... |
1083 |
|
9d412a43c vfs: split off vf... |
1084 |
error = security_sb_kern_mount(sb, flags, secdata); |
5129a469a Catch filesystems... |
1085 1086 |
if (error) goto out_sb; |
454e2398b [PATCH] VFS: Perm... |
1087 |
|
42cb56ae2 vfs: change sb->s... |
1088 1089 1090 1091 |
/* * filesystems should never set s_maxbytes larger than MAX_LFS_FILESIZE * but s_maxbytes was an unsigned long long for many releases. Throw * this warning for a little while to try and catch filesystems that |
4358b5678 VFS: trivial: fix... |
1092 |
* violate this rule. |
42cb56ae2 vfs: change sb->s... |
1093 |
*/ |
9d412a43c vfs: split off vf... |
1094 1095 1096 |
WARN((sb->s_maxbytes < 0), "%s set sb->s_maxbytes to " "negative value (%lld) ", type->name, sb->s_maxbytes); |
42cb56ae2 vfs: change sb->s... |
1097 |
|
9d412a43c vfs: split off vf... |
1098 |
up_write(&sb->s_umount); |
8680e22f2 [PATCH] VFS: memo... |
1099 |
free_secdata(secdata); |
9d412a43c vfs: split off vf... |
1100 |
return root; |
1da177e4c Linux-2.6.12-rc2 |
1101 |
out_sb: |
9d412a43c vfs: split off vf... |
1102 1103 |
dput(root); deactivate_locked_super(sb); |
1da177e4c Linux-2.6.12-rc2 |
1104 1105 |
out_free_secdata: free_secdata(secdata); |
1da177e4c Linux-2.6.12-rc2 |
1106 |
out: |
454e2398b [PATCH] VFS: Perm... |
1107 |
return ERR_PTR(error); |
1da177e4c Linux-2.6.12-rc2 |
1108 |
} |
18e9e5104 Introduce freeze_... |
1109 |
/** |
7000d3c42 fs/super: fix ker... |
1110 1111 |
* freeze_super - lock the filesystem and force it into a consistent state * @sb: the super to lock |
18e9e5104 Introduce freeze_... |
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 |
* * Syncs the super to make sure the filesystem is consistent and calls the fs's * freeze_fs. Subsequent calls to this without first thawing the fs will return * -EBUSY. */ int freeze_super(struct super_block *sb) { int ret; atomic_inc(&sb->s_active); down_write(&sb->s_umount); if (sb->s_frozen) { deactivate_locked_super(sb); return -EBUSY; } |
dabe0dc19 vfs: fix the rest... |
1127 1128 1129 1130 |
if (!(sb->s_flags & MS_BORN)) { up_write(&sb->s_umount); return 0; /* sic - it's "nothing to do" */ } |
18e9e5104 Introduce freeze_... |
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 |
if (sb->s_flags & MS_RDONLY) { sb->s_frozen = SB_FREEZE_TRANS; smp_wmb(); up_write(&sb->s_umount); return 0; } sb->s_frozen = SB_FREEZE_WRITE; smp_wmb(); sync_filesystem(sb); sb->s_frozen = SB_FREEZE_TRANS; smp_wmb(); sync_blockdev(sb->s_bdev); if (sb->s_op->freeze_fs) { ret = sb->s_op->freeze_fs(sb); if (ret) { printk(KERN_ERR "VFS:Filesystem freeze failed "); sb->s_frozen = SB_UNFROZEN; deactivate_locked_super(sb); return ret; } } up_write(&sb->s_umount); return 0; } EXPORT_SYMBOL(freeze_super); /** * thaw_super -- unlock filesystem * @sb: the super to thaw * * Unlocks the filesystem and marks it writeable again after freeze_super(). */ int thaw_super(struct super_block *sb) { int error; down_write(&sb->s_umount); if (sb->s_frozen == SB_UNFROZEN) { up_write(&sb->s_umount); return -EINVAL; } if (sb->s_flags & MS_RDONLY) goto out; if (sb->s_op->unfreeze_fs) { error = sb->s_op->unfreeze_fs(sb); if (error) { printk(KERN_ERR "VFS:Filesystem thaw failed "); sb->s_frozen = SB_FREEZE_TRANS; up_write(&sb->s_umount); return error; } } out: sb->s_frozen = SB_UNFROZEN; smp_wmb(); wake_up(&sb->s_wait_unfrozen); deactivate_locked_super(sb); return 0; } EXPORT_SYMBOL(thaw_super); |