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authorPablo Neira Ayuso <pablo@netfilter.org>2016-09-25 23:23:57 +0200
committerPablo Neira Ayuso <pablo@netfilter.org>2016-09-25 23:34:19 +0200
commitf20fbc0717f9f007c94b2641134b19228d0ce9ed (patch)
tree1404248ebbec552a3fb7928b75322b65d74de1bd /fs/autofs4/expire.c
parentnetfilter: nf_log: get rid of XT_LOG_* macros (diff)
parentMerge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirshe... (diff)
downloadlinux-f20fbc0717f9f007c94b2641134b19228d0ce9ed.tar.gz
linux-f20fbc0717f9f007c94b2641134b19228d0ce9ed.zip
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Conflicts: net/netfilter/core.c net/netfilter/nf_tables_netdev.c Resolve two conflicts before pull request for David's net-next tree: 1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant ip_hdr assignment") from the net tree and commit ddc8b6027ad0 ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()"). 2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and Aaron Conole's patches to replace list_head with single linked list. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'fs/autofs4/expire.c')
-rw-r--r--fs/autofs4/expire.c55
1 files changed, 42 insertions, 13 deletions
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index b493909e7492..d8e6d421c27f 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -417,6 +417,7 @@ static struct dentry *should_expire(struct dentry *dentry,
}
return NULL;
}
+
/*
* Find an eligible tree to time-out
* A tree is eligible if :-
@@ -432,6 +433,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
struct dentry *root = sb->s_root;
struct dentry *dentry;
struct dentry *expired;
+ struct dentry *found;
struct autofs_info *ino;
if (!root)
@@ -442,31 +444,46 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
dentry = NULL;
while ((dentry = get_next_positive_subdir(dentry, root))) {
+ int flags = how;
+
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
- if (ino->flags & AUTOFS_INF_WANT_EXPIRE)
- expired = NULL;
- else
- expired = should_expire(dentry, mnt, timeout, how);
- if (!expired) {
+ if (ino->flags & AUTOFS_INF_WANT_EXPIRE) {
spin_unlock(&sbi->fs_lock);
continue;
}
+ spin_unlock(&sbi->fs_lock);
+
+ expired = should_expire(dentry, mnt, timeout, flags);
+ if (!expired)
+ continue;
+
+ spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(expired);
ino->flags |= AUTOFS_INF_WANT_EXPIRE;
spin_unlock(&sbi->fs_lock);
synchronize_rcu();
- spin_lock(&sbi->fs_lock);
- if (should_expire(expired, mnt, timeout, how)) {
- if (expired != dentry)
- dput(dentry);
- goto found;
- }
+ /* Make sure a reference is not taken on found if
+ * things have changed.
+ */
+ flags &= ~AUTOFS_EXP_LEAVES;
+ found = should_expire(expired, mnt, timeout, how);
+ if (!found || found != expired)
+ /* Something has changed, continue */
+ goto next;
+
+ if (expired != dentry)
+ dput(dentry);
+
+ spin_lock(&sbi->fs_lock);
+ goto found;
+next:
+ spin_lock(&sbi->fs_lock);
ino->flags &= ~AUTOFS_INF_WANT_EXPIRE;
+ spin_unlock(&sbi->fs_lock);
if (expired != dentry)
dput(expired);
- spin_unlock(&sbi->fs_lock);
}
return NULL;
@@ -483,6 +500,7 @@ int autofs4_expire_wait(struct dentry *dentry, int rcu_walk)
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
int status;
+ int state;
/* Block on any pending expire */
if (!(ino->flags & AUTOFS_INF_WANT_EXPIRE))
@@ -490,8 +508,19 @@ int autofs4_expire_wait(struct dentry *dentry, int rcu_walk)
if (rcu_walk)
return -ECHILD;
+retry:
spin_lock(&sbi->fs_lock);
- if (ino->flags & AUTOFS_INF_EXPIRING) {
+ state = ino->flags & (AUTOFS_INF_WANT_EXPIRE | AUTOFS_INF_EXPIRING);
+ if (state == AUTOFS_INF_WANT_EXPIRE) {
+ spin_unlock(&sbi->fs_lock);
+ /*
+ * Possibly being selected for expire, wait until
+ * it's selected or not.
+ */
+ schedule_timeout_uninterruptible(HZ/10);
+ goto retry;
+ }
+ if (state & AUTOFS_INF_EXPIRING) {
spin_unlock(&sbi->fs_lock);
pr_debug("waiting for expire %p name=%pd\n", dentry, dentry);