From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: [RFC 1/4] move /proc/filesystems inside /proc/self Date: Mon, 23 Jan 2012 20:56:09 +0400 Message-ID: <1327337772-1972-2-git-send-email-glommer@parallels.com> References: <1327337772-1972-1-git-send-email-glommer@parallels.com> Return-path: In-Reply-To: <1327337772-1972-1-git-send-email-glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, serge-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org, daniel.lezcano-GANU6spQydw@public.gmane.org, pjt-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, mzxreary-uLTowLwuiw4b1SvskN2V4Q@public.gmane.org, xemul-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org, James.Bottomley-d9PhHud1JfjCXq6kfMZ53/egYHeGw8Jk@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Glauber Costa This simple patch is a preparation for what is to come. It moves the list of available filesystems inside /proc/self/, linking /proc/filesystems to it. It effectively means that each process may have a different view of which filesystems are available in the system, depending on the namespace it lives. Signed-off-by: Glauber Costa --- fs/filesystems.c | 21 +-------------------- fs/proc/base.c | 15 +++++++++++++++ fs/proc/root.c | 1 + include/linux/fs.h | 2 ++ 4 files changed, 19 insertions(+), 20 deletions(-) diff --git a/fs/filesystems.c b/fs/filesystems.c index 0845f84..458d120 100644 --- a/fs/filesystems.c +++ b/fs/filesystems.c @@ -219,7 +219,7 @@ int __init get_filesystem_list(char *buf) } #ifdef CONFIG_PROC_FS -static int filesystems_proc_show(struct seq_file *m, void *v) +int filesystems_proc_show(struct seq_file *m, void *v) { struct file_system_type * tmp; @@ -234,25 +234,6 @@ static int filesystems_proc_show(struct seq_file *m, void *v) read_unlock(&file_systems_lock); return 0; } - -static int filesystems_proc_open(struct inode *inode, struct file *file) -{ - return single_open(file, filesystems_proc_show, NULL); -} - -static const struct file_operations filesystems_proc_fops = { - .open = filesystems_proc_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init proc_filesystems_init(void) -{ - proc_create("filesystems", 0, NULL, &filesystems_proc_fops); - return 0; -} -module_init(proc_filesystems_init); #endif static struct file_system_type *__get_fs_type(const char *name, int len) diff --git a/fs/proc/base.c b/fs/proc/base.c index 851ba3d..2a6e2c7 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2768,6 +2768,7 @@ static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, */ static const struct file_operations proc_task_operations; static const struct inode_operations proc_task_inode_operations; +static const struct file_operations filesystems_proc_fops; static const struct pid_entry tgid_base_stuff[] = { DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), @@ -2851,6 +2852,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_HARDWALL INF("hardwall", S_IRUGO, proc_pid_hardwall), #endif + REG("filesystems", S_IRUGO, filesystems_proc_fops), }; static int proc_tgid_base_readdir(struct file * filp, @@ -2871,6 +2873,18 @@ static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *de tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); } +static int filesystems_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, filesystems_proc_show, NULL); +} + +static const struct file_operations filesystems_proc_fops = { + .open = filesystems_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + static const struct inode_operations proc_tgid_base_inode_operations = { .lookup = proc_tgid_base_lookup, .getattr = pid_getattr, @@ -3193,6 +3207,7 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_HARDWALL INF("hardwall", S_IRUGO, proc_pid_hardwall), #endif + REG("filesystems", S_IRUGO, filesystems_proc_fops), }; static int proc_tid_base_readdir(struct file * filp, diff --git a/fs/proc/root.c b/fs/proc/root.c index 03102d9..87bf2e3 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -104,6 +104,7 @@ void __init proc_root_init(void) } proc_symlink("mounts", NULL, "self/mounts"); + proc_symlink("filesystems", NULL, "self/filesystems"); proc_net_init(); diff --git a/include/linux/fs.h b/include/linux/fs.h index e0bc4ff..3286d74 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2529,6 +2529,8 @@ extern int generic_block_fiemap(struct inode *inode, extern void get_filesystem(struct file_system_type *fs); extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); +extern int filesystems_proc_show(struct seq_file *m, void *v); + extern struct super_block *get_super(struct block_device *); extern struct super_block *get_active_super(struct block_device *bdev); extern struct super_block *user_get_super(dev_t); -- 1.7.7.4