From 590e9d9861f5f21fbbb0266e40e6a17bc5084dd0 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Sun, 3 Sep 2017 00:04:31 +0800 Subject: [PATCH] ceph: fix "range cyclic" mode writepages In range cyclic mode, writepages() should first write dirty pages in range [writeback_index, (pgoff_t)-1], then write pages in range [0, writeback_index -1]. Besides, if writepages() encounters a page that beyond EOF, it should restart from the beginning. Signed-off-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov --- fs/ceph/addr.c | 41 ++++++++++++++++++++++++----------------- 1 file changed, 24 insertions(+), 17 deletions(-) diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 221df531b0c3..4a54f7369f51 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -781,16 +781,15 @@ static int ceph_writepages_start(struct address_space *mapping, struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_fs_client *fsc = ceph_inode_to_client(inode); struct ceph_vino vino = ceph_vino(inode); - pgoff_t index, start, end; - int range_whole = 0; - int should_loop = 1; + pgoff_t index, start_index, end; struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc; struct pagevec pvec; - int done = 0; int rc = 0; unsigned int wsize = i_blocksize(inode); struct ceph_osd_request *req = NULL; struct ceph_writeback_ctl ceph_wbc; + bool should_loop, range_whole = false; + bool stop, done = false; dout("writepages_start %p (mode=%s)\n", inode, wbc->sync_mode == WB_SYNC_NONE ? "NONE" : @@ -810,20 +809,22 @@ static int ceph_writepages_start(struct address_space *mapping, pagevec_init(&pvec, 0); + start_index = wbc->range_cyclic ? mapping->writeback_index : 0; + /* where to start/end? */ if (wbc->range_cyclic) { - start = mapping->writeback_index; /* Start from prev offset */ + index = start_index; end = -1; - dout(" cyclic, start at %lu\n", start); + should_loop = (index > 0); + dout(" cyclic, start at %lu\n", index); } else { - start = wbc->range_start >> PAGE_SHIFT; + index = wbc->range_start >> PAGE_SHIFT; end = wbc->range_end >> PAGE_SHIFT; if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) - range_whole = 1; - should_loop = 0; - dout(" not cyclic, %lu to %lu\n", start, end); + range_whole = true; + should_loop = false; + dout(" not cyclic, %lu to %lu\n", index, end); } - index = start; retry: /* find oldest snap context with dirty data */ @@ -847,7 +848,8 @@ retry: } last_snapc = snapc; - while (!done && index <= end) { + stop = false; + while (!stop && index <= end) { int num_ops = 0, op_idx; unsigned i, pvec_pages, max_pages, locked_pages = 0; struct page **pages = NULL, **data_pages; @@ -885,9 +887,11 @@ get_more_pages: unlock_page(page); continue; } - if (!wbc->range_cyclic && page->index > end) { + if (page->index > end) { dout("end of range %p\n", page); - done = 1; + /* can't be range_cyclic (1st pass) because + * end == -1 in that case. */ + stop = done = true; unlock_page(page); break; } @@ -899,7 +903,8 @@ get_more_pages: if (page_offset(page) >= ceph_wbc.i_size) { dout("%p page eof %llu\n", page, ceph_wbc.i_size); - done = 1; + /* not done if range_cyclic */ + stop = true; unlock_page(page); break; } @@ -1132,7 +1137,7 @@ new_request: goto new_request; if (wbc->nr_to_write <= 0) - done = 1; + stop = done = true; release_pvec_pages: dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, @@ -1146,7 +1151,9 @@ release_pvec_pages: if (should_loop && !done) { /* more to do; loop back to beginning of file */ dout("writepages looping back to beginning of file\n"); - should_loop = 0; + should_loop = false; + end = start_index - 1; + index = 0; goto retry; } -- 2.20.1