nfs: use > 1 request to handle bsize < PAGE_SIZE
Use the newly added support for multiple requests per page for
rsize/wsize < PAGE_SIZE, instead of having multiple read / write
data structures per pageio header.
This allows us to get rid of nfs_pgio_multi.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 838f7c9..ec4311d 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -443,21 +443,13 @@
size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
struct nfs_page *prev, struct nfs_page *req)
{
- if (!prev)
- return req->wb_bytes;
- /*
- * FIXME: ideally we should be able to coalesce all requests
- * that are not block boundary aligned, but currently this
- * is problematic for the case of bsize < PAGE_CACHE_SIZE,
- * since nfs_flush_multi and nfs_pagein_multi assume you
- * can have only one struct nfs_page.
- */
- if (desc->pg_bsize < PAGE_SIZE)
+ if (desc->pg_count > desc->pg_bsize) {
+ /* should never happen */
+ WARN_ON_ONCE(1);
return 0;
+ }
- if (desc->pg_count + req->wb_bytes <= desc->pg_bsize)
- return req->wb_bytes;
- return 0;
+ return min(desc->pg_bsize - desc->pg_count, (size_t)req->wb_bytes);
}
EXPORT_SYMBOL_GPL(nfs_generic_pg_test);
@@ -766,50 +758,6 @@
}
/*
- * Generate multiple small requests to read or write a single
- * contiguous dirty on one page.
- */
-static int nfs_pgio_multi(struct nfs_pageio_descriptor *desc,
- struct nfs_pgio_header *hdr)
-{
- struct nfs_page *req = hdr->req;
- struct page *page = req->wb_page;
- struct nfs_pgio_data *data;
- size_t wsize = desc->pg_bsize, nbytes;
- unsigned int offset;
- int requests = 0;
- struct nfs_commit_info cinfo;
-
- nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq);
-
- if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
- (desc->pg_moreio || nfs_reqs_to_commit(&cinfo) ||
- desc->pg_count > wsize))
- desc->pg_ioflags &= ~FLUSH_COND_STABLE;
-
- offset = 0;
- nbytes = desc->pg_count;
- do {
- size_t len = min(nbytes, wsize);
-
- data = nfs_pgio_data_alloc(hdr, 1);
- if (!data)
- return nfs_pgio_error(desc, hdr);
- data->pages.pagevec[0] = page;
- nfs_pgio_rpcsetup(data, len, offset, desc->pg_ioflags, &cinfo);
- list_add(&data->list, &hdr->rpc_list);
- requests++;
- nbytes -= len;
- offset += len;
- } while (nbytes != 0);
-
- nfs_list_remove_request(req);
- nfs_list_add_request(req, &hdr->pages);
- desc->pg_rpc_callops = &nfs_pgio_common_ops;
- return 0;
-}
-
-/*
* Create an RPC task for the given read or write request and kick it.
* The page must have been locked by the caller.
*
@@ -817,8 +765,8 @@
* This is the case if nfs_updatepage detects a conflicting request
* that has been written but not committed.
*/
-static int nfs_pgio_one(struct nfs_pageio_descriptor *desc,
- struct nfs_pgio_header *hdr)
+int nfs_generic_pgio(struct nfs_pageio_descriptor *desc,
+ struct nfs_pgio_header *hdr)
{
struct nfs_page *req;
struct page **pages;
@@ -850,6 +798,7 @@
desc->pg_rpc_callops = &nfs_pgio_common_ops;
return 0;
}
+EXPORT_SYMBOL_GPL(nfs_generic_pgio);
static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc)
{
@@ -875,15 +824,6 @@
return ret;
}
-int nfs_generic_pgio(struct nfs_pageio_descriptor *desc,
- struct nfs_pgio_header *hdr)
-{
- if (desc->pg_bsize < PAGE_CACHE_SIZE)
- return nfs_pgio_multi(desc, hdr);
- return nfs_pgio_one(desc, hdr);
-}
-EXPORT_SYMBOL_GPL(nfs_generic_pgio);
-
static bool nfs_match_open_context(const struct nfs_open_context *ctx1,
const struct nfs_open_context *ctx2)
{
@@ -925,7 +865,9 @@
return false;
}
size = pgio->pg_ops->pg_test(pgio, prev, req);
- WARN_ON_ONCE(size && size != req->wb_bytes);
+ WARN_ON_ONCE(size > req->wb_bytes);
+ if (size && size < req->wb_bytes)
+ req->wb_bytes = size;
return size > 0;
}