diff options
Diffstat (limited to 'fs/debugfs')
| -rw-r--r-- | fs/debugfs/file.c | 18 | ||||
| -rw-r--r-- | fs/debugfs/inode.c | 69 |
2 files changed, 66 insertions, 21 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index 7d162b0efbf0..ddb3fc258df9 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -147,7 +147,7 @@ static int debugfs_locked_down(struct inode *inode, struct file *filp, const struct file_operations *real_fops) { - if ((inode->i_mode & 07777) == 0444 && + if ((inode->i_mode & 07777 & ~0444) == 0 && !(filp->f_mode & FMODE_WRITE) && !real_fops->unlocked_ioctl && !real_fops->compat_ioctl && @@ -1121,7 +1121,7 @@ void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, } EXPORT_SYMBOL_GPL(debugfs_print_regs32); -static int debugfs_show_regset32(struct seq_file *s, void *data) +static int debugfs_regset32_show(struct seq_file *s, void *data) { struct debugfs_regset32 *regset = s->private; @@ -1136,17 +1136,7 @@ static int debugfs_show_regset32(struct seq_file *s, void *data) return 0; } -static int debugfs_open_regset32(struct inode *inode, struct file *file) -{ - return single_open(file, debugfs_show_regset32, inode->i_private); -} - -static const struct file_operations fops_regset32 = { - .open = debugfs_open_regset32, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; +DEFINE_SHOW_ATTRIBUTE(debugfs_regset32); /** * debugfs_create_regset32 - create a debugfs file that returns register values @@ -1167,7 +1157,7 @@ void debugfs_create_regset32(const char *name, umode_t mode, struct dentry *parent, struct debugfs_regset32 *regset) { - debugfs_create_file(name, mode, parent, regset, &fops_regset32); + debugfs_create_file(name, mode, parent, regset, &debugfs_regset32_fops); } EXPORT_SYMBOL_GPL(debugfs_create_regset32); diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 2f117c57160d..2e8e112b1993 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -82,6 +82,8 @@ struct debugfs_mount_opts { kuid_t uid; kgid_t gid; umode_t mode; + /* Opt_* bitfield. */ + unsigned int opts; }; enum { @@ -111,6 +113,7 @@ static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts) kgid_t gid; char *p; + opts->opts = 0; opts->mode = DEBUGFS_DEFAULT_MODE; while ((p = strsep(&data, ",")) != NULL) { @@ -145,24 +148,44 @@ static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts) * but traditionally debugfs has ignored all mount options */ } + + opts->opts |= BIT(token); } return 0; } -static int debugfs_apply_options(struct super_block *sb) +static void _debugfs_apply_options(struct super_block *sb, bool remount) { struct debugfs_fs_info *fsi = sb->s_fs_info; struct inode *inode = d_inode(sb->s_root); struct debugfs_mount_opts *opts = &fsi->mount_opts; - inode->i_mode &= ~S_IALLUGO; - inode->i_mode |= opts->mode; + /* + * On remount, only reset mode/uid/gid if they were provided as mount + * options. + */ - inode->i_uid = opts->uid; - inode->i_gid = opts->gid; + if (!remount || opts->opts & BIT(Opt_mode)) { + inode->i_mode &= ~S_IALLUGO; + inode->i_mode |= opts->mode; + } - return 0; + if (!remount || opts->opts & BIT(Opt_uid)) + inode->i_uid = opts->uid; + + if (!remount || opts->opts & BIT(Opt_gid)) + inode->i_gid = opts->gid; +} + +static void debugfs_apply_options(struct super_block *sb) +{ + _debugfs_apply_options(sb, false); +} + +static void debugfs_apply_options_remount(struct super_block *sb) +{ + _debugfs_apply_options(sb, true); } static int debugfs_remount(struct super_block *sb, int *flags, char *data) @@ -175,7 +198,7 @@ static int debugfs_remount(struct super_block *sb, int *flags, char *data) if (err) goto fail; - debugfs_apply_options(sb); + debugfs_apply_options_remount(sb); fail: return err; @@ -450,6 +473,11 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode, * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. + * + * NOTE: it's expected that most callers should _ignore_ the errors returned + * by this function. Other debugfs functions handle the fact that the "dentry" + * passed to them could be an error and they don't crash in that case. + * Drivers should generally work fine even if debugfs fails to init anyway. */ struct dentry *debugfs_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, @@ -551,6 +579,11 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_size); * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. + * + * NOTE: it's expected that most callers should _ignore_ the errors returned + * by this function. Other debugfs functions handle the fact that the "dentry" + * passed to them could be an error and they don't crash in that case. + * Drivers should generally work fine even if debugfs fails to init anyway. */ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) { @@ -735,6 +768,28 @@ void debugfs_remove(struct dentry *dentry) EXPORT_SYMBOL_GPL(debugfs_remove); /** + * debugfs_lookup_and_remove - lookup a directory or file and recursively remove it + * @name: a pointer to a string containing the name of the item to look up. + * @parent: a pointer to the parent dentry of the item. + * + * This is the equlivant of doing something like + * debugfs_remove(debugfs_lookup(..)) but with the proper reference counting + * handled for the directory being looked up. + */ +void debugfs_lookup_and_remove(const char *name, struct dentry *parent) +{ + struct dentry *dentry; + + dentry = debugfs_lookup(name, parent); + if (!dentry) + return; + + debugfs_remove(dentry); + dput(dentry); +} +EXPORT_SYMBOL_GPL(debugfs_lookup_and_remove); + +/** * debugfs_rename - rename a file/directory in the debugfs filesystem * @old_dir: a pointer to the parent dentry for the renamed object. This * should be a directory dentry. |