Avoid i_shared_gen overflow and allow accessing i_shared_gen without
holding i_ceph_lock (prepare for later patch)
Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx>
---
fs/ceph/caps.c | 2 +-
fs/ceph/dir.c | 16 ++++++++--------
fs/ceph/inode.c | 4 ++--
fs/ceph/super.h | 5 +++--
4 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 029cab713731..2b3c8b1c774c 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -498,7 +498,7 @@ static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
*/
if ((issued & CEPH_CAP_FILE_SHARED) != (had & CEPH_CAP_FILE_SHARED)) {
if (issued & CEPH_CAP_FILE_SHARED)
- ci->i_shared_gen++;
+ atomic64_inc(&ci->i_shared_gen);
if (S_ISDIR(ci->vfs_inode.i_mode)) {
dout(" marking %p NOT complete\n", &ci->vfs_inode);
__ceph_dir_clear_complete(ci);
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 64afa46b211f..0a23a4d9fde8 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -173,7 +173,7 @@ __dcache_find_get_entry(struct dentry *parent, u64 idx,
* the MDS if/when the directory is modified).
*/
static int __dcache_readdir(struct file *file, struct dir_context *ctx,
- u32 shared_gen)
+ long long shared_gen)
{
struct ceph_file_info *fi = file->private_data;
struct dentry *parent = file->f_path.dentry;
@@ -184,7 +184,7 @@ static int __dcache_readdir(struct file *file, struct dir_context *ctx,
u64 idx = 0;
int err = 0;
- dout("__dcache_readdir %p v%u at %llx\n", dir, shared_gen, ctx->pos);
+ dout("__dcache_readdir %p v%llu at %llx\n", dir, (u64)shared_gen, ctx->pos);
/* search start position */
if (ctx->pos > 2) {
@@ -333,7 +333,7 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
ceph_snap(inode) != CEPH_SNAPDIR &&
__ceph_dir_is_complete_ordered(ci) &&
__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
- u32 shared_gen = ci->i_shared_gen;
+ long long shared_gen = atomic64_read(&ci->i_shared_gen);
spin_unlock(&ci->i_ceph_lock);
err = __dcache_readdir(file, ctx, shared_gen);
if (err != -EAGAIN)
@@ -751,7 +751,7 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
spin_unlock(&ci->i_ceph_lock);
dout(" dir %p complete, -ENOENT\n", dir);
d_add(dentry, NULL);
- di->lease_shared_gen = ci->i_shared_gen;
+ di->lease_shared_gen = atomic64_read(&ci->i_shared_gen);
return NULL;
}
spin_unlock(&ci->i_ceph_lock);
@@ -1191,12 +1191,12 @@ static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
int valid = 0;
spin_lock(&ci->i_ceph_lock);
- if (ci->i_shared_gen == di->lease_shared_gen)
+ if (atomic64_read(&ci->i_shared_gen) == di->lease_shared_gen)
valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
spin_unlock(&ci->i_ceph_lock);
- dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
- dir, (unsigned)ci->i_shared_gen, dentry,
- (unsigned)di->lease_shared_gen, valid);
+ dout("dir_lease_is_valid dir %p v%llu dentry %p v%llu = %d\n",
+ dir, (u64)atomic64_read(&ci->i_shared_gen),
+ dentry, (u64)di->lease_shared_gen, valid);
return valid;
}
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 666ad10e2b85..a9de83f012bf 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -494,7 +494,7 @@ struct inode *ceph_alloc_inode(struct super_block *sb)
ci->i_wrbuffer_ref = 0;
ci->i_wrbuffer_ref_head = 0;
atomic_set(&ci->i_filelock_ref, 0);
- ci->i_shared_gen = 0;
+ atomic64_set(&ci->i_shared_gen, 0);
ci->i_rdcache_gen = 0;
ci->i_rdcache_revoking = 0;
@@ -1041,7 +1041,7 @@ static void update_dentry_lease(struct dentry *dentry,
if (ceph_snap(dir) != CEPH_NOSNAP)
goto out_unlock;
- di->lease_shared_gen = ceph_inode(dir)->i_shared_gen;
+ di->lease_shared_gen = atomic64_read(&ceph_inode(dir)->i_shared_gen);
if (duration == 0)
goto out_unlock;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 2beeec07fa76..ec301fce2556 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -256,7 +256,8 @@ struct ceph_inode_xattr {
*/
struct ceph_dentry_info {
struct ceph_mds_session *lease_session;
- u32 lease_gen, lease_shared_gen;
+ long long lease_shared_gen;
+ u32 lease_gen;
u32 lease_seq;
unsigned long lease_renew_after, lease_renew_from;
struct list_head lru;
@@ -353,7 +354,7 @@ struct ceph_inode_info {
int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
int i_wrbuffer_ref, i_wrbuffer_ref_head;
atomic_t i_filelock_ref;
- u32 i_shared_gen; /* increment each time we get FILE_SHARED */
+ atomic64_t i_shared_gen; /* increment each time we get FILE_SHARED */
u32 i_rdcache_gen; /* incremented each time we get FILE_CACHE. */
u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
--
2.13.6
--
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