diff options
| -rw-r--r-- | fs/kernfs/inode.c | 327 | ||||
| -rw-r--r-- | fs/kernfs/kernfs-internal.h | 13 | ||||
| -rw-r--r-- | fs/sysfs/Makefile | 2 | ||||
| -rw-r--r-- | fs/sysfs/inode.c | 342 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 13 |
5 files changed, 341 insertions, 356 deletions
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index 86bfeea..9d4fab4 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -7,3 +7,330 @@ * * This file is released under the GPLv2. */ + +#include <linux/pagemap.h> +#include <linux/backing-dev.h> +#include <linux/capability.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/xattr.h> +#include <linux/security.h> + +#include "kernfs-internal.h" + +static const struct address_space_operations sysfs_aops = { + .readpage = simple_readpage, + .write_begin = simple_write_begin, + .write_end = simple_write_end, +}; + +static struct backing_dev_info sysfs_backing_dev_info = { + .name = "sysfs", + .ra_pages = 0, /* No readahead */ + .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, +}; + +static const struct inode_operations sysfs_inode_operations = { + .permission = sysfs_permission, + .setattr = sysfs_setattr, + .getattr = sysfs_getattr, + .setxattr = sysfs_setxattr, +}; + +int __init sysfs_inode_init(void) +{ + return bdi_init(&sysfs_backing_dev_info); +} + +static struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) +{ + struct sysfs_inode_attrs *attrs; + struct iattr *iattrs; + + attrs = kzalloc(sizeof(struct sysfs_inode_attrs), GFP_KERNEL); + if (!attrs) + return NULL; + iattrs = &attrs->ia_iattr; + + /* assign default attributes */ + iattrs->ia_mode = sd->s_mode; + iattrs->ia_uid = GLOBAL_ROOT_UID; + iattrs->ia_gid = GLOBAL_ROOT_GID; + iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME; + + return attrs; +} + +static int __kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr) +{ + struct sysfs_inode_attrs *sd_attrs; + struct iattr *iattrs; + unsigned int ia_valid = iattr->ia_valid; + + sd_attrs = sd->s_iattr; + + if (!sd_attrs) { + /* setting attributes for the first time, allocate now */ + sd_attrs = sysfs_init_inode_attrs(sd); + if (!sd_attrs) + return -ENOMEM; + sd->s_iattr = sd_attrs; + } + /* attributes were changed at least once in past */ + iattrs = &sd_attrs->ia_iattr; + + if (ia_valid & ATTR_UID) + iattrs->ia_uid = iattr->ia_uid; + if (ia_valid & ATTR_GID) + iattrs->ia_gid = iattr->ia_gid; + if (ia_valid & ATTR_ATIME) + iattrs->ia_atime = iattr->ia_atime; + if (ia_valid & ATTR_MTIME) + iattrs->ia_mtime = iattr->ia_mtime; + if (ia_valid & ATTR_CTIME) + iattrs->ia_ctime = iattr->ia_ctime; + if (ia_valid & ATTR_MODE) { + umode_t mode = iattr->ia_mode; + iattrs->ia_mode = sd->s_mode = mode; + } + return 0; +} + +/** + * kernfs_setattr - set iattr on a node + * @sd: target node + * @iattr: iattr to set + * + * Returns 0 on success, -errno on failure. + */ +int kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr) +{ + int ret; + + mutex_lock(&sysfs_mutex); + ret = __kernfs_setattr(sd, iattr); + mutex_unlock(&sysfs_mutex); + return ret; +} + +int sysfs_setattr(struct dentry *dentry, struct iattr *iattr) +{ + struct inode *inode = dentry->d_inode; + struct sysfs_dirent *sd = dentry->d_fsdata; + int error; + + if (!sd) + return -EINVAL; + + mutex_lock(&sysfs_mutex); + error = inode_change_ok(inode, iattr); + if (error) + goto out; + + error = __kernfs_setattr(sd, iattr); + if (error) + goto out; + + /* this ignores size changes */ + setattr_copy(inode, iattr); + +out: + mutex_unlock(&sysfs_mutex); + return error; +} + +static int sysfs_sd_setsecdata(struct sysfs_dirent *sd, void **secdata, + u32 *secdata_len) +{ + struct sysfs_inode_attrs *iattrs; + void *old_secdata; + size_t old_secdata_len; + + if (!sd->s_iattr) { + sd->s_iattr = sysfs_init_inode_attrs(sd); + if (!sd->s_iattr) + return -ENOMEM; + } + + iattrs = sd->s_iattr; + old_secdata = iattrs->ia_secdata; + old_secdata_len = iattrs->ia_secdata_len; + + iattrs->ia_secdata = *secdata; + iattrs->ia_secdata_len = *secdata_len; + + *secdata = old_secdata; + *secdata_len = old_secdata_len; + return 0; +} + +int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, + size_t size, int flags) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + void *secdata; + int error; + u32 secdata_len = 0; + + if (!sd) + return -EINVAL; + + if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { + const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; + error = security_inode_setsecurity(dentry->d_inode, suffix, + value, size, flags); + if (error) + goto out; + error = security_inode_getsecctx(dentry->d_inode, + &secdata, &secdata_len); + if (error) + goto out; + + mutex_lock(&sysfs_mutex); + error = sysfs_sd_setsecdata(sd, &secdata, &secdata_len); + mutex_unlock(&sysfs_mutex); + + if (secdata) + security_release_secctx(secdata, secdata_len); + } else + return -EINVAL; +out: + return error; +} + +static inline void set_default_inode_attr(struct inode *inode, umode_t mode) +{ + inode->i_mode = mode; + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; +} + +static inline void set_inode_attr(struct inode *inode, struct iattr *iattr) +{ + inode->i_uid = iattr->ia_uid; + inode->i_gid = iattr->ia_gid; + inode->i_atime = iattr->ia_atime; + inode->i_mtime = iattr->ia_mtime; + inode->i_ctime = iattr->ia_ctime; +} + +static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode) +{ + struct sysfs_inode_attrs *iattrs = sd->s_iattr; + + inode->i_mode = sd->s_mode; + if (iattrs) { + /* sysfs_dirent has non-default attributes + * get them from persistent copy in sysfs_dirent + */ + set_inode_attr(inode, &iattrs->ia_iattr); + security_inode_notifysecctx(inode, + iattrs->ia_secdata, + iattrs->ia_secdata_len); + } + + if (sysfs_type(sd) == SYSFS_DIR) + set_nlink(inode, sd->s_dir.subdirs + 2); +} + +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + struct inode *inode = dentry->d_inode; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + generic_fillattr(inode, stat); + return 0; +} + +static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) +{ + kernfs_get(sd); + inode->i_private = sd; + inode->i_mapping->a_ops = &sysfs_aops; + inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; + inode->i_op = &sysfs_inode_operations; + + set_default_inode_attr(inode, sd->s_mode); + sysfs_refresh_inode(sd, inode); + + /* initialize inode according to type */ + switch (sysfs_type(sd)) { + case SYSFS_DIR: + inode->i_op = &sysfs_dir_inode_operations; + inode->i_fop = &sysfs_dir_operations; + break; + case SYSFS_KOBJ_ATTR: + inode->i_size = sd->s_attr.size; + inode->i_fop = &kernfs_file_operations; + break; + case SYSFS_KOBJ_LINK: + inode->i_op = &sysfs_symlink_inode_operations; + break; + default: + BUG(); + } + + unlock_new_inode(inode); +} + +/** + * sysfs_get_inode - get inode for sysfs_dirent + * @sb: super block + * @sd: sysfs_dirent to allocate inode for + * + * Get inode for @sd. If such inode doesn't exist, a new inode + * is allocated and basics are initialized. New inode is + * returned locked. + * + * LOCKING: + * Kernel thread context (may sleep). + * + * RETURNS: + * Pointer to allocated inode on success, NULL on failure. + */ +struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd) +{ + struct inode *inode; + + inode = iget_locked(sb, sd->s_ino); + if (inode && (inode->i_state & I_NEW)) + sysfs_init_inode(sd, inode); + + return inode; +} + +/* + * The sysfs_dirent serves as both an inode and a directory entry for sysfs. + * To prevent the sysfs inode numbers from being freed prematurely we take a + * reference to sysfs_dirent from the sysfs inode. A + * super_operations.evict_inode() implementation is needed to drop that + * reference upon inode destruction. + */ +void sysfs_evict_inode(struct inode *inode) +{ + struct sysfs_dirent *sd = inode->i_private; + + truncate_inode_pages(&inode->i_data, 0); + clear_inode(inode); + kernfs_put(sd); +} + +int sysfs_permission(struct inode *inode, int mask) +{ + struct sysfs_dirent *sd; + + if (mask & MAY_NOT_BLOCK) + return -ECHILD; + + sd = inode->i_private; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + return generic_permission(inode, mask); +} diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h index 5a2c3a1..933ac8d 100644 --- a/fs/kernfs/kernfs-internal.h +++ b/fs/kernfs/kernfs-internal.h @@ -112,4 +112,17 @@ struct sysfs_addrm_cxt { #include "../sysfs/sysfs.h" +/* + * inode.c + */ +struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd); +void sysfs_evict_inode(struct inode *inode); +int sysfs_permission(struct inode *inode, int mask); +int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat); +int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, + size_t size, int flags); +int sysfs_inode_init(void); + #endif /* __KERNFS_INTERNAL_H */ diff --git a/fs/sysfs/Makefile b/fs/sysfs/Makefile index 8876ac1..6eff6e1 100644 --- a/fs/sysfs/Makefile +++ b/fs/sysfs/Makefile @@ -2,4 +2,4 @@ # Makefile for the sysfs virtual filesystem # -obj-y := inode.o file.o dir.o symlink.o mount.o group.o +obj-y := file.o dir.o symlink.o mount.o group.o diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c deleted file mode 100644 index bfe4478..0000000 --- a/fs/sysfs/inode.c +++ /dev/null @@ -1,342 +0,0 @@ -/* - * fs/sysfs/inode.c - basic sysfs inode and dentry operations - * - * 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/pagemap.h> -#include <linux/namei.h> -#include <linux/backing-dev.h> -#include <linux/capability.h> -#include <linux/errno.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/sysfs.h> -#include <linux/xattr.h> -#include <linux/security.h> -#include "sysfs.h" - -static const struct address_space_operations sysfs_aops = { - .readpage = simple_readpage, - .write_begin = simple_write_begin, - .write_end = simple_write_end, -}; - -static struct backing_dev_info sysfs_backing_dev_info = { - .name = "sysfs", - .ra_pages = 0, /* No readahead */ - .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, -}; - -static const struct inode_operations sysfs_inode_operations = { - .permission = sysfs_permission, - .setattr = sysfs_setattr, - .getattr = sysfs_getattr, - .setxattr = sysfs_setxattr, -}; - -int __init sysfs_inode_init(void) -{ - return bdi_init(&sysfs_backing_dev_info); -} - -static struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) -{ - struct sysfs_inode_attrs *attrs; - struct iattr *iattrs; - - attrs = kzalloc(sizeof(struct sysfs_inode_attrs), GFP_KERNEL); - if (!attrs) - return NULL; - iattrs = &attrs->ia_iattr; - - /* assign default attributes */ - iattrs->ia_mode = sd->s_mode; - iattrs->ia_uid = GLOBAL_ROOT_UID; - iattrs->ia_gid = GLOBAL_ROOT_GID; - iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME; - - return attrs; -} - -static int __kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr) -{ - struct sysfs_inode_attrs *sd_attrs; - struct iattr *iattrs; - unsigned int ia_valid = iattr->ia_valid; - - sd_attrs = sd->s_iattr; - - if (!sd_attrs) { - /* setting attributes for the first time, allocate now */ - sd_attrs = sysfs_init_inode_attrs(sd); - if (!sd_attrs) - return -ENOMEM; - sd->s_iattr = sd_attrs; - } - /* attributes were changed at least once in past */ - iattrs = &sd_attrs->ia_iattr; - - if (ia_valid & ATTR_UID) - iattrs->ia_uid = iattr->ia_uid; - if (ia_valid & ATTR_GID) - iattrs->ia_gid = iattr->ia_gid; - if (ia_valid & ATTR_ATIME) - iattrs->ia_atime = iattr->ia_atime; - if (ia_valid & ATTR_MTIME) - iattrs->ia_mtime = iattr->ia_mtime; - if (ia_valid & ATTR_CTIME) - iattrs->ia_ctime = iattr->ia_ctime; - if (ia_valid & ATTR_MODE) { - umode_t mode = iattr->ia_mode; - iattrs->ia_mode = sd->s_mode = mode; - } - return 0; -} - -/** - * kernfs_setattr - set iattr on a node - * @sd: target node - * @iattr: iattr to set - * - * Returns 0 on success, -errno on failure. - */ -int kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr) -{ - int ret; - - mutex_lock(&sysfs_mutex); - ret = __kernfs_setattr(sd, iattr); - mutex_unlock(&sysfs_mutex); - return ret; -} - -int sysfs_setattr(struct dentry *dentry, struct iattr *iattr) -{ - struct inode *inode = dentry->d_inode; - struct sysfs_dirent *sd = dentry->d_fsdata; - int error; - - if (!sd) - return -EINVAL; - - mutex_lock(&sysfs_mutex); - error = inode_change_ok(inode, iattr); - if (error) - goto out; - - error = __kernfs_setattr(sd, iattr); - if (error) - goto out; - - /* this ignores size changes */ - setattr_copy(inode, iattr); - -out: - mutex_unlock(&sysfs_mutex); - return error; -} - -static int sysfs_sd_setsecdata(struct sysfs_dirent *sd, void **secdata, - u32 *secdata_len) -{ - struct sysfs_inode_attrs *iattrs; - void *old_secdata; - size_t old_secdata_len; - - if (!sd->s_iattr) { - sd->s_iattr = sysfs_init_inode_attrs(sd); - if (!sd->s_iattr) - return -ENOMEM; - } - - iattrs = sd->s_iattr; - old_secdata = iattrs->ia_secdata; - old_secdata_len = iattrs->ia_secdata_len; - - iattrs->ia_secdata = *secdata; - iattrs->ia_secdata_len = *secdata_len; - - *secdata = old_secdata; - *secdata_len = old_secdata_len; - return 0; -} - -int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags) -{ - struct sysfs_dirent *sd = dentry->d_fsdata; - void *secdata; - int error; - u32 secdata_len = 0; - - if (!sd) - return -EINVAL; - - if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { - const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; - error = security_inode_setsecurity(dentry->d_inode, suffix, - value, size, flags); - if (error) - goto out; - error = security_inode_getsecctx(dentry->d_inode, - &secdata, &secdata_len); - if (error) - goto out; - - mutex_lock(&sysfs_mutex); - error = sysfs_sd_setsecdata(sd, &secdata, &secdata_len); - mutex_unlock(&sysfs_mutex); - - if (secdata) - security_release_secctx(secdata, secdata_len); - } else - return -EINVAL; -out: - return error; -} - -static inline void set_default_inode_attr(struct inode *inode, umode_t mode) -{ - inode->i_mode = mode; - inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; -} - -static inline void set_inode_attr(struct inode *inode, struct iattr *iattr) -{ - inode->i_uid = iattr->ia_uid; - inode->i_gid = iattr->ia_gid; - inode->i_atime = iattr->ia_atime; - inode->i_mtime = iattr->ia_mtime; - inode->i_ctime = iattr->ia_ctime; -} - -static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode) -{ - struct sysfs_inode_attrs *iattrs = sd->s_iattr; - - inode->i_mode = sd->s_mode; - if (iattrs) { - /* sysfs_dirent has non-default attributes - * get them from persistent copy in sysfs_dirent - */ - set_inode_attr(inode, &iattrs->ia_iattr); - security_inode_notifysecctx(inode, - iattrs->ia_secdata, - iattrs->ia_secdata_len); - } - - if (sysfs_type(sd) == SYSFS_DIR) - set_nlink(inode, sd->s_dir.subdirs + 2); -} - -int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, - struct kstat *stat) -{ - struct sysfs_dirent *sd = dentry->d_fsdata; - struct inode *inode = dentry->d_inode; - - mutex_lock(&sysfs_mutex); - sysfs_refresh_inode(sd, inode); - mutex_unlock(&sysfs_mutex); - - generic_fillattr(inode, stat); - return 0; -} - -static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) -{ - kernfs_get(sd); - inode->i_private = sd; - inode->i_mapping->a_ops = &sysfs_aops; - inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; - inode->i_op = &sysfs_inode_operations; - - set_default_inode_attr(inode, sd->s_mode); - sysfs_refresh_inode(sd, inode); - - /* initialize inode according to type */ - switch (sysfs_type(sd)) { - case SYSFS_DIR: - inode->i_op = &sysfs_dir_inode_operations; - inode->i_fop = &sysfs_dir_operations; - break; - case SYSFS_KOBJ_ATTR: - inode->i_size = sd->s_attr.size; - inode->i_fop = &kernfs_file_operations; - break; - case SYSFS_KOBJ_LINK: - inode->i_op = &sysfs_symlink_inode_operations; - break; - default: - BUG(); - } - - unlock_new_inode(inode); -} - -/** - * sysfs_get_inode - get inode for sysfs_dirent - * @sb: super block - * @sd: sysfs_dirent to allocate inode for - * - * Get inode for @sd. If such inode doesn't exist, a new inode - * is allocated and basics are initialized. New inode is - * returned locked. - * - * LOCKING: - * Kernel thread context (may sleep). - * - * RETURNS: - * Pointer to allocated inode on success, NULL on failure. - */ -struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd) -{ - struct inode *inode; - - inode = iget_locked(sb, sd->s_ino); - if (inode && (inode->i_state & I_NEW)) - sysfs_init_inode(sd, inode); - - return inode; -} - -/* - * The sysfs_dirent serves as both an inode and a directory entry for sysfs. - * To prevent the sysfs inode numbers from being freed prematurely we take a - * reference to sysfs_dirent from the sysfs inode. A - * super_operations.evict_inode() implementation is needed to drop that - * reference upon inode destruction. - */ -void sysfs_evict_inode(struct inode *inode) -{ - struct sysfs_dirent *sd = inode->i_private; - - truncate_inode_pages(&inode->i_data, 0); - clear_inode(inode); - kernfs_put(sd); -} - -int sysfs_permission(struct inode *inode, int mask) -{ - struct sysfs_dirent *sd; - - if (mask & MAY_NOT_BLOCK) - return -ECHILD; - - sd = inode->i_private; - - mutex_lock(&sysfs_mutex); - sysfs_refresh_inode(sd, inode); - mutex_unlock(&sysfs_mutex); - - return generic_permission(inode, mask); -} diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index f8c936f..93c1910 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -52,19 +52,6 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt); struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); /* - * inode.c - */ -struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd); -void sysfs_evict_inode(struct inode *inode); -int sysfs_permission(struct inode *inode, int mask); -int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); -int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, - struct kstat *stat); -int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags); -int sysfs_inode_init(void); - -/* * file.c */ extern const struct file_operations kernfs_file_operations; |
