summaryrefslogtreecommitdiff
path: root/fs/mount.h
diff options
context:
space:
mode:
authorYann Droneaud <ydroneaud@opteya.com>2015-06-30 14:57:30 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-30 19:44:56 -0700
commitede1bf0dcff2b07001c760992b1ca18fd0f419bc (patch)
tree924a682aa9fa0d076840edc178521d15abacfcf5 /fs/mount.h
parent0e1cc95b4cc7293bb7b39175035e7f7e45c90977 (diff)
downloadlwn-ede1bf0dcff2b07001c760992b1ca18fd0f419bc.tar.gz
lwn-ede1bf0dcff2b07001c760992b1ca18fd0f419bc.zip
fs: use seq_open_private() for proc_mounts
A patchset to remove support for passing pre-allocated struct seq_file to seq_open(). Such feature is undocumented and prone to error. In particular, if seq_release() is used in release handler, it will kfree() a pointer which was not allocated by seq_open(). So this patchset drops support for pre-allocated struct seq_file: it's only of use in proc_namespace.c and can be easily replaced by using seq_open_private()/seq_release_private(). Additionally, it documents the use of file->private_data to hold pointer to struct seq_file by seq_open(). This patch (of 3): Since patch described below, from v2.6.15-rc1, seq_open() could use a struct seq_file already allocated by the caller if the pointer to the structure is stored in file->private_data before calling the function. Commit 1abe77b0fc4b485927f1f798ae81a752677e1d05 Author: Al Viro <viro@zeniv.linux.org.uk> Date: Mon Nov 7 17:15:34 2005 -0500 [PATCH] allow callers of seq_open do allocation themselves Allow caller of seq_open() to kmalloc() seq_file + whatever else they want and set ->private_data to it. seq_open() will then abstain from doing allocation itself. Such behavior is only used by mounts_open_common(). In order to drop support for such uncommon feature, proc_mounts is converted to use seq_open_private(), which take care of allocating the proc_mounts structure, making it available through ->private in struct seq_file. Conversely, proc_mounts is converted to use seq_release_private(), in order to release the private structure allocated by seq_open_private(). Then, ->private is used directly instead of proc_mounts() macro to access to the proc_mounts structure. Link: http://lkml.kernel.org/r/cover.1433193673.git.ydroneaud@opteya.com Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/mount.h')
-rw-r--r--fs/mount.h3
1 files changed, 0 insertions, 3 deletions
diff --git a/fs/mount.h b/fs/mount.h
index b5b8082bfa42..14db05d424f7 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -118,7 +118,6 @@ static inline void unlock_mount_hash(void)
}
struct proc_mounts {
- struct seq_file m;
struct mnt_namespace *ns;
struct path root;
int (*show)(struct seq_file *, struct vfsmount *);
@@ -127,8 +126,6 @@ struct proc_mounts {
loff_t cached_index;
};
-#define proc_mounts(p) (container_of((p), struct proc_mounts, m))
-
extern const struct seq_operations mounts_op;
extern bool __is_local_mountpoint(struct dentry *dentry);