ceph: don't use truncate_pagecache() to invalidate read cache

truncate_pagecache() drops dirty pages, it's dangerous to use it
to invalidate read cache. Besides, we shouldn't start invalidating
read cache while there are buffer writers. Because buffer writers
may add dirty pages later.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index fab93c6..c17b5d7 100644 (file)
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1656,7 +1656,7 @@ retry_locked:
         */
        if ((!is_delayed || mdsc->stopping) &&
            !S_ISDIR(inode->i_mode) &&          /* ignore readdir cache */
-           ci->i_wrbuffer_ref == 0 &&          /* no dirty pages... */
+           !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
            inode->i_data.nrpages &&            /* have cached pages */
            (revoking & (CEPH_CAP_FILE_CACHE|
                         CEPH_CAP_FILE_LAZYIO)) && /*  or revoking cache */
@@ -1698,8 +1698,8 @@ retry_locked:
 
                revoking = cap->implemented & ~cap->issued;
                dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
-                    cap->mds, cap, ceph_cap_string(cap->issued),
-                    ceph_cap_string(cap_used),
+                    cap->mds, cap, ceph_cap_string(cap_used),
+                    ceph_cap_string(cap->issued),
                     ceph_cap_string(cap->implemented),
                     ceph_cap_string(revoking));
 
@@ -2828,7 +2828,7 @@ static void handle_cap_grant(struct ceph_mds_client *mdsc,
        if (!S_ISDIR(inode->i_mode) && /* don't invalidate readdir cache */
            ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
            (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
-           !ci->i_wrbuffer_ref) {
+           !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
                if (try_nonblocking_invalidate(inode)) {
                        /* there were locked pages.. invalidate later
                           in a separate thread. */

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 89d0815..07495ba 100644 (file)
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1728,7 +1728,9 @@ static void ceph_invalidate_work(struct work_struct *work)
        orig_gen = ci->i_rdcache_gen;
        spin_unlock(&ci->i_ceph_lock);
 
-       truncate_pagecache(inode, 0);
+       if (invalidate_inode_pages2(inode->i_mapping) < 0) {
+               pr_err("invalidate_pages %p fails\n", inode);
+       }
 
        spin_lock(&ci->i_ceph_lock);
        if (orig_gen == ci->i_rdcache_gen &&