X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=fs%2Fsysfs%2Fdir.c;h=9e95e7abaf699e88c585540373e59597295a1cfa;hb=958b7f37ee0fb2846c8d44310a68ae9605614ff9;hp=5f3d725d11251487481c57599bc0f0ddedcfe904;hpb=ebdea46fecae40c4d7effcd33f40918a37a1df4b;p=linux-2.6-omap-h63xx.git diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 5f3d725d112..9e95e7abaf6 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -9,6 +9,7 @@ #include #include #include +#include #include "sysfs.h" DECLARE_RWSEM(sysfs_rename_sem); @@ -32,25 +33,39 @@ static struct dentry_operations sysfs_dentry_ops = { /* * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent */ -static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent * parent_sd, - void * element) +static struct sysfs_dirent * __sysfs_new_dirent(void * element) { struct sysfs_dirent * sd; - sd = kmem_cache_alloc(sysfs_dir_cachep, GFP_KERNEL); + sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); if (!sd) return NULL; - memset(sd, 0, sizeof(*sd)); atomic_set(&sd->s_count, 1); atomic_set(&sd->s_event, 1); INIT_LIST_HEAD(&sd->s_children); - list_add(&sd->s_sibling, &parent_sd->s_children); + INIT_LIST_HEAD(&sd->s_sibling); sd->s_element = element; return sd; } +static void __sysfs_list_dirent(struct sysfs_dirent *parent_sd, + struct sysfs_dirent *sd) +{ + if (sd) + list_add(&sd->s_sibling, &parent_sd->s_children); +} + +static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent *parent_sd, + void * element) +{ + struct sysfs_dirent *sd; + sd = __sysfs_new_dirent(element); + __sysfs_list_dirent(parent_sd, sd); + return sd; +} + /* * * Return -EEXIST if there is already a sysfs element with the same name for @@ -77,14 +92,14 @@ int sysfs_dirent_exist(struct sysfs_dirent *parent_sd, } -int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, - void * element, umode_t mode, int type) +static struct sysfs_dirent * +__sysfs_make_dirent(struct dentry *dentry, void *element, mode_t mode, int type) { struct sysfs_dirent * sd; - sd = sysfs_new_dirent(parent_sd, element); + sd = __sysfs_new_dirent(element); if (!sd) - return -ENOMEM; + goto out; sd->s_mode = mode; sd->s_type = type; @@ -94,7 +109,19 @@ int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, dentry->d_op = &sysfs_dentry_ops; } - return 0; +out: + return sd; +} + +int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, + void * element, umode_t mode, int type) +{ + struct sysfs_dirent *sd; + + sd = __sysfs_make_dirent(dentry, element, mode, type); + __sysfs_list_dirent(parent_sd, sd); + + return sd ? 0 : -ENOMEM; } static int init_dir(struct inode * inode) @@ -103,7 +130,7 @@ static int init_dir(struct inode * inode) inode->i_fop = &sysfs_dir_operations; /* directory inodes start off with i_nlink == 2 (for "." entry) */ - inode->i_nlink++; + inc_nlink(inode); return 0; } @@ -137,7 +164,7 @@ static int create_dir(struct kobject * k, struct dentry * p, if (!error) { error = sysfs_create(*d, mode, init_dir); if (!error) { - p->d_inode->i_nlink++; + inc_nlink(p->d_inode); (*d)->d_op = &sysfs_dentry_ops; d_rehash(*d); } @@ -165,11 +192,11 @@ int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d) /** * sysfs_create_dir - create a directory for an object. - * @parent: parent parent object. * @kobj: object we're creating directory for. + * @shadow_parent: parent parent object. */ -int sysfs_create_dir(struct kobject * kobj) +int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent) { struct dentry * dentry = NULL; struct dentry * parent; @@ -177,7 +204,9 @@ int sysfs_create_dir(struct kobject * kobj) BUG_ON(!kobj); - if (kobj->parent) + if (shadow_parent) + parent = shadow_parent; + else if (kobj->parent) parent = kobj->parent->dentry; else if (sysfs_mount && sysfs_mount->mnt_sb) parent = sysfs_mount->mnt_sb->s_root; @@ -298,21 +327,12 @@ void sysfs_remove_subdir(struct dentry * d) } -/** - * 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) +static void __sysfs_remove_dir(struct dentry *dentry) { - struct dentry * dentry = dget(kobj->dentry); struct sysfs_dirent * parent_sd; struct sysfs_dirent * sd, * tmp; + dget(dentry); if (!dentry) return; @@ -333,32 +353,60 @@ void sysfs_remove_dir(struct kobject * kobj) * Drop reference from dget() on entrance. */ dput(dentry); +} + +/** + * 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) +{ + __sysfs_remove_dir(kobj->dentry); kobj->dentry = NULL; } -int sysfs_rename_dir(struct kobject * kobj, const char *new_name) +int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, + const char *new_name) { int error = 0; - struct dentry * new_dentry, * parent; - - if (!strcmp(kobject_name(kobj), new_name)) - return -EINVAL; + struct dentry * new_dentry; - if (!kobj->parent) - return -EINVAL; + if (!new_parent) + return -EFAULT; down_write(&sysfs_rename_sem); - parent = kobj->parent->dentry; + mutex_lock(&new_parent->d_inode->i_mutex); - mutex_lock(&parent->d_inode->i_mutex); - - new_dentry = lookup_one_len(new_name, parent, strlen(new_name)); + new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name)); if (!IS_ERR(new_dentry)) { - if (!new_dentry->d_inode) { + /* By allowing two different directories with the + * same d_parent we allow this routine to move + * between different shadows of the same directory + */ + if (kobj->dentry->d_parent->d_inode != new_parent->d_inode) + return -EINVAL; + else if (new_dentry->d_parent->d_inode != new_parent->d_inode) + error = -EINVAL; + else if (new_dentry == kobj->dentry) + error = -EINVAL; + else if (!new_dentry->d_inode) { error = kobject_set_name(kobj, "%s", new_name); if (!error) { + struct sysfs_dirent *sd, *parent_sd; + d_add(new_dentry, NULL); d_move(kobj->dentry, new_dentry); + + sd = kobj->dentry->d_fsdata; + parent_sd = new_parent->d_fsdata; + + list_del_init(&sd->s_sibling); + list_add(&sd->s_sibling, &parent_sd->s_children); } else d_drop(new_dentry); @@ -366,15 +414,58 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) error = -EEXIST; dput(new_dentry); } - mutex_unlock(&parent->d_inode->i_mutex); + mutex_unlock(&new_parent->d_inode->i_mutex); up_write(&sysfs_rename_sem); return error; } +int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent) +{ + struct dentry *old_parent_dentry, *new_parent_dentry, *new_dentry; + struct sysfs_dirent *new_parent_sd, *sd; + int error; + + old_parent_dentry = kobj->parent ? + kobj->parent->dentry : sysfs_mount->mnt_sb->s_root; + new_parent_dentry = new_parent ? + new_parent->dentry : sysfs_mount->mnt_sb->s_root; + +again: + mutex_lock(&old_parent_dentry->d_inode->i_mutex); + if (!mutex_trylock(&new_parent_dentry->d_inode->i_mutex)) { + mutex_unlock(&old_parent_dentry->d_inode->i_mutex); + goto again; + } + + new_parent_sd = new_parent_dentry->d_fsdata; + sd = kobj->dentry->d_fsdata; + + new_dentry = lookup_one_len(kobj->name, new_parent_dentry, + strlen(kobj->name)); + if (IS_ERR(new_dentry)) { + error = PTR_ERR(new_dentry); + goto out; + } else + error = 0; + d_add(new_dentry, NULL); + d_move(kobj->dentry, new_dentry); + dput(new_dentry); + + /* Remove from old parent's list and insert into new parent's list. */ + list_del_init(&sd->s_sibling); + list_add(&sd->s_sibling, &new_parent_sd->s_children); + +out: + mutex_unlock(&new_parent_dentry->d_inode->i_mutex); + mutex_unlock(&old_parent_dentry->d_inode->i_mutex); + + return error; +} + static int sysfs_dir_open(struct inode *inode, struct file *file) { - struct dentry * dentry = file->f_dentry; + struct dentry * dentry = file->f_path.dentry; struct sysfs_dirent * parent_sd = dentry->d_fsdata; mutex_lock(&dentry->d_inode->i_mutex); @@ -387,7 +478,7 @@ static int sysfs_dir_open(struct inode *inode, struct file *file) static int sysfs_dir_close(struct inode *inode, struct file *file) { - struct dentry * dentry = file->f_dentry; + struct dentry * dentry = file->f_path.dentry; struct sysfs_dirent * cursor = file->private_data; mutex_lock(&dentry->d_inode->i_mutex); @@ -407,7 +498,7 @@ static inline unsigned char dt_type(struct sysfs_dirent *sd) static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) { - struct dentry *dentry = filp->f_dentry; + struct dentry *dentry = filp->f_path.dentry; struct sysfs_dirent * parent_sd = dentry->d_fsdata; struct sysfs_dirent *cursor = filp->private_data; struct list_head *p, *q = &cursor->s_sibling; @@ -464,7 +555,7 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin) { - struct dentry * dentry = file->f_dentry; + struct dentry * dentry = file->f_path.dentry; mutex_lock(&dentry->d_inode->i_mutex); switch (origin) { @@ -474,7 +565,7 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin) if (offset >= 0) break; default: - mutex_unlock(&file->f_dentry->d_inode->i_mutex); + mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); return -EINVAL; } if (offset != file->f_pos) { @@ -502,6 +593,95 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin) return offset; } + +/** + * sysfs_make_shadowed_dir - Setup so a directory can be shadowed + * @kobj: object we're creating shadow of. + */ + +int sysfs_make_shadowed_dir(struct kobject *kobj, + void * (*follow_link)(struct dentry *, struct nameidata *)) +{ + struct inode *inode; + struct inode_operations *i_op; + + inode = kobj->dentry->d_inode; + if (inode->i_op != &sysfs_dir_inode_operations) + return -EINVAL; + + i_op = kmalloc(sizeof(*i_op), GFP_KERNEL); + if (!i_op) + return -ENOMEM; + + memcpy(i_op, &sysfs_dir_inode_operations, sizeof(*i_op)); + i_op->follow_link = follow_link; + + /* Locking of inode->i_op? + * Since setting i_op is a single word write and they + * are atomic we should be ok here. + */ + inode->i_op = i_op; + return 0; +} + +/** + * sysfs_create_shadow_dir - create a shadow directory for an object. + * @kobj: object we're creating directory for. + * + * sysfs_make_shadowed_dir must already have been called on this + * directory. + */ + +struct dentry *sysfs_create_shadow_dir(struct kobject *kobj) +{ + struct sysfs_dirent *sd; + struct dentry *parent, *dir, *shadow; + struct inode *inode; + + dir = kobj->dentry; + inode = dir->d_inode; + parent = dir->d_parent; + shadow = ERR_PTR(-EINVAL); + if (!sysfs_is_shadowed_inode(inode)) + goto out; + + shadow = d_alloc(parent, &dir->d_name); + if (!shadow) + goto nomem; + + sd = __sysfs_make_dirent(shadow, kobj, inode->i_mode, SYSFS_DIR); + if (!sd) + goto nomem; + + d_instantiate(shadow, igrab(inode)); + inc_nlink(inode); + inc_nlink(parent->d_inode); + shadow->d_op = &sysfs_dentry_ops; + + dget(shadow); /* Extra count - pin the dentry in core */ + +out: + return shadow; +nomem: + dput(shadow); + shadow = ERR_PTR(-ENOMEM); + goto out; +} + +/** + * sysfs_remove_shadow_dir - remove an object's directory. + * @shadow: dentry of shadow directory + * + * 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_shadow_dir(struct dentry *shadow) +{ + __sysfs_remove_dir(shadow); +} + const struct file_operations sysfs_dir_operations = { .open = sysfs_dir_open, .release = sysfs_dir_close,