diff options
author | Ingo Molnar <mingo@kernel.org> | 2015-02-28 08:03:10 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2015-02-28 08:03:10 +0100 |
commit | 5838d18955b52467f4b30486e62a31727b39998d (patch) | |
tree | 8aeb8412156bab93a6b39f2de4a8d6c912ddb31a /fs/debugfs/inode.c | |
parent | 579deee571a755c485ad702ef82c77a98a2ccc05 (diff) | |
parent | 895c8b7b4623d4f55e260e5dee2574b4f7113105 (diff) |
Merge branch 'linus' into x86/urgent, to merge dependent patch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'fs/debugfs/inode.c')
-rw-r--r-- | fs/debugfs/inode.c | 327 |
1 files changed, 186 insertions, 141 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 05f2960ed7c3..96400ab42d13 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -34,93 +34,16 @@ static struct vfsmount *debugfs_mount; static int debugfs_mount_count; static bool debugfs_registered; -static struct inode *debugfs_get_inode(struct super_block *sb, umode_t mode, dev_t dev, - void *data, const struct file_operations *fops) - +static struct inode *debugfs_get_inode(struct super_block *sb) { struct inode *inode = new_inode(sb); - if (inode) { inode->i_ino = get_next_ino(); - inode->i_mode = mode; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; - switch (mode & S_IFMT) { - default: - init_special_inode(inode, mode, dev); - break; - case S_IFREG: - inode->i_fop = fops ? fops : &debugfs_file_operations; - inode->i_private = data; - break; - case S_IFLNK: - inode->i_op = &debugfs_link_operations; - inode->i_private = data; - break; - case S_IFDIR: - inode->i_op = &simple_dir_inode_operations; - inode->i_fop = &simple_dir_operations; - - /* directory inodes start off with i_nlink == 2 - * (for "." entry) */ - inc_nlink(inode); - break; - } } return inode; } -/* SMP-safe */ -static int debugfs_mknod(struct inode *dir, struct dentry *dentry, - umode_t mode, dev_t dev, void *data, - const struct file_operations *fops) -{ - struct inode *inode; - int error = -EPERM; - - if (dentry->d_inode) - return -EEXIST; - - inode = debugfs_get_inode(dir->i_sb, mode, dev, data, fops); - if (inode) { - d_instantiate(dentry, inode); - dget(dentry); - error = 0; - } - return error; -} - -static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) -{ - int res; - - mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR; - res = debugfs_mknod(dir, dentry, mode, 0, NULL, NULL); - if (!res) { - inc_nlink(dir); - fsnotify_mkdir(dir, dentry); - } - return res; -} - -static int debugfs_link(struct inode *dir, struct dentry *dentry, umode_t mode, - void *data) -{ - mode = (mode & S_IALLUGO) | S_IFLNK; - return debugfs_mknod(dir, dentry, mode, 0, data, NULL); -} - -static int debugfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, - void *data, const struct file_operations *fops) -{ - int res; - - mode = (mode & S_IALLUGO) | S_IFREG; - res = debugfs_mknod(dir, dentry, mode, 0, data, fops); - if (!res) - fsnotify_create(dir, dentry); - return res; -} - static inline int debugfs_positive(struct dentry *dentry) { return dentry->d_inode && !d_unhashed(dentry); @@ -246,10 +169,31 @@ static int debugfs_show_options(struct seq_file *m, struct dentry *root) return 0; } +static void debugfs_evict_inode(struct inode *inode) +{ + truncate_inode_pages_final(&inode->i_data); + clear_inode(inode); + if (S_ISLNK(inode->i_mode)) + kfree(inode->i_private); +} + static const struct super_operations debugfs_super_operations = { .statfs = simple_statfs, .remount_fs = debugfs_remount, .show_options = debugfs_show_options, + .evict_inode = debugfs_evict_inode, +}; + +static struct vfsmount *debugfs_automount(struct path *path) +{ + struct vfsmount *(*f)(void *); + f = (struct vfsmount *(*)(void *))path->dentry->d_fsdata; + return f(path->dentry->d_inode->i_private); +} + +static const struct dentry_operations debugfs_dops = { + .d_delete = always_delete_dentry, + .d_automount = debugfs_automount, }; static int debug_fill_super(struct super_block *sb, void *data, int silent) @@ -276,6 +220,7 @@ static int debug_fill_super(struct super_block *sb, void *data, int silent) goto fail; sb->s_op = &debugfs_super_operations; + sb->s_d_op = &debugfs_dops; debugfs_apply_options(sb); @@ -302,11 +247,9 @@ static struct file_system_type debug_fs_type = { }; MODULE_ALIAS_FS("debugfs"); -static struct dentry *__create_file(const char *name, umode_t mode, - struct dentry *parent, void *data, - const struct file_operations *fops) +static struct dentry *start_creating(const char *name, struct dentry *parent) { - struct dentry *dentry = NULL; + struct dentry *dentry; int error; pr_debug("debugfs: creating file '%s'\n",name); @@ -314,7 +257,7 @@ static struct dentry *__create_file(const char *name, umode_t mode, error = simple_pin_fs(&debug_fs_type, &debugfs_mount, &debugfs_mount_count); if (error) - goto exit; + return ERR_PTR(error); /* If the parent is not specified, we create it in the root. * We need the root dentry to do this, which is in the super @@ -326,31 +269,26 @@ static struct dentry *__create_file(const char *name, umode_t mode, mutex_lock(&parent->d_inode->i_mutex); dentry = lookup_one_len(name, parent, strlen(name)); - if (!IS_ERR(dentry)) { - switch (mode & S_IFMT) { - case S_IFDIR: - error = debugfs_mkdir(parent->d_inode, dentry, mode); - - break; - case S_IFLNK: - error = debugfs_link(parent->d_inode, dentry, mode, - data); - break; - default: - error = debugfs_create(parent->d_inode, dentry, mode, - data, fops); - break; - } + if (!IS_ERR(dentry) && dentry->d_inode) { dput(dentry); - } else - error = PTR_ERR(dentry); - mutex_unlock(&parent->d_inode->i_mutex); - - if (error) { - dentry = NULL; - simple_release_fs(&debugfs_mount, &debugfs_mount_count); + dentry = ERR_PTR(-EEXIST); } -exit: + if (IS_ERR(dentry)) + mutex_unlock(&parent->d_inode->i_mutex); + return dentry; +} + +static struct dentry *failed_creating(struct dentry *dentry) +{ + mutex_unlock(&dentry->d_parent->d_inode->i_mutex); + dput(dentry); + simple_release_fs(&debugfs_mount, &debugfs_mount_count); + return NULL; +} + +static struct dentry *end_creating(struct dentry *dentry) +{ + mutex_unlock(&dentry->d_parent->d_inode->i_mutex); return dentry; } @@ -384,19 +322,71 @@ struct dentry *debugfs_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops) { - switch (mode & S_IFMT) { - case S_IFREG: - case 0: - break; - default: - BUG(); - } + struct dentry *dentry; + struct inode *inode; + + if (!(mode & S_IFMT)) + mode |= S_IFREG; + BUG_ON(!S_ISREG(mode)); + dentry = start_creating(name, parent); + + if (IS_ERR(dentry)) + return NULL; + + inode = debugfs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); - return __create_file(name, mode, parent, data, fops); + inode->i_mode = mode; + inode->i_fop = fops ? fops : &debugfs_file_operations; + inode->i_private = data; + d_instantiate(dentry, inode); + fsnotify_create(dentry->d_parent->d_inode, dentry); + return end_creating(dentry); } EXPORT_SYMBOL_GPL(debugfs_create_file); /** + * debugfs_create_file_size - create a file in the debugfs filesystem + * @name: a pointer to a string containing the name of the file to create. + * @mode: the permission that the file should have. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * file will be created in the root of the debugfs filesystem. + * @data: a pointer to something that the caller will want to get to later + * on. The inode.i_private pointer will point to this value on + * the open() call. + * @fops: a pointer to a struct file_operations that should be used for + * this file. + * @file_size: initial file size + * + * This is the basic "create a file" function for debugfs. It allows for a + * wide range of flexibility in creating a file, or a directory (if you want + * to create a directory, the debugfs_create_dir() function is + * recommended to be used instead.) + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the debugfs_remove() function when the file is + * to be removed (no automatic cleanup happens if your module is unloaded, + * you are responsible here.) If an error occurs, %NULL will be returned. + * + * If debugfs is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *debugfs_create_file_size(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops, + loff_t file_size) +{ + struct dentry *de = debugfs_create_file(name, mode, parent, data, fops); + + if (de) + de->d_inode->i_size = file_size; + return de; +} +EXPORT_SYMBOL_GPL(debugfs_create_file_size); + +/** * debugfs_create_dir - create a directory in the debugfs filesystem * @name: a pointer to a string containing the name of the directory to * create. @@ -416,12 +406,65 @@ EXPORT_SYMBOL_GPL(debugfs_create_file); */ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) { - return __create_file(name, S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO, - parent, NULL, NULL); + struct dentry *dentry = start_creating(name, parent); + struct inode *inode; + + if (IS_ERR(dentry)) + return NULL; + + inode = debugfs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); + + inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; + inode->i_op = &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + + /* directory inodes start off with i_nlink == 2 (for "." entry) */ + inc_nlink(inode); + d_instantiate(dentry, inode); + inc_nlink(dentry->d_parent->d_inode); + fsnotify_mkdir(dentry->d_parent->d_inode, dentry); + return end_creating(dentry); } EXPORT_SYMBOL_GPL(debugfs_create_dir); /** + * debugfs_create_automount - create automount point in the debugfs filesystem + * @name: a pointer to a string containing the name of the file to create. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * file will be created in the root of the debugfs filesystem. + * @f: function to be called when pathname resolution steps on that one. + * @data: opaque argument to pass to f(). + * + * @f should return what ->d_automount() would. + */ +struct dentry *debugfs_create_automount(const char *name, + struct dentry *parent, + struct vfsmount *(*f)(void *), + void *data) +{ + struct dentry *dentry = start_creating(name, parent); + struct inode *inode; + + if (IS_ERR(dentry)) + return NULL; + + inode = debugfs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); + + inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; + inode->i_flags |= S_AUTOMOUNT; + inode->i_private = data; + dentry->d_fsdata = (void *)f; + d_instantiate(dentry, inode); + return end_creating(dentry); +} +EXPORT_SYMBOL(debugfs_create_automount); + +/** * debugfs_create_symlink- create a symbolic link in the debugfs filesystem * @name: a pointer to a string containing the name of the symbolic link to * create. @@ -447,17 +490,28 @@ EXPORT_SYMBOL_GPL(debugfs_create_dir); struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, const char *target) { - struct dentry *result; - char *link; - - link = kstrdup(target, GFP_KERNEL); + struct dentry *dentry; + struct inode *inode; + char *link = kstrdup(target, GFP_KERNEL); if (!link) return NULL; - result = __create_file(name, S_IFLNK | S_IRWXUGO, parent, link, NULL); - if (!result) + dentry = start_creating(name, parent); + if (IS_ERR(dentry)) { kfree(link); - return result; + return NULL; + } + + inode = debugfs_get_inode(dentry->d_sb); + if (unlikely(!inode)) { + kfree(link); + return failed_creating(dentry); + } + inode->i_mode = S_IFLNK | S_IRWXUGO; + inode->i_op = &debugfs_link_operations; + inode->i_private = link; + d_instantiate(dentry, inode); + return end_creating(dentry); } EXPORT_SYMBOL_GPL(debugfs_create_symlink); @@ -466,23 +520,14 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent) int ret = 0; if (debugfs_positive(dentry)) { - if (dentry->d_inode) { - dget(dentry); - switch (dentry->d_inode->i_mode & S_IFMT) { - case S_IFDIR: - ret = simple_rmdir(parent->d_inode, dentry); - break; - case S_IFLNK: - kfree(dentry->d_inode->i_private); - /* fall through */ - default: - simple_unlink(parent->d_inode, dentry); - break; - } - if (!ret) - d_delete(dentry); - dput(dentry); - } + dget(dentry); + if (S_ISDIR(dentry->d_inode->i_mode)) + ret = simple_rmdir(parent->d_inode, dentry); + else + simple_unlink(parent->d_inode, dentry); + if (!ret) + d_delete(dentry); + dput(dentry); } return ret; } @@ -645,7 +690,7 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, } d_move(old_dentry, dentry); fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, - S_ISDIR(old_dentry->d_inode->i_mode), + d_is_dir(old_dentry), NULL, old_dentry); fsnotify_oldname_free(old_name); unlock_rename(new_dir, old_dir); |