NFS: create common nfs_pgio_header for both read and write
In order to avoid duplicating all the data in nfs_read_data whenever we
split it up into multiple RPC calls (either due to a short read result
or due to rsize < PAGE_SIZE), we split out the bits that are the same
per RPC call into a separate "header" structure.
The goal this patch moves towards is to have a single header
refcounted by several rpc_data structures. Thus, want to always refer
from rpc_data to the header, and not the other way. This patch comes
close to that ideal, but the directio code currently needs some
special casing, isolated in the nfs_direct_[read_write]hdr_release()
functions. This will be dealt with in a future patch.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
index 4bff4a3..fbf4874 100644
--- a/fs/nfs/objlayout/objio_osd.c
+++ b/fs/nfs/objlayout/objio_osd.c
@@ -440,11 +440,12 @@
int objio_read_pagelist(struct nfs_read_data *rdata)
{
+ struct nfs_pgio_header *hdr = rdata->header;
struct objio_state *objios;
int ret;
- ret = objio_alloc_io_state(NFS_I(rdata->inode)->layout, true,
- rdata->lseg, rdata->args.pages, rdata->args.pgbase,
+ ret = objio_alloc_io_state(NFS_I(hdr->inode)->layout, true,
+ hdr->lseg, rdata->args.pages, rdata->args.pgbase,
rdata->args.offset, rdata->args.count, rdata,
GFP_KERNEL, &objios);
if (unlikely(ret))
@@ -483,12 +484,12 @@
{
struct objio_state *objios = priv;
struct nfs_write_data *wdata = objios->oir.rpcdata;
+ struct address_space *mapping = wdata->header->inode->i_mapping;
pgoff_t index = offset / PAGE_SIZE;
- struct page *page = find_get_page(wdata->inode->i_mapping, index);
+ struct page *page = find_get_page(mapping, index);
if (!page) {
- page = find_or_create_page(wdata->inode->i_mapping,
- index, GFP_NOFS);
+ page = find_or_create_page(mapping, index, GFP_NOFS);
if (unlikely(!page)) {
dprintk("%s: grab_cache_page Failed index=0x%lx\n",
__func__, index);
@@ -518,11 +519,12 @@
int objio_write_pagelist(struct nfs_write_data *wdata, int how)
{
+ struct nfs_pgio_header *hdr = wdata->header;
struct objio_state *objios;
int ret;
- ret = objio_alloc_io_state(NFS_I(wdata->inode)->layout, false,
- wdata->lseg, wdata->args.pages, wdata->args.pgbase,
+ ret = objio_alloc_io_state(NFS_I(hdr->inode)->layout, false,
+ hdr->lseg, wdata->args.pages, wdata->args.pgbase,
wdata->args.offset, wdata->args.count, wdata, GFP_NOFS,
&objios);
if (unlikely(ret))
diff --git a/fs/nfs/objlayout/objlayout.c b/fs/nfs/objlayout/objlayout.c
index 595c5fc..8746135 100644
--- a/fs/nfs/objlayout/objlayout.c
+++ b/fs/nfs/objlayout/objlayout.c
@@ -258,7 +258,7 @@
if (status >= 0)
rdata->res.count = status;
else
- rdata->pnfs_error = status;
+ rdata->header->pnfs_error = status;
objlayout_iodone(oir);
/* must not use oir after this point */
@@ -279,12 +279,14 @@
enum pnfs_try_status
objlayout_read_pagelist(struct nfs_read_data *rdata)
{
+ struct nfs_pgio_header *hdr = rdata->header;
+ struct inode *inode = hdr->inode;
loff_t offset = rdata->args.offset;
size_t count = rdata->args.count;
int err;
loff_t eof;
- eof = i_size_read(rdata->inode);
+ eof = i_size_read(inode);
if (unlikely(offset + count > eof)) {
if (offset >= eof) {
err = 0;
@@ -297,17 +299,17 @@
}
rdata->res.eof = (offset + count) >= eof;
- _fix_verify_io_params(rdata->lseg, &rdata->args.pages,
+ _fix_verify_io_params(hdr->lseg, &rdata->args.pages,
&rdata->args.pgbase,
rdata->args.offset, rdata->args.count);
dprintk("%s: inode(%lx) offset 0x%llx count 0x%Zx eof=%d\n",
- __func__, rdata->inode->i_ino, offset, count, rdata->res.eof);
+ __func__, inode->i_ino, offset, count, rdata->res.eof);
err = objio_read_pagelist(rdata);
out:
if (unlikely(err)) {
- rdata->pnfs_error = err;
+ hdr->pnfs_error = err;
dprintk("%s: Returned Error %d\n", __func__, err);
return PNFS_NOT_ATTEMPTED;
}
@@ -340,7 +342,7 @@
wdata->res.count = status;
wdata->verf.committed = oir->committed;
} else {
- wdata->pnfs_error = status;
+ wdata->header->pnfs_error = status;
}
objlayout_iodone(oir);
/* must not use oir after this point */
@@ -363,15 +365,16 @@
objlayout_write_pagelist(struct nfs_write_data *wdata,
int how)
{
+ struct nfs_pgio_header *hdr = wdata->header;
int err;
- _fix_verify_io_params(wdata->lseg, &wdata->args.pages,
+ _fix_verify_io_params(hdr->lseg, &wdata->args.pages,
&wdata->args.pgbase,
wdata->args.offset, wdata->args.count);
err = objio_write_pagelist(wdata, how);
if (unlikely(err)) {
- wdata->pnfs_error = err;
+ hdr->pnfs_error = err;
dprintk("%s: Returned Error %d\n", __func__, err);
return PNFS_NOT_ATTEMPTED;
}