Commit Graph

107 Commits

Author SHA1 Message Date
Trond Myklebust b6ee8cd264 NFS: Get rid of the nfs_rdata_mempool
We don't need a mempool in order to guarantee reliable NFS read performance.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-19 13:58:38 -07:00
Trond Myklebust fba730050d NFS: Don't rely on PageError in nfs_readpage_release_partial
Don't rely on the PageError flag to tell us if one of the partial reads of
the page failed. Instead, replace that with a dedicated flag in the
struct nfs_page.

Then clean out redundant uses of the PageError flag: the VM no longer
checks it for reads.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-19 13:58:38 -07:00
Trond Myklebust fbb5a9abf0 NFS: Get rid of unnecessary calls to ClearPageError() in read code
The generic file read code does that for us anyway.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-19 13:58:37 -07:00
Trond Myklebust d00c5d4386 NFS: Get rid of nfs_restart_rpc()
It can trivially be replaced with rpc_restart_call_prepare.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-19 13:58:30 -07:00
Peng Tao 9b7eecdcfe pnfs: recoalesce when ld read pagelist fails
For pnfs pagelist read failure, we need to pg_recoalesce and resend IO to
mds.

Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Cc: stable@kernel.org [3.0]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-18 09:08:14 -07:00
Stephen Rothwell 5f00bcb38e Merge branch 'master' into devel and apply fixup from Stephen Rothwell:
vfs/nfs: fixup for nfs_open_context change

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-25 14:53:52 -04:00
Al Viro 3d4ff43d89 nfs_open_context doesn't need struct path either
just dentry, please...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:44 -04:00
Trond Myklebust 1f9453578f NFS: Clean up - simplify the switch to read/write-through-MDS
Use nfs_pageio_reset_read_mds and nfs_pageio_reset_write_mds instead of
completely reinitialising the struct nfs_pageio_descriptor.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:12:22 -04:00
Trond Myklebust 493292ddc7 NFS: Move the pnfs read code into pnfs.c
...and ensure that we recoalese to take into account differences in
block sizes when falling back to read through the MDS.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:12:21 -04:00
Trond Myklebust d097971d8a NFS: Use the nfs_pageio_descriptor->pg_bsize in the read/write request
Instead of looking up the rsize and wsize, the routines that generate the
RPC requests should really be using the pg_bsize, since that is what we
use when deciding whether or not to coalesce write requests...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:12:20 -04:00
Trond Myklebust 50828d7e67 NFS: Cache rpc_ops in struct nfs_pageio_descriptor
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:12:20 -04:00
Trond Myklebust 275acaafd4 NFS: Clean up: split out the RPC transmission from nfs_pagein_multi/one
...and do the same for nfs_flush_multi/one.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:12:17 -04:00
Peng Tao 3b6091846d NFS: fix return value of nfs_pagein_one/nfs_flush_one
Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15 09:11:28 -04:00
Trond Myklebust 6e4efd5685 NFS: Clean up nfs_read_rpcsetup and nfs_write_rpcsetup
Split them up into two parts: one which sets up the struct nfs_read/write_data,
the other which sets up the actual RPC call or pNFS call.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:42:02 -04:00
Andy Adamson 7c24d9489f NFSv4.1: File layout only supports whole file layouts
Ask for whole file layouts. Until support for layout segments is fully
supported in the file layout code, discard non-whole file layouts.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:40:28 -04:00
Trond Myklebust e885de1a5b NFSv4.1: Fall back to ordinary i/o through the mds if we have no layout segment
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:40:28 -04:00
Trond Myklebust d8007d4dd6 NFSv4.1: Add an initialisation callback for pNFS
Ensure that we always get a layout before setting up the i/o request.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:40:28 -04:00
Trond Myklebust 1751c3638f NFS: Cleanup of the nfs_pageio code in preparation for a pnfs bugfix
We need to ensure that the layouts are set up before we can decide to
coalesce requests. To do so, we want to further split up the struct
nfs_pageio_descriptor operations into an initialisation callback, a
coalescing test callback, and a 'do i/o' callback.

This patch cleans up the existing callback methods before adding the
'initialisation' callback.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:40:28 -04:00
Benny Halevy dfed206b88 NFSv4.1: unify pnfs_pageio_init functions
Use common code for pnfs_pageio_init_{read,write} and use
a common generic pg_test function.

Note that this function always assumes the the layout driver's
pg_test method is implemented.

[Fix BUG]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:56:43 +03:00
Benny Halevy fb3296eb46 pnfs: Use byte-range for layoutget
Add offset and count parameters to pnfs_update_layout and use them to get
the layout in the pageio path.

Order cache layout segments in the following order:
* offset (ascending)
* length (descending)
* iomode (RW before READ)

Test byte range against the layout segment in use in pnfs_{read,write}_pg_test
so not to coalesce pages not using the same layout segment.

[fix lseg ordering]
[clean up pnfs_find_lseg lseg arg]
[remove unnecessary FIXME]
[fix ordering in pnfs_insert_layout]
[clean up pnfs_insert_layout]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:52:32 +03:00
Trond Myklebust a75b9df9d3 NFSv4.1: Ensure that layoutget uses the correct gfp modes
Currently, writebacks may end up recursing back into the filesystem due to
GFP_KERNEL direct reclaims in the pnfs subsystem.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-05-11 22:52:13 -04:00
Stephen Rothwell 8f68cd42d8 nfs: BKL is no longer needed, so remove the include
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-15 08:44:35 -04:00
Fred Isaman 36fe432d33 NFSv4.1: Clear lseg pointer in ->doio function
Now that we have access to the pointer, clear it immediately after
the put, instead of in caller.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:45 -05:00
Fred Isaman c76069bda0 NFSv4.1: rearrange ->doio args
This will make it possible to clear the lseg pointer in the same
function as it is put, instead of in the caller nfs_pageio_doio().

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Andy Adamson cbdabc7f8b NFSv4.1: filelayout async error handler
Use our own async error handler.
Mark the layout as failed and retry i/o through the MDS on specified errors.

Update the mds_offset in nfs_readpage_retry so that a failed short-read retry
to a DS gets correctly resent through the MDS.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:43 -05:00
Andy Adamson dc70d7b318 NFSv4.1: filelayout read
Attempt a pNFS file layout read by setting up the nfs_read_data struct and
calling nfs_initiate_read with the data server rpc client and the
filelayout rpc call ops.

Error handling is implemented in a subsequent patch.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Tested-by: Guo Mingyang <guomingyang@nrchpc.ac.cn>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:43 -05:00
Andy Adamson 64419a9b20 NFSv4.1: generic read
Separate the rpc run portion of nfs_read_rpcsetup into a new function
nfs_initiate_read that is called for normal NFS I/O.

Add a pNFS read_pagelist function that is called instead of nfs_intitate_read
for pNFS reads.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Mike Sager <sager@netapp.com>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:42 -05:00
Fred Isaman bae724ef95 NFSv4.1: shift pnfs_update_layout locations
Move the pnfs_update_layout call location to nfs_pageio_do_add_request().
Grab the lseg sent in the doio function to nfs_read_rpcsetup and attach
it to each nfs_read_data so it can be sent to the layout driver.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:42 -05:00
Fred Isaman 94ad1c80e2 NFSv4.1: coelesce across layout stripes
Add a pg_test layout driver hook which is used to avoid coelescing I/O across
layout stripes.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:42 -05:00
Trond Myklebust 2df485a774 nfs: remove extraneous and problematic calls to nfs_clear_request
When a nfs_page is freed, nfs_free_request is called which also calls
nfs_clear_request to clean out the lock and open contexts and free the
pagecache page.

However, a couple of places in the nfs code call nfs_clear_request
themselves. What happens here if the refcount on the request is still high?
We'll be releasing contexts and freeing pointers while the request is
possibly still in use.

Remove those bare calls to nfs_clear_context. That should only be done when
the request is being freed.

Note that when doing this, we need to watch out for tests of req->wb_page.
Previously, nfs_set_page_tag_locked() and nfs_clear_page_tag_locked()
would check the value of req->wb_page to figure out if the page is mapped
into the nfsi->nfs_page_tree. We now indicate the page is mapped using
the new bit PG_MAPPED in req->wb_flags .

Reported-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-07 23:02:44 -05:00
Benny Halevy e5e940170b NFS: create and destroy inode's layout cache
At the start of the io paths, try to grab the relevant layout
information.  This will initiate the inode's layout cache, but
stubs ensure the cache stays empty.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Dean Hildebrand <dhildebz@umich.edu>
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-24 18:07:10 -04:00
Benny Halevy dfb4f30983 NFSv4.1: keep seq_res.sr_slot as pointer rather than an index
Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs.  Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-24 09:17:01 -04:00
Trond Myklebust f11ac8db5d NFSv4: Ensure that we track the NFSv4 lock state in read/write requests.
This patch fixes bugzilla entry 14501:
  https://bugzilla.kernel.org/show_bug.cgi?id=14501

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-07-30 14:41:56 -04:00
Trond Myklebust 035168ab39 NFSv4.1: Make nfs4_setup_sequence take a nfs_server argument
In anticipation of the day when we have per-filesystem sessions, and also
in order to allow the session to change in the event of a filesystem
migration event.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-06-22 13:24:02 -04:00
Trond Myklebust 93870d76fe NFS: Read requests can use GFP_KERNEL.
There is no danger of deadlock should the allocation trigger page
writeback.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14 15:09:34 -04:00
Trond Myklebust 0110ee152b NFS: Fix up the declaration of nfs4_restart_rpc when NFSv4 not configured
Also rename it: it is used in generic code, and so should not have a 'nfs4'
prefix.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-07 09:00:24 -05:00
Trond Myklebust d61e612a72 NFSv41: Clean up slot table management
We no longer need to maintain a distinction between nfs41_sequence_done and
nfs41_sequence_free_slot.

This fixes a number of slot table leakages in the NFSv4.1 code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-05 19:32:19 -05:00
Andy Adamson e608e79f1b nfs41: call free slot from nfs4_restart_rpc
nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation
errors.
No reason to inline nfs4_restart_rpc

Reported-by: Trond Myklebust <trond.myklebust@netapp.com>

nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the
error handler, and the slot is not freed prior to restarting in the rpc_prepare
state during session reset.

Fix this by moving the call to nfs41_sequence_free_slot from the error
path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test
for NFS4CLNT_SESSION_SETUP.
Always free slot and goto the rpc prepare state on async errors.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-04 15:55:29 -05:00
Trond Myklebust 1ae88b2e44 NFS: Fix an O_DIRECT Oops...
We can't call nfs_readdata_release()/nfs_writedata_release() without
first initialising and referencing args.context. Doing so inside
nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment()
causes an Oops.

We should rather be calling nfs_readdata_free()/nfs_writedata_free() in
those cases.

Looking at the O_DIRECT code, the "struct nfs_direct_req" is already
referencing the nfs_open_context for us. Since the readdata and writedata
structures carry a reference to that, we can simplify things by getting rid
of the extra nfs_open_context references, so that we can replace all
instances of nfs_readdata_release()/nfs_writedata_release().

Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-12 08:21:39 -07:00
Alexey Dobriyan 405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Andy Adamson eedc020e71 nfs41: use rpc prepare call state for session reset
[nfs41: change nfs4_restart_rpc argument]
[nfs41: check for session not minorversion]
[nfs41: trigger the state manager for session reset]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[always define nfs4_restart_rpc]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 12:25:07 -07:00
Andy Adamson f11c88af26 nfs41: read sequence setup/done support
Implement the read rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.

Call nfs4_sequence_done from respective rpc_call_done methods.

Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move the nfs4_sequence_free_slot call in nfs_readpage_retry from]
[nfs41: separate free slot from sequence done]
[remove nfs_readargs.nfs_server, use calldata->inode instead]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 10:46:48 -07:00
Andy Adamson 5f7dbd5c75 nfs41: set up seq_res.sr_slotid
Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE.

[was nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
[pulled definition of struct nfs4_sequence_res.sr_slotid to here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 10:46:30 -07:00
David Howells 7f8e05f60c NFS: Store pages from an NFS inode into a local cache
Store pages from an NFS inode into the cache data storage object associated
with that inode.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:45 +01:00
David Howells 9a9fc1c033 NFS: Read pages from FS-Cache into an NFS inode
Read pages from an FS-Cache data storage object representing an inode into an
NFS inode.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:44 +01:00
David Howells f42b293d6d NFS: nfs_readpage_async() needs to be accessible as a fallback for local caching
nfs_readpage_async() needs to be non-static so that it can be used as a
fallback for the local on-disk caching should an EIO crop up when reading the
cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:44 +01:00
Wu Fengguang 136221fc32 nfs: remove redundant tests on reading new pages
aops->readpages() and its NFS helper readpage_async_filler() will only
be called to do readahead I/O for newly allocated pages. So it's not
necessary to test for the always 0 dirty/uptodate page flags.

The removal of nfs_wb_page() call also fixes a readahead bug: the NFS
readahead has been synchronous since 2.6.23, because that call will
clear PG_readahead, which is the reminder for asynchronous readahead.

More background: the PG_readahead page flag is shared with PG_reclaim,
one for read path and the other for write path. clear_page_dirty_for_io()
unconditionally clears PG_readahead to prevent possible readahead residuals,
assuming itself to be always called in the write path. However, NFS is one
and the only exception in that it _always_ calls clear_page_dirty_for_io()
in the read path, i.e. for readpages()/readpage().

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23 15:21:30 -05:00
Harvey Harrison 3110ff8048 nfs: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16 09:43:29 -07:00
Trond Myklebust dbae4c73f0 NFS: Ensure that rpc_run_task() errors are propagated back to the caller
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:53:08 -04:00
Trond Myklebust fdd1e74c89 NFS: Ensure that the read code cleans up properly when rpc_run_task() fails
In the case of readpage() we need to ensure that the pages get unlocked,
and that the error is flagged.

In the case of O_DIRECT, we need to ensure that the pages are all released.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:53:01 -04:00