diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 4958a2ef3e0482a7e338630973c74b42a7a385c4..e1e6df0f549e63d315e9a39d8acd6da8839750ba 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -1361,6 +1361,41 @@ static int __mark_caps_flushing(struct inode *inode, return flushing; } +/* + * try to invalidate mapping pages without blocking. + */ +static int mapping_is_empty(struct address_space *mapping) +{ + struct page *page = find_get_page(mapping, 0); + + if (!page) + return 1; + + put_page(page); + return 0; +} + +static int try_nonblocking_invalidate(struct inode *inode) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + u32 invalidating_gen = ci->i_rdcache_gen; + + spin_unlock(&inode->i_lock); + invalidate_mapping_pages(&inode->i_data, 0, -1); + spin_lock(&inode->i_lock); + + if (mapping_is_empty(&inode->i_data) && + invalidating_gen == ci->i_rdcache_gen) { + /* success. */ + dout("try_nonblocking_invalidate %p success\n", inode); + ci->i_rdcache_gen = 0; + ci->i_rdcache_revoking = 0; + return 0; + } + dout("try_nonblocking_invalidate %p failed\n", inode); + return -1; +} + /* * Swiss army knife function to examine currently used and wanted * versus held caps. Release, flush, ack revoked caps to mds as @@ -1451,27 +1486,19 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags, (file_wanted == 0 || /* no open files */ (revoking & CEPH_CAP_FILE_CACHE)) && /* or revoking cache */ !tried_invalidate) { - u32 invalidating_gen = ci->i_rdcache_gen; - int ret; - dout("check_caps trying to invalidate on %p\n", inode); - spin_unlock(&inode->i_lock); - ret = invalidate_mapping_pages(&inode->i_data, 0, -1); - spin_lock(&inode->i_lock); - if (ret == 0 && invalidating_gen == ci->i_rdcache_gen) { - /* success. */ - ci->i_rdcache_gen = 0; - ci->i_rdcache_revoking = 0; - } else if (revoking & CEPH_CAP_FILE_CACHE) { - dout("check_caps queuing invalidate\n"); - queue_invalidate = 1; - ci->i_rdcache_revoking = ci->i_rdcache_gen; - } else { - dout("check_caps failed to invalidate pages\n"); - /* we failed to invalidate pages. check these - caps again later. */ - force_requeue = 1; - __cap_set_timeouts(mdsc, ci); + if (try_nonblocking_invalidate(inode) < 0) { + if (revoking & CEPH_CAP_FILE_CACHE) { + dout("check_caps queuing invalidate\n"); + queue_invalidate = 1; + ci->i_rdcache_revoking = ci->i_rdcache_gen; + } else { + dout("check_caps failed to invalidate pages\n"); + /* we failed to invalidate pages. check these + caps again later. */ + force_requeue = 1; + __cap_set_timeouts(mdsc, ci); + } } tried_invalidate = 1; goto retry_locked; @@ -2184,7 +2211,6 @@ static int handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant, int revoked_rdcache = 0; int queue_invalidate = 0; int tried_invalidate = 0; - int ret; dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n", inode, cap, mds, seq, ceph_cap_string(newcaps)); @@ -2199,24 +2225,16 @@ static int handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant, restart: if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) && !ci->i_wrbuffer_ref && !tried_invalidate) { - dout("CACHE invalidation\n"); - spin_unlock(&inode->i_lock); tried_invalidate = 1; - - ret = invalidate_mapping_pages(&inode->i_data, 0, -1); - spin_lock(&inode->i_lock); - if (ret < 0) { + if (try_nonblocking_invalidate(inode) == 0) { + revoked_rdcache = 1; + } else { /* there were locked pages.. invalidate later in a separate thread. */ if (ci->i_rdcache_revoking != ci->i_rdcache_gen) { queue_invalidate = 1; ci->i_rdcache_revoking = ci->i_rdcache_gen; } - } else { - /* we successfully invalidated those pages */ - revoked_rdcache = 1; - ci->i_rdcache_gen = 0; - ci->i_rdcache_revoking = 0; } goto restart; }