diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/sysfs/dir.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/sysfs/dir.c | 1049 |
1 files changed, 0 insertions, 1049 deletions
diff --git a/ANDROID_3.4.5/fs/sysfs/dir.c b/ANDROID_3.4.5/fs/sysfs/dir.c deleted file mode 100644 index 35a36d39..00000000 --- a/ANDROID_3.4.5/fs/sysfs/dir.c +++ /dev/null @@ -1,1049 +0,0 @@ -/* - * fs/sysfs/dir.c - sysfs core and dir operation implementation - * - * Copyright (c) 2001-3 Patrick Mochel - * Copyright (c) 2007 SUSE Linux Products GmbH - * Copyright (c) 2007 Tejun Heo <teheo@suse.de> - * - * This file is released under the GPLv2. - * - * Please see Documentation/filesystems/sysfs.txt for more information. - */ - -#undef DEBUG - -#include <linux/fs.h> -#include <linux/mount.h> -#include <linux/module.h> -#include <linux/kobject.h> -#include <linux/namei.h> -#include <linux/idr.h> -#include <linux/completion.h> -#include <linux/mutex.h> -#include <linux/slab.h> -#include <linux/security.h> -#include <linux/hash.h> -#include "sysfs.h" - -DEFINE_MUTEX(sysfs_mutex); -DEFINE_SPINLOCK(sysfs_assoc_lock); - -#define to_sysfs_dirent(X) rb_entry((X), struct sysfs_dirent, s_rb); - -static DEFINE_SPINLOCK(sysfs_ino_lock); -static DEFINE_IDA(sysfs_ino_ida); - -/** - * sysfs_name_hash - * @ns: Namespace tag to hash - * @name: Null terminated string to hash - * - * Returns 31 bit hash of ns + name (so it fits in an off_t ) - */ -static unsigned int sysfs_name_hash(const void *ns, const char *name) -{ - unsigned long hash = init_name_hash(); - unsigned int len = strlen(name); - while (len--) - hash = partial_name_hash(*name++, hash); - hash = ( end_name_hash(hash) ^ hash_ptr( (void *)ns, 31 ) ); - hash &= 0x7fffffffU; - /* Reserve hash numbers 0, 1 and INT_MAX for magic directory entries */ - if (hash < 1) - hash += 2; - if (hash >= INT_MAX) - hash = INT_MAX - 1; - return hash; -} - -static int sysfs_name_compare(unsigned int hash, const void *ns, - const char *name, const struct sysfs_dirent *sd) -{ - if (hash != sd->s_hash) - return hash - sd->s_hash; - if (ns != sd->s_ns) - return ns - sd->s_ns; - return strcmp(name, sd->s_name); -} - -static int sysfs_sd_compare(const struct sysfs_dirent *left, - const struct sysfs_dirent *right) -{ - return sysfs_name_compare(left->s_hash, left->s_ns, left->s_name, - right); -} - -/** - * sysfs_link_subling - link sysfs_dirent into sibling rbtree - * @sd: sysfs_dirent of interest - * - * Link @sd into its sibling rbtree which starts from - * sd->s_parent->s_dir.children. - * - * Locking: - * mutex_lock(sysfs_mutex) - * - * RETURNS: - * 0 on susccess -EEXIST on failure. - */ -static int sysfs_link_sibling(struct sysfs_dirent *sd) -{ - struct rb_node **node = &sd->s_parent->s_dir.children.rb_node; - struct rb_node *parent = NULL; - - if (sysfs_type(sd) == SYSFS_DIR) - sd->s_parent->s_dir.subdirs++; - - while (*node) { - struct sysfs_dirent *pos; - int result; - - pos = to_sysfs_dirent(*node); - parent = *node; - result = sysfs_sd_compare(sd, pos); - if (result < 0) - node = &pos->s_rb.rb_left; - else if (result > 0) - node = &pos->s_rb.rb_right; - else - return -EEXIST; - } - /* add new node and rebalance the tree */ - rb_link_node(&sd->s_rb, parent, node); - rb_insert_color(&sd->s_rb, &sd->s_parent->s_dir.children); - return 0; -} - -/** - * sysfs_unlink_sibling - unlink sysfs_dirent from sibling rbtree - * @sd: sysfs_dirent of interest - * - * Unlink @sd from its sibling rbtree which starts from - * sd->s_parent->s_dir.children. - * - * Locking: - * mutex_lock(sysfs_mutex) - */ -static void sysfs_unlink_sibling(struct sysfs_dirent *sd) -{ - if (sysfs_type(sd) == SYSFS_DIR) - sd->s_parent->s_dir.subdirs--; - - rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children); -} - -/** - * sysfs_get_active - get an active reference to sysfs_dirent - * @sd: sysfs_dirent to get an active reference to - * - * Get an active reference of @sd. This function is noop if @sd - * is NULL. - * - * RETURNS: - * Pointer to @sd on success, NULL on failure. - */ -struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) -{ - if (unlikely(!sd)) - return NULL; - - while (1) { - int v, t; - - v = atomic_read(&sd->s_active); - if (unlikely(v < 0)) - return NULL; - - t = atomic_cmpxchg(&sd->s_active, v, v + 1); - if (likely(t == v)) { - rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_); - return sd; - } - if (t < 0) - return NULL; - - cpu_relax(); - } -} - -/** - * sysfs_put_active - put an active reference to sysfs_dirent - * @sd: sysfs_dirent to put an active reference to - * - * Put an active reference to @sd. This function is noop if @sd - * is NULL. - */ -void sysfs_put_active(struct sysfs_dirent *sd) -{ - int v; - - if (unlikely(!sd)) - return; - - rwsem_release(&sd->dep_map, 1, _RET_IP_); - v = atomic_dec_return(&sd->s_active); - if (likely(v != SD_DEACTIVATED_BIAS)) - return; - - /* atomic_dec_return() is a mb(), we'll always see the updated - * sd->u.completion. - */ - complete(sd->u.completion); -} - -/** - * sysfs_deactivate - deactivate sysfs_dirent - * @sd: sysfs_dirent to deactivate - * - * Deny new active references and drain existing ones. - */ -static void sysfs_deactivate(struct sysfs_dirent *sd) -{ - DECLARE_COMPLETION_ONSTACK(wait); - int v; - - BUG_ON(!(sd->s_flags & SYSFS_FLAG_REMOVED)); - - if (!(sysfs_type(sd) & SYSFS_ACTIVE_REF)) - return; - - sd->u.completion = (void *)&wait; - - rwsem_acquire(&sd->dep_map, 0, 0, _RET_IP_); - /* atomic_add_return() is a mb(), put_active() will always see - * the updated sd->u.completion. - */ - v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); - - if (v != SD_DEACTIVATED_BIAS) { - lock_contended(&sd->dep_map, _RET_IP_); - wait_for_completion(&wait); - } - - lock_acquired(&sd->dep_map, _RET_IP_); - rwsem_release(&sd->dep_map, 1, _RET_IP_); -} - -static int sysfs_alloc_ino(unsigned int *pino) -{ - int ino, rc; - - retry: - spin_lock(&sysfs_ino_lock); - rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); - spin_unlock(&sysfs_ino_lock); - - if (rc == -EAGAIN) { - if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) - goto retry; - rc = -ENOMEM; - } - - *pino = ino; - return rc; -} - -static void sysfs_free_ino(unsigned int ino) -{ - spin_lock(&sysfs_ino_lock); - ida_remove(&sysfs_ino_ida, ino); - spin_unlock(&sysfs_ino_lock); -} - -void release_sysfs_dirent(struct sysfs_dirent * sd) -{ - struct sysfs_dirent *parent_sd; - - repeat: - /* Moving/renaming is always done while holding reference. - * sd->s_parent won't change beneath us. - */ - parent_sd = sd->s_parent; - - if (sysfs_type(sd) == SYSFS_KOBJ_LINK) - sysfs_put(sd->s_symlink.target_sd); - if (sysfs_type(sd) & SYSFS_COPY_NAME) - kfree(sd->s_name); - if (sd->s_iattr && sd->s_iattr->ia_secdata) - security_release_secctx(sd->s_iattr->ia_secdata, - sd->s_iattr->ia_secdata_len); - kfree(sd->s_iattr); - sysfs_free_ino(sd->s_ino); - kmem_cache_free(sysfs_dir_cachep, sd); - - sd = parent_sd; - if (sd && atomic_dec_and_test(&sd->s_count)) - goto repeat; -} - -static int sysfs_dentry_delete(const struct dentry *dentry) -{ - struct sysfs_dirent *sd = dentry->d_fsdata; - return !!(sd->s_flags & SYSFS_FLAG_REMOVED); -} - -static int sysfs_dentry_revalidate(struct dentry *dentry, struct nameidata *nd) -{ - struct sysfs_dirent *sd; - int is_dir; - - if (nd->flags & LOOKUP_RCU) - return -ECHILD; - - sd = dentry->d_fsdata; - mutex_lock(&sysfs_mutex); - - /* The sysfs dirent has been deleted */ - if (sd->s_flags & SYSFS_FLAG_REMOVED) - goto out_bad; - - /* The sysfs dirent has been moved? */ - if (dentry->d_parent->d_fsdata != sd->s_parent) - goto out_bad; - - /* The sysfs dirent has been renamed */ - if (strcmp(dentry->d_name.name, sd->s_name) != 0) - goto out_bad; - - mutex_unlock(&sysfs_mutex); -out_valid: - return 1; -out_bad: - /* Remove the dentry from the dcache hashes. - * If this is a deleted dentry we use d_drop instead of d_delete - * so sysfs doesn't need to cope with negative dentries. - * - * If this is a dentry that has simply been renamed we - * use d_drop to remove it from the dcache lookup on its - * old parent. If this dentry persists later when a lookup - * is performed at its new name the dentry will be readded - * to the dcache hashes. - */ - is_dir = (sysfs_type(sd) == SYSFS_DIR); - mutex_unlock(&sysfs_mutex); - if (is_dir) { - /* If we have submounts we must allow the vfs caches - * to lie about the state of the filesystem to prevent - * leaks and other nasty things. - */ - if (have_submounts(dentry)) - goto out_valid; - shrink_dcache_parent(dentry); - } - d_drop(dentry); - return 0; -} - -static void sysfs_dentry_iput(struct dentry *dentry, struct inode *inode) -{ - struct sysfs_dirent * sd = dentry->d_fsdata; - - sysfs_put(sd); - iput(inode); -} - -static const struct dentry_operations sysfs_dentry_ops = { - .d_revalidate = sysfs_dentry_revalidate, - .d_delete = sysfs_dentry_delete, - .d_iput = sysfs_dentry_iput, -}; - -struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) -{ - char *dup_name = NULL; - struct sysfs_dirent *sd; - - if (type & SYSFS_COPY_NAME) { - name = dup_name = kstrdup(name, GFP_KERNEL); - if (!name) - return NULL; - } - - sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); - if (!sd) - goto err_out1; - - if (sysfs_alloc_ino(&sd->s_ino)) - goto err_out2; - - atomic_set(&sd->s_count, 1); - atomic_set(&sd->s_active, 0); - - sd->s_name = name; - sd->s_mode = mode; - sd->s_flags = type; - - return sd; - - err_out2: - kmem_cache_free(sysfs_dir_cachep, sd); - err_out1: - kfree(dup_name); - return NULL; -} - -/** - * sysfs_addrm_start - prepare for sysfs_dirent add/remove - * @acxt: pointer to sysfs_addrm_cxt to be used - * @parent_sd: parent sysfs_dirent - * - * This function is called when the caller is about to add or - * remove sysfs_dirent under @parent_sd. This function acquires - * sysfs_mutex. @acxt is used to keep and pass context to - * other addrm functions. - * - * LOCKING: - * Kernel thread context (may sleep). sysfs_mutex is locked on - * return. - */ -void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, - struct sysfs_dirent *parent_sd) -{ - memset(acxt, 0, sizeof(*acxt)); - acxt->parent_sd = parent_sd; - - mutex_lock(&sysfs_mutex); -} - -/** - * __sysfs_add_one - add sysfs_dirent to parent without warning - * @acxt: addrm context to use - * @sd: sysfs_dirent to be added - * - * Get @acxt->parent_sd and set sd->s_parent to it and increment - * nlink of parent inode if @sd is a directory and link into the - * children list of the parent. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - * - * RETURNS: - * 0 on success, -EEXIST if entry with the given name already - * exists. - */ -int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) -{ - struct sysfs_inode_attrs *ps_iattr; - int ret; - - if (!!sysfs_ns_type(acxt->parent_sd) != !!sd->s_ns) { - WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - sysfs_ns_type(acxt->parent_sd)? "required": "invalid", - acxt->parent_sd->s_name, sd->s_name); - return -EINVAL; - } - - sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name); - sd->s_parent = sysfs_get(acxt->parent_sd); - - ret = sysfs_link_sibling(sd); - if (ret) - return ret; - - /* Update timestamps on the parent */ - ps_iattr = acxt->parent_sd->s_iattr; - if (ps_iattr) { - struct iattr *ps_iattrs = &ps_iattr->ia_iattr; - ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; - } - - return 0; -} - -/** - * sysfs_pathname - return full path to sysfs dirent - * @sd: sysfs_dirent whose path we want - * @path: caller allocated buffer - * - * Gives the name "/" to the sysfs_root entry; any path returned - * is relative to wherever sysfs is mounted. - * - * XXX: does no error checking on @path size - */ -static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) -{ - if (sd->s_parent) { - sysfs_pathname(sd->s_parent, path); - strcat(path, "/"); - } - strcat(path, sd->s_name); - return path; -} - -/** - * sysfs_add_one - add sysfs_dirent to parent - * @acxt: addrm context to use - * @sd: sysfs_dirent to be added - * - * Get @acxt->parent_sd and set sd->s_parent to it and increment - * nlink of parent inode if @sd is a directory and link into the - * children list of the parent. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - * - * RETURNS: - * 0 on success, -EEXIST if entry with the given name already - * exists. - */ -int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) -{ - int ret; - - ret = __sysfs_add_one(acxt, sd); - if (ret == -EEXIST) { - char *path = kzalloc(PATH_MAX, GFP_KERNEL); - WARN(1, KERN_WARNING - "sysfs: cannot create duplicate filename '%s'\n", - (path == NULL) ? sd->s_name : - strcat(strcat(sysfs_pathname(acxt->parent_sd, path), "/"), - sd->s_name)); - kfree(path); - } - - return ret; -} - -/** - * sysfs_remove_one - remove sysfs_dirent from parent - * @acxt: addrm context to use - * @sd: sysfs_dirent to be removed - * - * Mark @sd removed and drop nlink of parent inode if @sd is a - * directory. @sd is unlinked from the children list. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - */ -void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) -{ - struct sysfs_inode_attrs *ps_iattr; - - BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); - - sysfs_unlink_sibling(sd); - - /* Update timestamps on the parent */ - ps_iattr = acxt->parent_sd->s_iattr; - if (ps_iattr) { - struct iattr *ps_iattrs = &ps_iattr->ia_iattr; - ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; - } - - sd->s_flags |= SYSFS_FLAG_REMOVED; - sd->u.removed_list = acxt->removed; - acxt->removed = sd; -} - -/** - * sysfs_addrm_finish - finish up sysfs_dirent add/remove - * @acxt: addrm context to finish up - * - * Finish up sysfs_dirent add/remove. Resources acquired by - * sysfs_addrm_start() are released and removed sysfs_dirents are - * cleaned up. - * - * LOCKING: - * sysfs_mutex is released. - */ -void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) -{ - /* release resources acquired by sysfs_addrm_start() */ - mutex_unlock(&sysfs_mutex); - - /* kill removed sysfs_dirents */ - while (acxt->removed) { - struct sysfs_dirent *sd = acxt->removed; - - acxt->removed = sd->u.removed_list; - - sysfs_deactivate(sd); - unmap_bin_file(sd); - sysfs_put(sd); - } -} - -/** - * sysfs_find_dirent - find sysfs_dirent with the given name - * @parent_sd: sysfs_dirent to search under - * @name: name to look for - * - * Look for sysfs_dirent with name @name under @parent_sd. - * - * LOCKING: - * mutex_lock(sysfs_mutex) - * - * RETURNS: - * Pointer to sysfs_dirent if found, NULL if not. - */ -struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, - const void *ns, - const unsigned char *name) -{ - struct rb_node *node = parent_sd->s_dir.children.rb_node; - unsigned int hash; - - if (!!sysfs_ns_type(parent_sd) != !!ns) { - WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - sysfs_ns_type(parent_sd)? "required": "invalid", - parent_sd->s_name, name); - return NULL; - } - - hash = sysfs_name_hash(ns, name); - while (node) { - struct sysfs_dirent *sd; - int result; - - sd = to_sysfs_dirent(node); - result = sysfs_name_compare(hash, ns, name, sd); - if (result < 0) - node = node->rb_left; - else if (result > 0) - node = node->rb_right; - else - return sd; - } - return NULL; -} - -/** - * sysfs_get_dirent - find and get sysfs_dirent with the given name - * @parent_sd: sysfs_dirent to search under - * @name: name to look for - * - * Look for sysfs_dirent with name @name under @parent_sd and get - * it if found. - * - * LOCKING: - * Kernel thread context (may sleep). Grabs sysfs_mutex. - * - * RETURNS: - * Pointer to sysfs_dirent if found, NULL if not. - */ -struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, - const void *ns, - const unsigned char *name) -{ - struct sysfs_dirent *sd; - - mutex_lock(&sysfs_mutex); - sd = sysfs_find_dirent(parent_sd, ns, name); - sysfs_get(sd); - mutex_unlock(&sysfs_mutex); - - return sd; -} -EXPORT_SYMBOL_GPL(sysfs_get_dirent); - -static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, - enum kobj_ns_type type, const void *ns, const char *name, - struct sysfs_dirent **p_sd) -{ - umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; - struct sysfs_addrm_cxt acxt; - struct sysfs_dirent *sd; - int rc; - - /* allocate */ - sd = sysfs_new_dirent(name, mode, SYSFS_DIR); - if (!sd) - return -ENOMEM; - - sd->s_flags |= (type << SYSFS_NS_TYPE_SHIFT); - sd->s_ns = ns; - sd->s_dir.kobj = kobj; - - /* link in */ - sysfs_addrm_start(&acxt, parent_sd); - rc = sysfs_add_one(&acxt, sd); - sysfs_addrm_finish(&acxt); - - if (rc == 0) - *p_sd = sd; - else - sysfs_put(sd); - - return rc; -} - -int sysfs_create_subdir(struct kobject *kobj, const char *name, - struct sysfs_dirent **p_sd) -{ - return create_dir(kobj, kobj->sd, - KOBJ_NS_TYPE_NONE, NULL, name, p_sd); -} - -/** - * sysfs_read_ns_type: return associated ns_type - * @kobj: the kobject being queried - * - * Each kobject can be tagged with exactly one namespace type - * (i.e. network or user). Return the ns_type associated with - * this object if any - */ -static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) -{ - const struct kobj_ns_type_operations *ops; - enum kobj_ns_type type; - - ops = kobj_child_ns_ops(kobj); - if (!ops) - return KOBJ_NS_TYPE_NONE; - - type = ops->type; - BUG_ON(type <= KOBJ_NS_TYPE_NONE); - BUG_ON(type >= KOBJ_NS_TYPES); - BUG_ON(!kobj_ns_type_registered(type)); - - return type; -} - -/** - * sysfs_create_dir - create a directory for an object. - * @kobj: object we're creating directory for. - */ -int sysfs_create_dir(struct kobject * kobj) -{ - enum kobj_ns_type type; - struct sysfs_dirent *parent_sd, *sd; - const void *ns = NULL; - int error = 0; - - BUG_ON(!kobj); - - if (kobj->parent) - parent_sd = kobj->parent->sd; - else - parent_sd = &sysfs_root; - - if (!parent_sd) - return -ENOENT; - - if (sysfs_ns_type(parent_sd)) - ns = kobj->ktype->namespace(kobj); - type = sysfs_read_ns_type(kobj); - - error = create_dir(kobj, parent_sd, type, ns, kobject_name(kobj), &sd); - if (!error) - kobj->sd = sd; - return error; -} - -static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, - struct nameidata *nd) -{ - struct dentry *ret = NULL; - struct dentry *parent = dentry->d_parent; - struct sysfs_dirent *parent_sd = parent->d_fsdata; - struct sysfs_dirent *sd; - struct inode *inode; - enum kobj_ns_type type; - const void *ns; - - mutex_lock(&sysfs_mutex); - - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dir->i_sb)->ns[type]; - - sd = sysfs_find_dirent(parent_sd, ns, dentry->d_name.name); - - /* no such entry */ - if (!sd) { - ret = ERR_PTR(-ENOENT); - goto out_unlock; - } - - /* attach dentry and inode */ - inode = sysfs_get_inode(dir->i_sb, sd); - if (!inode) { - ret = ERR_PTR(-ENOMEM); - goto out_unlock; - } - - /* instantiate and hash dentry */ - ret = d_find_alias(inode); - if (!ret) { - d_set_d_op(dentry, &sysfs_dentry_ops); - dentry->d_fsdata = sysfs_get(sd); - d_add(dentry, inode); - } else { - d_move(ret, dentry); - iput(inode); - } - - out_unlock: - mutex_unlock(&sysfs_mutex); - return ret; -} - -const struct inode_operations sysfs_dir_inode_operations = { - .lookup = sysfs_lookup, - .permission = sysfs_permission, - .setattr = sysfs_setattr, - .getattr = sysfs_getattr, - .setxattr = sysfs_setxattr, -}; - -static void remove_dir(struct sysfs_dirent *sd) -{ - struct sysfs_addrm_cxt acxt; - - sysfs_addrm_start(&acxt, sd->s_parent); - sysfs_remove_one(&acxt, sd); - sysfs_addrm_finish(&acxt); -} - -void sysfs_remove_subdir(struct sysfs_dirent *sd) -{ - remove_dir(sd); -} - - -static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) -{ - struct sysfs_addrm_cxt acxt; - struct rb_node *pos; - - if (!dir_sd) - return; - - pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); - sysfs_addrm_start(&acxt, dir_sd); - pos = rb_first(&dir_sd->s_dir.children); - while (pos) { - struct sysfs_dirent *sd = to_sysfs_dirent(pos); - pos = rb_next(pos); - if (sysfs_type(sd) != SYSFS_DIR) - sysfs_remove_one(&acxt, sd); - } - sysfs_addrm_finish(&acxt); - - remove_dir(dir_sd); -} - -/** - * sysfs_remove_dir - remove an object's directory. - * @kobj: object. - * - * The only thing special about this is that we remove any files in - * the directory before we remove the directory, and we've inlined - * what used to be sysfs_rmdir() below, instead of calling separately. - */ - -void sysfs_remove_dir(struct kobject * kobj) -{ - struct sysfs_dirent *sd = kobj->sd; - - spin_lock(&sysfs_assoc_lock); - kobj->sd = NULL; - spin_unlock(&sysfs_assoc_lock); - - __sysfs_remove_dir(sd); -} - -int sysfs_rename(struct sysfs_dirent *sd, - struct sysfs_dirent *new_parent_sd, const void *new_ns, - const char *new_name) -{ - const char *dup_name = NULL; - int error; - - mutex_lock(&sysfs_mutex); - - error = 0; - if ((sd->s_parent == new_parent_sd) && (sd->s_ns == new_ns) && - (strcmp(sd->s_name, new_name) == 0)) - goto out; /* nothing to rename */ - - error = -EEXIST; - if (sysfs_find_dirent(new_parent_sd, new_ns, new_name)) - goto out; - - /* rename sysfs_dirent */ - if (strcmp(sd->s_name, new_name) != 0) { - error = -ENOMEM; - new_name = dup_name = kstrdup(new_name, GFP_KERNEL); - if (!new_name) - goto out; - - dup_name = sd->s_name; - sd->s_name = new_name; - } - - /* Move to the appropriate place in the appropriate directories rbtree. */ - sysfs_unlink_sibling(sd); - sysfs_get(new_parent_sd); - sysfs_put(sd->s_parent); - sd->s_ns = new_ns; - sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name); - sd->s_parent = new_parent_sd; - sysfs_link_sibling(sd); - - error = 0; - out: - mutex_unlock(&sysfs_mutex); - kfree(dup_name); - return error; -} - -int sysfs_rename_dir(struct kobject *kobj, const char *new_name) -{ - struct sysfs_dirent *parent_sd = kobj->sd->s_parent; - const void *new_ns = NULL; - - if (sysfs_ns_type(parent_sd)) - new_ns = kobj->ktype->namespace(kobj); - - return sysfs_rename(kobj->sd, parent_sd, new_ns, new_name); -} - -int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) -{ - struct sysfs_dirent *sd = kobj->sd; - struct sysfs_dirent *new_parent_sd; - const void *new_ns = NULL; - - BUG_ON(!sd->s_parent); - if (sysfs_ns_type(sd->s_parent)) - new_ns = kobj->ktype->namespace(kobj); - new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? - new_parent_kobj->sd : &sysfs_root; - - return sysfs_rename(sd, new_parent_sd, new_ns, sd->s_name); -} - -/* Relationship between s_mode and the DT_xxx types */ -static inline unsigned char dt_type(struct sysfs_dirent *sd) -{ - return (sd->s_mode >> 12) & 15; -} - -static int sysfs_dir_release(struct inode *inode, struct file *filp) -{ - sysfs_put(filp->private_data); - return 0; -} - -static struct sysfs_dirent *sysfs_dir_pos(const void *ns, - struct sysfs_dirent *parent_sd, loff_t hash, struct sysfs_dirent *pos) -{ - if (pos) { - int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) && - pos->s_parent == parent_sd && - hash == pos->s_hash; - sysfs_put(pos); - if (!valid) - pos = NULL; - } - if (!pos && (hash > 1) && (hash < INT_MAX)) { - struct rb_node *node = parent_sd->s_dir.children.rb_node; - while (node) { - pos = to_sysfs_dirent(node); - - if (hash < pos->s_hash) - node = node->rb_left; - else if (hash > pos->s_hash) - node = node->rb_right; - else - break; - } - } - /* Skip over entries in the wrong namespace */ - while (pos && pos->s_ns != ns) { - struct rb_node *node = rb_next(&pos->s_rb); - if (!node) - pos = NULL; - else - pos = to_sysfs_dirent(node); - } - return pos; -} - -static struct sysfs_dirent *sysfs_dir_next_pos(const void *ns, - struct sysfs_dirent *parent_sd, ino_t ino, struct sysfs_dirent *pos) -{ - pos = sysfs_dir_pos(ns, parent_sd, ino, pos); - if (pos) do { - struct rb_node *node = rb_next(&pos->s_rb); - if (!node) - pos = NULL; - else - pos = to_sysfs_dirent(node); - } while (pos && pos->s_ns != ns); - return pos; -} - -static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) -{ - struct dentry *dentry = filp->f_path.dentry; - struct sysfs_dirent * parent_sd = dentry->d_fsdata; - struct sysfs_dirent *pos = filp->private_data; - enum kobj_ns_type type; - const void *ns; - ino_t ino; - - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dentry->d_sb)->ns[type]; - - if (filp->f_pos == 0) { - ino = parent_sd->s_ino; - if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0) - filp->f_pos++; - } - if (filp->f_pos == 1) { - if (parent_sd->s_parent) - ino = parent_sd->s_parent->s_ino; - else - ino = parent_sd->s_ino; - if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) - filp->f_pos++; - } - mutex_lock(&sysfs_mutex); - for (pos = sysfs_dir_pos(ns, parent_sd, filp->f_pos, pos); - pos; - pos = sysfs_dir_next_pos(ns, parent_sd, filp->f_pos, pos)) { - const char * name; - unsigned int type; - int len, ret; - - name = pos->s_name; - len = strlen(name); - ino = pos->s_ino; - type = dt_type(pos); - filp->f_pos = pos->s_hash; - filp->private_data = sysfs_get(pos); - - mutex_unlock(&sysfs_mutex); - ret = filldir(dirent, name, len, filp->f_pos, ino, type); - mutex_lock(&sysfs_mutex); - if (ret < 0) - break; - } - mutex_unlock(&sysfs_mutex); - if ((filp->f_pos > 1) && !pos) { /* EOF */ - filp->f_pos = INT_MAX; - filp->private_data = NULL; - } - return 0; -} - - -const struct file_operations sysfs_dir_operations = { - .read = generic_read_dir, - .readdir = sysfs_readdir, - .release = sysfs_dir_release, - .llseek = generic_file_llseek, -}; |