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Diffstat (limited to 'fs/nfs/read.c')
-rw-r--r--fs/nfs/read.c122
1 files changed, 81 insertions, 41 deletions
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 624ca7146b6..41c2ffee24f 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -51,14 +51,11 @@ struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
if (p) {
memset(p, 0, sizeof(*p));
INIT_LIST_HEAD(&p->pages);
- if (pagecount < NFS_PAGEVEC_SIZE)
- p->pagevec = &p->page_array[0];
+ if (pagecount <= ARRAY_SIZE(p->page_array))
+ p->pagevec = p->page_array;
else {
- size_t size = ++pagecount * sizeof(struct page *);
- p->pagevec = kmalloc(size, GFP_NOFS);
- if (p->pagevec) {
- memset(p->pagevec, 0, size);
- } else {
+ p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS);
+ if (!p->pagevec) {
mempool_free(p, nfs_rdata_mempool);
p = NULL;
}
@@ -104,6 +101,28 @@ int nfs_return_empty_page(struct page *page)
return 0;
}
+static void nfs_readpage_truncate_uninitialised_page(struct nfs_read_data *data)
+{
+ unsigned int remainder = data->args.count - data->res.count;
+ unsigned int base = data->args.pgbase + data->res.count;
+ unsigned int pglen;
+ struct page **pages;
+
+ if (data->res.eof == 0 || remainder == 0)
+ return;
+ /*
+ * Note: "remainder" can never be negative, since we check for
+ * this in the XDR code.
+ */
+ pages = &data->args.pages[base >> PAGE_CACHE_SHIFT];
+ base &= ~PAGE_CACHE_MASK;
+ pglen = PAGE_CACHE_SIZE - base;
+ if (pglen < remainder)
+ memclear_highpage_flush(*pages, base, pglen);
+ else
+ memclear_highpage_flush(*pages, base, remainder);
+}
+
/*
* Read a page synchronously.
*/
@@ -177,11 +196,9 @@ static int nfs_readpage_sync(struct nfs_open_context *ctx, struct inode *inode,
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
spin_unlock(&inode->i_lock);
- if (count)
- memclear_highpage_flush(page, rdata->args.pgbase, count);
- SetPageUptodate(page);
- if (PageError(page))
- ClearPageError(page);
+ nfs_readpage_truncate_uninitialised_page(rdata);
+ if (rdata->res.eof || rdata->res.count == rdata->args.count)
+ SetPageUptodate(page);
result = 0;
io_error:
@@ -436,20 +453,12 @@ static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata)
struct nfs_page *req = data->req;
struct page *page = req->wb_page;
+ if (likely(task->tk_status >= 0))
+ nfs_readpage_truncate_uninitialised_page(data);
+ else
+ SetPageError(page);
if (nfs_readpage_result(task, data) != 0)
return;
- if (task->tk_status >= 0) {
- unsigned int request = data->args.count;
- unsigned int result = data->res.count;
-
- if (result < request) {
- memclear_highpage_flush(page,
- data->args.pgbase + result,
- request - result);
- }
- } else
- SetPageError(page);
-
if (atomic_dec_and_test(&req->wb_complete)) {
if (!PageError(page))
SetPageUptodate(page);
@@ -462,6 +471,40 @@ static const struct rpc_call_ops nfs_read_partial_ops = {
.rpc_release = nfs_readdata_release,
};
+static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data)
+{
+ unsigned int count = data->res.count;
+ unsigned int base = data->args.pgbase;
+ struct page **pages;
+
+ if (unlikely(count == 0))
+ return;
+ pages = &data->args.pages[base >> PAGE_CACHE_SHIFT];
+ base &= ~PAGE_CACHE_MASK;
+ count += base;
+ for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++)
+ SetPageUptodate(*pages);
+ /*
+ * Was this an eof or a short read? If the latter, don't mark the page
+ * as uptodate yet.
+ */
+ if (count > 0 && (data->res.eof || data->args.count == data->res.count))
+ SetPageUptodate(*pages);
+}
+
+static void nfs_readpage_set_pages_error(struct nfs_read_data *data)
+{
+ unsigned int count = data->args.count;
+ unsigned int base = data->args.pgbase;
+ struct page **pages;
+
+ pages = &data->args.pages[base >> PAGE_CACHE_SHIFT];
+ base &= ~PAGE_CACHE_MASK;
+ count += base;
+ for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++)
+ SetPageError(*pages);
+}
+
/*
* This is the callback from RPC telling us whether a reply was
* received or some error occurred (timeout or socket shutdown).
@@ -469,27 +512,24 @@ static const struct rpc_call_ops nfs_read_partial_ops = {
static void nfs_readpage_result_full(struct rpc_task *task, void *calldata)
{
struct nfs_read_data *data = calldata;
- unsigned int count = data->res.count;
+ /*
+ * Note: nfs_readpage_result may change the values of
+ * data->args. In the multi-page case, we therefore need
+ * to ensure that we call the next nfs_readpage_set_page_uptodate()
+ * first in the multi-page case.
+ */
+ if (likely(task->tk_status >= 0)) {
+ nfs_readpage_truncate_uninitialised_page(data);
+ nfs_readpage_set_pages_uptodate(data);
+ } else
+ nfs_readpage_set_pages_error(data);
if (nfs_readpage_result(task, data) != 0)
return;
while (!list_empty(&data->pages)) {
struct nfs_page *req = nfs_list_entry(data->pages.next);
- struct page *page = req->wb_page;
- nfs_list_remove_request(req);
- if (task->tk_status >= 0) {
- if (count < PAGE_CACHE_SIZE) {
- if (count < req->wb_bytes)
- memclear_highpage_flush(page,
- req->wb_pgbase + count,
- req->wb_bytes - count);
- count = 0;
- } else
- count -= PAGE_CACHE_SIZE;
- SetPageUptodate(page);
- } else
- SetPageError(page);
+ nfs_list_remove_request(req);
nfs_readpage_release(req);
}
}
@@ -654,7 +694,7 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
return ret;
}
-int nfs_init_readpagecache(void)
+int __init nfs_init_readpagecache(void)
{
nfs_rdata_cachep = kmem_cache_create("nfs_read_data",
sizeof(struct nfs_read_data),
@@ -671,7 +711,7 @@ int nfs_init_readpagecache(void)
return 0;
}
-void nfs_destroy_readpagecache(void)
+void __exit nfs_destroy_readpagecache(void)
{
mempool_destroy(nfs_rdata_mempool);
if (kmem_cache_destroy(nfs_rdata_cachep))