summaryrefslogtreecommitdiff
path: root/fs/nfs/read.c
AgeCommit message (Collapse)AuthorFilesLines
2015-09-20NFS: Do cleanup before resetting pageio read/write to mdsKinglong Mee1-0/+3
There is a reference leak of layout segment after resetting pageio read/write to mds. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-27Merge tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-1/+1
Pull NFS client updates from Trond Myklebust: "Another set of mainly bugfixes and a couple of cleanups. No new functionality in this round. Highlights include: Stable patches: - Fix a regression in /proc/self/mountstats - Fix the pNFS flexfiles O_DIRECT support - Fix high load average due to callback thread sleeping Bugfixes: - Various patches to fix the pNFS layoutcommit support - Do not cache pNFS deviceids unless server notifications are enabled - Fix a SUNRPC transport reconnection regression - make debugfs file creation failure non-fatal in SUNRPC - Another fix for circular directory warnings on NFSv4 "junctioned" mountpoints - Fix locking around NFSv4.2 fallocate() support - Truncating NFSv4 file opens should also sync O_DIRECT writes - Prevent infinite loop in rpcrdma_ep_create() Features: - Various improvements to the RDMA transport code's handling of memory registration - Various code cleanups" * tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (55 commits) fs/nfs: fix new compiler warning about boolean in switch nfs: Remove unneeded casts in nfs NFS: Don't attempt to decode missing directory entries Revert "nfs: replace nfs_add_stats with nfs_inc_stats when add one" NFS: Rename idmap.c to nfs4idmap.c NFS: Move nfs_idmap.h into fs/nfs/ NFS: Remove CONFIG_NFS_V4 checks from nfs_idmap.h NFS: Add a stub for GETDEVICELIST nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes nfs: fix DIO good bytes calculation nfs: Fetch MOUNTED_ON_FILEID when updating an inode sunrpc: make debugfs file creation failure non-fatal nfs: fix high load average due to callback thread sleeping NFS: Reduce time spent holding the i_mutex during fallocate() NFS: Don't zap caches on fallocate() xprtrdma: Make rpcrdma_{un}map_one() into inline functions xprtrdma: Handle non-SEND completions via a callout xprtrdma: Add "open" memreg op xprtrdma: Add "destroy MRs" memreg op xprtrdma: Add "reset MRs" memreg op ...
2015-04-23Revert "nfs: replace nfs_add_stats with nfs_inc_stats when add one"Nicolas Iooss1-1/+1
This reverts commit 5a254d08b086d80cbead2ebcee6d2a4b3a15587a. Since commit 5a254d08b086 ("nfs: replace nfs_add_stats with nfs_inc_stats when add one"), nfs_readpage and nfs_do_writepage use nfs_inc_stats to increment NFSIOS_READPAGES and NFSIOS_WRITEPAGES instead of nfs_add_stats. However nfs_inc_stats does not do the same thing as nfs_add_stats with value 1 because these functions work on distinct stats: nfs_inc_stats increments stats from "enum nfs_stat_eventcounters" (in server->io_stats->events) and nfs_add_stats those from "enum nfs_stat_bytecounters" (in server->io_stats->bytes). Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Fixes: 5a254d08b086 ("nfs: replace nfs_add_stats with nfs_inc_stats...") Cc: stable@vger.kernel.org # 3.19+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-15VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells1-1/+1
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15NFS: Don't use d_inode as a variable nameDavid Howells1-4/+4
Don't use d_inode as a variable name as it now masks a function name. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-03nfs: add mirroring support to pgio layerWeston Andros Adamson1-5/+25
This patch adds mirrored write support to the pgio layer. The default is to use one mirror, but pgio callers may define callbacks to change this to any value up to the (arbitrarily selected) limit of 16. The basic idea is to break out members of nfs_pageio_descriptor that cannot be shared between mirrored DSes and put them in a new structure. Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03pnfs: Add nfs_rpc_ops in calls to nfs_initiate_pgioTom Haynes1-1/+2
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2014-11-25nfs: replace nfs_add_stats with nfs_inc_stats when add oneLi RongQing1-1/+1
Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-26nfs: get rid of duplicate dprintkWeston Andros Adamson1-6/+0
This was introduced by a merge error with my recent pgio patchset. Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-25nfs: merge nfs_pgio_data into _headerWeston Andros Adamson1-20/+22
struct nfs_pgio_data only exists as a member of nfs_pgio_header, but is passed around everywhere, because there used to be multiple _data structs per _header. Many of these functions then use the _data to find a pointer to the _header. This patch cleans this up by merging the nfs_pgio_data structure into nfs_pgio_header and passing nfs_pgio_header around instead. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-25nfs: move nfs_pgio_data and remove nfs_rw_headerWeston Andros Adamson1-3/+3
nfs_rw_header was used to allocate an nfs_pgio_header along with an nfs_pgio_data, because a _header would need at least one _data. Now there is only ever one nfs_pgio_data for each nfs_pgio_header -- move it to nfs_pgio_header and get rid of nfs_rw_header. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29nfs: support page groups in nfs_read_completionWeston Andros Adamson1-7/+17
nfs_read_completion relied on the fact that there was a 1:1 mapping of page to nfs_request, but this has now changed. Regions not covered by a request have already been zeroed elsewhere. Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29nfs: page group syncing in read pathWeston Andros Adamson1-5/+17
Operations that modify state for a whole page must be syncronized across all requests within a page group. In the read path, this is calling unlock_page and SetPageUptodate. Both of these functions should not be called until all requests in a page group have reached the point where they would call them. This patch should have no effect yet since all page groups currently have one request, but will come into play when pg_test functions are modified to split pages into sub-page regions. Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29nfs: add support for multiple nfs reqs per pageWeston Andros Adamson1-2/+2
Add "page groups" - a circular list of nfs requests (struct nfs_page) that all reference the same page. This gives nfs read and write paths the ability to account for sub-page regions independently. This somewhat follows the design of struct buffer_head's sub-page accounting. Only "head" requests are ever added/removed from the inode list in the buffered write path. "head" and "sub" requests are treated the same through the read path and the rest of the write/commit path. Requests are given an extra reference across the life of the list. Page groups are never rejoined after being split. If the read/write request fails and the client falls back to another path (ie revert to MDS in PNFS case), the already split requests are pushed through the recoalescing code again, which may split them further and then coalesce them into properly sized requests on the wire. Fragmentation shouldn't be a problem with the current design, because we flush all requests in page group when a non-contiguous request is added, so the only time resplitting should occur is on a resend of a read or write. This patch lays the groundwork for sub-page splitting, but does not actually do any splitting. For now all page groups have one request as pg_test functions don't yet split pages. There are several related patches that are needed support multiple requests per page group. Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29nfs: remove unused arg from nfs_create_requestWeston Andros Adamson1-3/+2
@inode is passed but not used. Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common nfs_pageio_ops structAnna Schumaker1-8/+2
At this point the read and write structures look identical, so combine them into something shared by both. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common generic_pg_pgios()Anna Schumaker1-24/+1
What we have here is two functions that look identical. Let's share some more code! Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common multiple_pgios() functionAnna Schumaker1-30/+2
Once again, these two functions look identical in the read and write case. Time to combine them together! Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common initiate_pgio() functionAnna Schumaker1-36/+6
Most of this code is the same for both the read and write paths, so combine everything and use the rw_ops when necessary. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a generic_pgio functionAnna Schumaker1-80/+1
These functions are almost identical on both the read and write side. FLUSH_COND_STABLE will never be set for the read path, so leaving it in the generic code won't hurt anything. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common pgio_error functionAnna Schumaker1-21/+4
At this point, the read and write versions of this function look identical so both should use the same function. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common rpcsetup function for reads and writesAnna Schumaker1-24/+2
Write adds a little bit of code dealing with flush flags, but since "how" will always be 0 when reading we can share the code. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common rpc_call_ops structAnna Schumaker1-9/+2
The read and write paths set up this struct in exactly the same way, so create a single shared struct. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common nfs_pgio_result_common functionAnna Schumaker1-17/+8
Combining these functions will let me make a single nfs_rw_common_ops struct (see the next patch). Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common pgio_rpc_prepare functionAnna Schumaker1-16/+3
The read and write paths do exactly the same thing for the rpc_prepare rpc_op. This patch combines them together into a single function. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common rw_header_alloc and rw_header_free functionAnna Schumaker1-21/+13
I create a new struct nfs_rw_ops to decide the differences between reads and writes. This struct will be set when initializing a new nfs_pgio_descriptor, and then passed on to the nfs_rw_header when a new header is allocated. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common pgio_alloc and pgio_release functionAnna Schumaker1-50/+4
These functions are identical for the read and write paths so they can be combined. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common read and write header structAnna Schumaker1-7/+7
The only difference is the write verifier field, but we can keep that for a little bit longer. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common read and write data structAnna Schumaker1-16/+16
At this point, the only difference between nfs_read_data and nfs_write_data is the write verifier. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common results structure for reads and writesAnna Schumaker1-1/+1
Reads and writes have very similar results. This patch combines the two structs together with comments to show where the differing fields are used. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29NFS: Create a common argument structure for reads and writesAnna Schumaker1-1/+1
Reads and writes have very similar arguments. This patch combines them together and documents the few fields used only by write. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29nfs: remove ->read_pageio_init from rpc opsChristoph Hellwig1-5/+14
The read_pageio_init method is just a very convoluted way to grab the right nfs_pageio_ops vector. The vector to chose is not a choice of protocol version, but just a pNFS vs MDS I/O choice that can simply be done inside nfs_pageio_init_read based on the presence of a layout driver, and a new force_mds flag to the special case of falling back to MDS I/O on a pNFS-capable volume. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-01-06NFS: dprintk() should not print negative fileids and inode numbersNiels de Vos1-6/+6
A fileid in NFS is a uint64. There are some occurrences where dprintk() outputs a signed fileid. This leads to confusion and more difficult to read debugging (negative fileids matching positive inode numbers). Signed-off-by: Niels de Vos <ndevos@redhat.com> CC: Santosh Pradhan <spradhan@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2013-09-04NFSv4: Don't try to recover NFSv4 locks when they are lost.NeilBrown1-3/+4
When an NFSv4 client loses contact with the server it can lose any locks that it holds. Currently when it reconnects to the server it simply tries to reclaim those locks. This might succeed even though some other client has held and released a lock in the mean time. So the first client might think the file is unchanged, but it isn't. This isn't good. If, when recovery happens, the locks cannot be claimed because some other client still holds the lock, then we get a message in the kernel logs, but the client can still write. So two clients can both think they have a lock and can both write at the same time. This is equally not good. There was a patch a while ago http://comments.gmane.org/gmane.linux.nfs/41917 which tried to address some of this, but it didn't seem to go anywhere. That patch would also send a signal to the process. That might be useful but for now this patch just causes writes to fail. For NFSv4 (unlike v2/v3) there is a strong link between the lock and the write request so we can fairly easily fail any IO of the lock is gone. While some applications might not expect this, it is still safer than allowing the write to succeed. Because this is a fairly big change in behaviour a module parameter, "recover_locks", is introduced which defaults to true (the current behaviour) but can be set to "false" to tell the client not to try to recover things that were lost. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-03-25NFS: Don't accept more reads/writes if the open context recovery failedTrond Myklebust1-0/+2
If the state recovery failed, we want to ensure that the application doesn't try to use the same file descriptor for more reads or writes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-01-04NFS: Ensure that we free the rpc_task after read and write cleanups are doneTrond Myklebust1-3/+7
This patch ensures that we free the rpc_task after the cleanup callbacks are done in order to avoid a deadlock problem that can be triggered if the callback needs to wait for another workqueue item to complete. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Weston Andros Adamson <dros@netapp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Bruce Fields <bfields@fieldses.org> Cc: stable@vger.kernel.org [>= 3.5]
2012-08-01Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds1-3/+3
Merge Andrew's second set of patches: - MM - a few random fixes - a couple of RTC leftovers * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits) rtc/rtc-88pm80x: remove unneed devm_kfree rtc/rtc-88pm80x: assign ret only when rtc_register_driver fails mm: hugetlbfs: close race during teardown of hugetlbfs shared page tables tmpfs: distribute interleave better across nodes mm: remove redundant initialization mm: warn if pg_data_t isn't initialized with zero mips: zero out pg_data_t when it's allocated memcg: gix memory accounting scalability in shrink_page_list mm/sparse: remove index_init_lock mm/sparse: more checks on mem_section number mm/sparse: optimize sparse_index_alloc memcg: add mem_cgroup_from_css() helper memcg: further prevent OOM with too many dirty pages memcg: prevent OOM with too many dirty pages mm: mmu_notifier: fix freed page still mapped in secondary MMU mm: memcg: only check anon swapin page charges for swap cache mm: memcg: only check swap cache pages for repeated charging mm: memcg: split swapin charge function into private and public part mm: memcg: remove needless !mm fixup to init_mm when charging mm: memcg: remove unneeded shmem charge type ...
2012-08-01nfs: teach the NFS client how to treat PG_swapcache pagesMel Gorman1-3/+3
Replace all relevant occurences of page->index and page->mapping in the NFS client with the new page_file_index() and page_file_mapping() functions. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Eric B Munson <emunson@mgebm.net> Cc: Eric Paris <eparis@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Neil Brown <neilb@suse.de> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Xiaotian Feng <dfeng@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31NFS: Convert v4 into a moduleBryan Schumaker1-0/+4
This patch exports symbols needed by the v4 module. In addition, I also switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or CONFIG_NFS_V4_MODULE are set. The module (nfs4.ko) will be created in the same directory as nfs.ko and will be automatically loaded the first time you try to mount over NFS v4. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-31NFS: Convert v2 into a moduleBryan Schumaker1-0/+1
The module (nfs2.ko) will be created in the same directory as nfs.ko and will be automatically loaded the first time you try to mount over NFS v2. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-06-29NFS: Create an read_pageio_init() functionBryan Schumaker1-13/+3
pNFS needs to select a read function based on the layout driver currently in use, so I let each NFS version decide how to best handle initializing reads. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-05-25NFSv4.1 add nfs_inode book keeping for mdsthresholdAndy Adamson1-0/+2
Keep track of the number of bytes read or written via buffered, direct, and mem-mapped i/o for use by mdsthreshold size_io hints. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-05-20NFSv4.1 set RPC_TASK_SOFTCONN for filelayout DS RPC callsAndy Adamson1-3/+3
RPC_TASK_SOFTCONN returns connection errors to the caller which allows the pNFS file layout to quickly try the MDS or perhaps another DS. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-05-04NFS: Fix sparse warningsTrond Myklebust1-1/+1
Fix the following sparse warnings: fs/nfs/direct.c:221:6: warning: symbol 'nfs_direct_readpage_release' was not declared. Should it be static? fs/nfs/read.c:38:43: warning: non-ANSI function declaration of function 'nfs_readhdr_alloc' fs/nfs/objlayout/objio_osd.c:214:5: warning: symbol '__alloc_objio_seg' was not declared. Should it be static? Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Fred Isaman <iisaman@netapp.com> Cc: Boaz Harrosh <bharrosh@panasas.com>
2012-05-01NFS: Simplify the nfs_read_completion functionsTrond Myklebust1-26/+18
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Fred Isaman <iisaman@netapp.com>
2012-05-01NFS: Clean up nfs read and write error pathsTrond Myklebust1-17/+21
Move the error handling for nfs_generic_pagein() into a single function. Ditto for nfs_generic_flush(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Fred Isaman <iisaman@netapp.com>
2012-05-01NFS: Read cleanupsTrond Myklebust1-9/+4
Remove unused variables, and reformat some code. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Fred Isaman <iisaman@netapp.com>
2012-04-27NFS: rewrite directio read to use async coalesce codeFred Isaman1-5/+5
This also has the advantage that it allows directio to use pnfs. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-04-27NFS: create completion structure to pass into page_init functionsFred Isaman1-14/+22
Factors out the code that will need to change when directio starts using these code paths. This will allow directio to use the generic pagein and flush routines Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-04-27NFS: merge _full and _partial read rpc_opsFred Isaman1-181/+157
Decouple nfs_pgio_header and nfs_read_data, and have (possibly multiple) nfs_read_datas each take a refcount on nfs_pgio_header. For the moment keeps nfs_read_header as a way to preallocate a single nfs_read_data with the nfs_pgio_header. The code doesn't need this, and would be prettier without, but given the amount of churn I am already introducing I didn't want to play with tuning new mempools. This also fixes bug in pnfs_ld_handle_read_error. In the case of desc->pg_bsize < PAGE_CACHE_SIZE, the pages list was empty, causing replay attempt to do nothing. Signed-off-by: Fred Isaman <iisaman@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>