From a2e1d4f2e5ed83850de92a491ef225824cb457bd Mon Sep 17 00:00:00 2001 From: Fred Isaman Date: Mon, 13 Jun 2011 18:54:53 -0400 Subject: nfs4.1: fix several problems with _pnfs_return_layout _pnfs_return_layout had the following problems: - it did not call pnfs_free_lseg_list on all paths - it unintentionally did a forgetful return when there was no outstanding io - it raced with concurrent LAYOUTGETS Signed-off-by: Fred Isaman Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 8c1309d852a..25de6b27bdf 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -634,12 +634,14 @@ _pnfs_return_layout(struct inode *ino) spin_lock(&ino->i_lock); lo = nfsi->layout; - if (!lo || !mark_matching_lsegs_invalid(lo, &tmp_list, NULL)) { + if (!lo) { spin_unlock(&ino->i_lock); - dprintk("%s: no layout segments to return\n", __func__); - goto out; + dprintk("%s: no layout to return\n", __func__); + return status; } stateid = nfsi->layout->plh_stateid; + mark_matching_lsegs_invalid(lo, &tmp_list, NULL); + lo->plh_block_lgets++; /* Reference matched in nfs4_layoutreturn_release */ get_layout_hdr(lo); spin_unlock(&ino->i_lock); -- cgit v1.2.3-18-g5258 From d771e3a43e23a37398b7e05a9d1b1036d698263c Mon Sep 17 00:00:00 2001 From: Benny Halevy Date: Tue, 14 Jun 2011 16:30:16 -0400 Subject: NFSv4.1: fix break condition in pnfs_find_lseg The break condition to skip out of the loop got broken when cmp_layout was change. Essentially, we want to stop looking once we know no layout on the remainder of the list can match the first byte of the looked-up range. Reported-by: Peng Tao Signed-off-by: Benny Halevy Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 25de6b27bdf..d066aad608a 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -889,7 +889,7 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, ret = get_lseg(lseg); break; } - if (cmp_layout(range, &lseg->pls_range) > 0) + if (lseg->pls_range.offset > range->offset) break; } -- cgit v1.2.3-18-g5258 From 1ed3a8539af7b36aa5c977f304e80f7fc8d27bfc Mon Sep 17 00:00:00 2001 From: Benny Halevy Date: Wed, 15 Jun 2011 11:39:57 -0400 Subject: NFSv4.1: need to put_layout_hdr on _pnfs_return_layout error path We always get a reference on the layout header and we rely on nfs4_layoutreturn_release to put it. If we hit an allocation error before starting the rpc proc we bail out early without dereferncing the layout header properly. Signed-off-by: Benny Halevy Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index d066aad608a..8f958228125 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -652,6 +652,7 @@ _pnfs_return_layout(struct inode *ino) lrp = kzalloc(sizeof(*lrp), GFP_KERNEL); if (unlikely(lrp == NULL)) { status = -ENOMEM; + put_layout_hdr(lo); goto out; } -- cgit v1.2.3-18-g5258 From ea0ded748bdea78f9e2fefb571f7d6ce9edb4f89 Mon Sep 17 00:00:00 2001 From: Fred Isaman Date: Wed, 15 Jun 2011 12:31:02 -0400 Subject: nfs4.1: prevent race that allowed use of freed layout in _pnfs_return_layout mark_matching_lsegs_invalid could put the last ref to the layout, so the get_layout_hdr needs to be called first. Signed-off-by: Fred Isaman Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 8f958228125..730d4dbbaf6 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -640,10 +640,10 @@ _pnfs_return_layout(struct inode *ino) return status; } stateid = nfsi->layout->plh_stateid; - mark_matching_lsegs_invalid(lo, &tmp_list, NULL); - lo->plh_block_lgets++; /* Reference matched in nfs4_layoutreturn_release */ get_layout_hdr(lo); + mark_matching_lsegs_invalid(lo, &tmp_list, NULL); + lo->plh_block_lgets++; spin_unlock(&ino->i_lock); pnfs_free_lseg_list(&tmp_list); -- cgit v1.2.3-18-g5258 From 9e2dfdb3081edfae66a49013517e80dd8a0469fa Mon Sep 17 00:00:00 2001 From: Fred Isaman Date: Wed, 15 Jun 2011 14:32:02 -0400 Subject: nfs4.1: mark layout as bad on error path in _pnfs_return_layout Signed-off-by: Fred Isaman Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 730d4dbbaf6..539b94cb6c0 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -652,6 +652,8 @@ _pnfs_return_layout(struct inode *ino) lrp = kzalloc(sizeof(*lrp), GFP_KERNEL); if (unlikely(lrp == NULL)) { status = -ENOMEM; + set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags); + set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags); put_layout_hdr(lo); goto out; } -- cgit v1.2.3-18-g5258 From 8f7d5efbef8718a774ac5e347b4ec069f17fd9b4 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 10 Jun 2011 13:30:22 -0400 Subject: NFSv4.1: Fix some issues with pnfs_generic_pg_test 1. If the intention is to coalesce requests 'prev' and 'req' then we have to ensure at least that we have a layout starting at req_offset(prev). 2. If we're only requesting a minimal layout of length desc->pg_count, we need to test the length actually returned by the server before we allow the coalescing to occur. 3. We need to deal correctly with (pgio->lseg == NULL) 4. Fixup the test guarding the pnfs_update_layout. Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 539b94cb6c0..0f42e02436e 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1064,19 +1064,21 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, gfp_flags = GFP_NOFS; } - if (pgio->pg_count == prev->wb_bytes) { + if (pgio->pg_lseg == NULL) { + if (pgio->pg_count != prev->wb_bytes) + return true; /* This is first coelesce call for a series of nfs_pages */ pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode, prev->wb_context, - req_offset(req), + req_offset(prev), pgio->pg_count, access_type, gfp_flags); - return true; + if (pgio->pg_lseg == NULL) + return true; } - if (pgio->pg_lseg && - req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset, + if (req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset, pgio->pg_lseg->pls_range.length)) return false; -- cgit v1.2.3-18-g5258 From 19982ba8562e33083cb5bbb59a74855d8a9624ea Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 10 Jun 2011 13:30:23 -0400 Subject: NFSv4.1: Fix an off-by-one error in pnfs_generic_pg_test And document what is going on there... Signed-off-by: Trond Myklebust --- fs/nfs/pnfs.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'fs/nfs/pnfs.c') diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 0f42e02436e..29c0ca7fc34 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1078,11 +1078,22 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, return true; } - if (req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset, - pgio->pg_lseg->pls_range.length)) - return false; - - return true; + /* + * Test if a nfs_page is fully contained in the pnfs_layout_range. + * Note that this test makes several assumptions: + * - that the previous nfs_page in the struct nfs_pageio_descriptor + * is known to lie within the range. + * - that the nfs_page being tested is known to be contiguous with the + * previous nfs_page. + * - Layout ranges are page aligned, so we only have to test the + * start offset of the request. + * + * Please also note that 'end_offset' is actually the offset of the + * first byte that lies outside the pnfs_layout_range. FIXME? + * + */ + return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset, + pgio->pg_lseg->pls_range.length); } EXPORT_SYMBOL_GPL(pnfs_generic_pg_test); -- cgit v1.2.3-18-g5258