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-rw-r--r--fs/notify/inode_mark.c42
-rw-r--r--fs/notify/inotify/inotify_fsnotify.c1
-rw-r--r--fs/notify/inotify/inotify_user.c39
-rw-r--r--fs/notify/mark.c1
-rw-r--r--fs/notify/vfsmount_mark.c1
5 files changed, 39 insertions, 45 deletions
diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c
index 4c29fcf557d..07ea8d3e6ea 100644
--- a/fs/notify/inode_mark.c
+++ b/fs/notify/inode_mark.c
@@ -22,13 +22,14 @@
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
-#include <linux/writeback.h> /* for inode_lock */
#include <asm/atomic.h>
#include <linux/fsnotify_backend.h>
#include "fsnotify.h"
+#include "../internal.h"
+
/*
* Recalculate the mask of events relevant to a given inode locked.
*/
@@ -237,15 +238,14 @@ out:
* fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes.
* @list: list of inodes being unmounted (sb->s_inodes)
*
- * Called with inode_lock held, protecting the unmounting super block's list
- * of inodes, and with iprune_mutex held, keeping shrink_icache_memory() at bay.
- * We temporarily drop inode_lock, however, and CAN block.
+ * Called during unmount with no locks held, so needs to be safe against
+ * concurrent modifiers. We temporarily drop inode_sb_list_lock and CAN block.
*/
void fsnotify_unmount_inodes(struct list_head *list)
{
struct inode *inode, *next_i, *need_iput = NULL;
- spin_lock(&inode_lock);
+ spin_lock(&inode_sb_list_lock);
list_for_each_entry_safe(inode, next_i, list, i_sb_list) {
struct inode *need_iput_tmp;
@@ -254,8 +254,11 @@ void fsnotify_unmount_inodes(struct list_head *list)
* I_WILL_FREE, or I_NEW which is fine because by that point
* the inode cannot have any associated watches.
*/
- if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW))
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) {
+ spin_unlock(&inode->i_lock);
continue;
+ }
/*
* If i_count is zero, the inode cannot have any watches and
@@ -263,8 +266,10 @@ void fsnotify_unmount_inodes(struct list_head *list)
* evict all inodes with zero i_count from icache which is
* unnecessarily violent and may in fact be illegal to do.
*/
- if (!atomic_read(&inode->i_count))
+ if (!atomic_read(&inode->i_count)) {
+ spin_unlock(&inode->i_lock);
continue;
+ }
need_iput_tmp = need_iput;
need_iput = NULL;
@@ -274,22 +279,25 @@ void fsnotify_unmount_inodes(struct list_head *list)
__iget(inode);
else
need_iput_tmp = NULL;
+ spin_unlock(&inode->i_lock);
/* In case the dropping of a reference would nuke next_i. */
if ((&next_i->i_sb_list != list) &&
- atomic_read(&next_i->i_count) &&
- !(next_i->i_state & (I_FREEING | I_WILL_FREE))) {
- __iget(next_i);
- need_iput = next_i;
+ atomic_read(&next_i->i_count)) {
+ spin_lock(&next_i->i_lock);
+ if (!(next_i->i_state & (I_FREEING | I_WILL_FREE))) {
+ __iget(next_i);
+ need_iput = next_i;
+ }
+ spin_unlock(&next_i->i_lock);
}
/*
- * We can safely drop inode_lock here because we hold
+ * We can safely drop inode_sb_list_lock here because we hold
* references on both inode and next_i. Also no new inodes
- * will be added since the umount has begun. Finally,
- * iprune_mutex keeps shrink_icache_memory() away.
+ * will be added since the umount has begun.
*/
- spin_unlock(&inode_lock);
+ spin_unlock(&inode_sb_list_lock);
if (need_iput_tmp)
iput(need_iput_tmp);
@@ -301,7 +309,7 @@ void fsnotify_unmount_inodes(struct list_head *list)
iput(inode);
- spin_lock(&inode_lock);
+ spin_lock(&inode_sb_list_lock);
}
- spin_unlock(&inode_lock);
+ spin_unlock(&inode_sb_list_lock);
}
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index a91b69a6a29..0348d0c8f65 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -198,6 +198,7 @@ static void inotify_free_group_priv(struct fsnotify_group *group)
idr_for_each(&group->inotify_data.idr, idr_callback, group);
idr_remove_all(&group->inotify_data.idr);
idr_destroy(&group->inotify_data.idr);
+ atomic_dec(&group->inotify_data.user->inotify_devs);
free_uid(group->inotify_data.user);
}
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index bd46e7c8a0e..8445fbc8985 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -290,7 +290,6 @@ static int inotify_fasync(int fd, struct file *file, int on)
static int inotify_release(struct inode *ignored, struct file *file)
{
struct fsnotify_group *group = file->private_data;
- struct user_struct *user = group->inotify_data.user;
pr_debug("%s: group=%p\n", __func__, group);
@@ -299,8 +298,6 @@ static int inotify_release(struct inode *ignored, struct file *file)
/* free this group, matching get was inotify_init->fsnotify_obtain_group */
fsnotify_put_group(group);
- atomic_dec(&user->inotify_devs);
-
return 0;
}
@@ -697,7 +694,7 @@ retry:
return ret;
}
-static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsigned int max_events)
+static struct fsnotify_group *inotify_new_group(unsigned int max_events)
{
struct fsnotify_group *group;
@@ -710,8 +707,14 @@ static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsign
spin_lock_init(&group->inotify_data.idr_lock);
idr_init(&group->inotify_data.idr);
group->inotify_data.last_wd = 0;
- group->inotify_data.user = user;
group->inotify_data.fa = NULL;
+ group->inotify_data.user = get_current_user();
+
+ if (atomic_inc_return(&group->inotify_data.user->inotify_devs) >
+ inotify_max_user_instances) {
+ fsnotify_put_group(group);
+ return ERR_PTR(-EMFILE);
+ }
return group;
}
@@ -721,7 +724,6 @@ static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsign
SYSCALL_DEFINE1(inotify_init1, int, flags)
{
struct fsnotify_group *group;
- struct user_struct *user;
int ret;
/* Check the IN_* constants for consistency. */
@@ -731,31 +733,16 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
if (flags & ~(IN_CLOEXEC | IN_NONBLOCK))
return -EINVAL;
- user = get_current_user();
- if (unlikely(atomic_read(&user->inotify_devs) >=
- inotify_max_user_instances)) {
- ret = -EMFILE;
- goto out_free_uid;
- }
-
/* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */
- group = inotify_new_group(user, inotify_max_queued_events);
- if (IS_ERR(group)) {
- ret = PTR_ERR(group);
- goto out_free_uid;
- }
-
- atomic_inc(&user->inotify_devs);
+ group = inotify_new_group(inotify_max_queued_events);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
ret = anon_inode_getfd("inotify", &inotify_fops, group,
O_RDONLY | flags);
- if (ret >= 0)
- return ret;
+ if (ret < 0)
+ fsnotify_put_group(group);
- fsnotify_put_group(group);
- atomic_dec(&user->inotify_devs);
-out_free_uid:
- free_uid(user);
return ret;
}
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index 325185e514b..50c00856f73 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -91,7 +91,6 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/srcu.h>
-#include <linux/writeback.h> /* for inode_lock */
#include <asm/atomic.h>
diff --git a/fs/notify/vfsmount_mark.c b/fs/notify/vfsmount_mark.c
index 85eebff6d0d..e86577d6c5c 100644
--- a/fs/notify/vfsmount_mark.c
+++ b/fs/notify/vfsmount_mark.c
@@ -23,7 +23,6 @@
#include <linux/mount.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
-#include <linux/writeback.h> /* for inode_lock */
#include <asm/atomic.h>