ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)
we should not do block operation in wait_event_interruptible()'s condition
check function, but reading inline data can block. so move the read inline
data code to ceph_get_caps()
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 844b57c..8172775 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2072,17 +2072,16 @@
* requested from the MDS.
*/
static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
- loff_t endoff, int *got, struct page **pinned_page,
- int *check_max, int *err)
+ loff_t endoff, int *got, int *check_max, int *err)
{
struct inode *inode = &ci->vfs_inode;
int ret = 0;
- int have, implemented, _got = 0;
+ int have, implemented;
int file_wanted;
dout("get_cap_refs %p need %s want %s\n", inode,
ceph_cap_string(need), ceph_cap_string(want));
-again:
+
spin_lock(&ci->i_ceph_lock);
/* make sure file is actually open */
@@ -2137,8 +2136,8 @@
inode, ceph_cap_string(have), ceph_cap_string(not),
ceph_cap_string(revoking));
if ((revoking & not) == 0) {
- _got = need | (have & want);
- __take_cap_refs(ci, _got);
+ *got = need | (have & want);
+ __take_cap_refs(ci, *got);
ret = 1;
}
} else {
@@ -2163,39 +2162,8 @@
out_unlock:
spin_unlock(&ci->i_ceph_lock);
- if (ci->i_inline_version != CEPH_INLINE_NONE &&
- (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
- i_size_read(inode) > 0) {
- int ret1;
- struct page *page = find_get_page(inode->i_mapping, 0);
- if (page) {
- if (PageUptodate(page)) {
- *pinned_page = page;
- goto out;
- }
- page_cache_release(page);
- }
- /*
- * drop cap refs first because getattr while holding
- * caps refs can cause deadlock.
- */
- ceph_put_cap_refs(ci, _got);
- _got = 0;
-
- /* getattr request will bring inline data into page cache */
- ret1 = __ceph_do_getattr(inode, NULL,
- CEPH_STAT_CAP_INLINE_DATA, true);
- if (ret1 >= 0) {
- ret = 0;
- goto again;
- }
- *err = ret1;
- ret = 1;
- }
-out:
dout("get_cap_refs %p ret %d got %s\n", inode,
- ret, ceph_cap_string(_got));
- *got = _got;
+ ret, ceph_cap_string(*got));
return ret;
}
@@ -2235,22 +2203,52 @@
int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
loff_t endoff, int *got, struct page **pinned_page)
{
- int check_max, ret, err;
+ int _got, check_max, ret, err = 0;
retry:
if (endoff > 0)
check_max_size(&ci->vfs_inode, endoff);
+ _got = 0;
check_max = 0;
- err = 0;
ret = wait_event_interruptible(ci->i_cap_wq,
- try_get_cap_refs(ci, need, want, endoff,
- got, pinned_page,
- &check_max, &err));
+ try_get_cap_refs(ci, need, want, endoff,
+ &_got, &check_max, &err));
if (err)
ret = err;
+ if (ret < 0)
+ return ret;
+
if (check_max)
goto retry;
- return ret;
+
+ if (ci->i_inline_version != CEPH_INLINE_NONE &&
+ (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
+ i_size_read(&ci->vfs_inode) > 0) {
+ struct page *page = find_get_page(ci->vfs_inode.i_mapping, 0);
+ if (page) {
+ if (PageUptodate(page)) {
+ *pinned_page = page;
+ goto out;
+ }
+ page_cache_release(page);
+ }
+ /*
+ * drop cap refs first because getattr while holding
+ * caps refs can cause deadlock.
+ */
+ ceph_put_cap_refs(ci, _got);
+ _got = 0;
+
+ /* getattr request will bring inline data into page cache */
+ ret = __ceph_do_getattr(&ci->vfs_inode, NULL,
+ CEPH_STAT_CAP_INLINE_DATA, true);
+ if (ret < 0)
+ return ret;
+ goto retry;
+ }
+out:
+ *got = _got;
+ return 0;
}
/*