diff options
Diffstat (limited to 'fs/notify')
-rw-r--r-- | fs/notify/inode_mark.c | 42 | ||||
-rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 1 | ||||
-rw-r--r-- | fs/notify/inotify/inotify_user.c | 39 | ||||
-rw-r--r-- | fs/notify/mark.c | 1 | ||||
-rw-r--r-- | fs/notify/vfsmount_mark.c | 1 |
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> |