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Diffstat (limited to 'fs/nfs/read.c')
-rw-r--r--fs/nfs/read.c204
1 files changed, 91 insertions, 113 deletions
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index eb854f1f86e2..d2b6dce1f99f 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -74,6 +74,24 @@ void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
}
EXPORT_SYMBOL_GPL(nfs_pageio_init_read);
+static void nfs_pageio_complete_read(struct nfs_pageio_descriptor *pgio,
+ struct inode *inode)
+{
+ struct nfs_pgio_mirror *pgm;
+ unsigned long npages;
+
+ nfs_pageio_complete(pgio);
+
+ /* It doesn't make sense to do mirrored reads! */
+ WARN_ON_ONCE(pgio->pg_mirror_count != 1);
+
+ pgm = &pgio->pg_mirrors[0];
+ NFS_I(inode)->read_io += pgm->pg_bytes_written;
+ npages = (pgm->pg_bytes_written + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ nfs_add_stats(inode, NFSIOS_READPAGES, npages);
+}
+
+
void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio)
{
struct nfs_pgio_mirror *mirror;
@@ -114,41 +132,10 @@ static void nfs_readpage_release(struct nfs_page *req, int error)
nfs_release_request(req);
}
-int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode,
- struct page *page)
-{
- struct nfs_page *new;
- unsigned int len;
+struct nfs_readdesc {
struct nfs_pageio_descriptor pgio;
- struct nfs_pgio_mirror *pgm;
-
- len = nfs_page_length(page);
- if (len == 0)
- return nfs_return_empty_page(page);
- new = nfs_create_request(ctx, page, 0, len);
- if (IS_ERR(new)) {
- unlock_page(page);
- return PTR_ERR(new);
- }
- if (len < PAGE_SIZE)
- zero_user_segment(page, len, PAGE_SIZE);
-
- nfs_pageio_init_read(&pgio, inode, false,
- &nfs_async_read_completion_ops);
- if (!nfs_pageio_add_request(&pgio, new)) {
- nfs_list_remove_request(new);
- nfs_readpage_release(new, pgio.pg_error);
- }
- nfs_pageio_complete(&pgio);
-
- /* It doesn't make sense to do mirrored reads! */
- WARN_ON_ONCE(pgio.pg_mirror_count != 1);
-
- pgm = &pgio.pg_mirrors[0];
- NFS_I(inode)->read_io += pgm->pg_bytes_written;
-
- return pgio.pg_error < 0 ? pgio.pg_error : 0;
-}
+ struct nfs_open_context *ctx;
+};
static void nfs_page_group_set_uptodate(struct nfs_page *req)
{
@@ -171,8 +158,7 @@ static void nfs_read_completion(struct nfs_pgio_header *hdr)
if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) {
/* note: regions of the page not covered by a
- * request are zeroed in nfs_readpage_async /
- * readpage_async_filler */
+ * request are zeroed in readpage_async_filler */
if (bytes > hdr->good_bytes) {
/* nothing in this request was good, so zero
* the full extent of the request */
@@ -304,6 +290,38 @@ static void nfs_readpage_result(struct rpc_task *task,
nfs_readpage_retry(task, hdr);
}
+static int
+readpage_async_filler(void *data, struct page *page)
+{
+ struct nfs_readdesc *desc = data;
+ struct nfs_page *new;
+ unsigned int len;
+ int error;
+
+ len = nfs_page_length(page);
+ if (len == 0)
+ return nfs_return_empty_page(page);
+
+ new = nfs_create_request(desc->ctx, page, 0, len);
+ if (IS_ERR(new))
+ goto out_error;
+
+ if (len < PAGE_SIZE)
+ zero_user_segment(page, len, PAGE_SIZE);
+ if (!nfs_pageio_add_request(&desc->pgio, new)) {
+ nfs_list_remove_request(new);
+ error = desc->pgio.pg_error;
+ nfs_readpage_release(new, error);
+ goto out;
+ }
+ return 0;
+out_error:
+ error = PTR_ERR(new);
+ unlock_page(page);
+out:
+ return error;
+}
+
/*
* Read a page over NFS.
* We read the page synchronously in the following case:
@@ -312,14 +330,13 @@ static void nfs_readpage_result(struct rpc_task *task,
*/
int nfs_readpage(struct file *file, struct page *page)
{
- struct nfs_open_context *ctx;
+ struct nfs_readdesc desc;
struct inode *inode = page_file_mapping(page)->host;
- int error;
+ int ret;
dprintk("NFS: nfs_readpage (%p %ld@%lu)\n",
page, PAGE_SIZE, page_index(page));
nfs_inc_stats(inode, NFSIOS_VFSREADPAGE);
- nfs_add_stats(inode, NFSIOS_READPAGES, 1);
/*
* Try to flush any pending writes to the file..
@@ -328,93 +345,59 @@ int nfs_readpage(struct file *file, struct page *page)
* be any new pending writes generated at this point
* for this page (other pages can be written to).
*/
- error = nfs_wb_page(inode, page);
- if (error)
+ ret = nfs_wb_page(inode, page);
+ if (ret)
goto out_unlock;
if (PageUptodate(page))
goto out_unlock;
- error = -ESTALE;
+ ret = -ESTALE;
if (NFS_STALE(inode))
goto out_unlock;
if (file == NULL) {
- error = -EBADF;
- ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
- if (ctx == NULL)
+ ret = -EBADF;
+ desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
+ if (desc.ctx == NULL)
goto out_unlock;
} else
- ctx = get_nfs_open_context(nfs_file_open_context(file));
+ desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
if (!IS_SYNC(inode)) {
- error = nfs_readpage_from_fscache(ctx, inode, page);
- if (error == 0)
+ ret = nfs_readpage_from_fscache(desc.ctx, inode, page);
+ if (ret == 0)
goto out;
}
- xchg(&ctx->error, 0);
- error = nfs_readpage_async(ctx, inode, page);
- if (!error) {
- error = wait_on_page_locked_killable(page);
- if (!PageUptodate(page) && !error)
- error = xchg(&ctx->error, 0);
- }
-out:
- put_nfs_open_context(ctx);
- return error;
-out_unlock:
- unlock_page(page);
- return error;
-}
-
-struct nfs_readdesc {
- struct nfs_pageio_descriptor *pgio;
- struct nfs_open_context *ctx;
-};
-
-static int
-readpage_async_filler(void *data, struct page *page)
-{
- struct nfs_readdesc *desc = (struct nfs_readdesc *)data;
- struct nfs_page *new;
- unsigned int len;
- int error;
+ xchg(&desc.ctx->error, 0);
+ nfs_pageio_init_read(&desc.pgio, inode, false,
+ &nfs_async_read_completion_ops);
- len = nfs_page_length(page);
- if (len == 0)
- return nfs_return_empty_page(page);
+ ret = readpage_async_filler(&desc, page);
- new = nfs_create_request(desc->ctx, page, 0, len);
- if (IS_ERR(new))
- goto out_error;
+ if (!ret)
+ nfs_pageio_complete_read(&desc.pgio, inode);
- if (len < PAGE_SIZE)
- zero_user_segment(page, len, PAGE_SIZE);
- if (!nfs_pageio_add_request(desc->pgio, new)) {
- nfs_list_remove_request(new);
- error = desc->pgio->pg_error;
- nfs_readpage_release(new, error);
- goto out;
+ ret = desc.pgio.pg_error < 0 ? desc.pgio.pg_error : 0;
+ if (!ret) {
+ ret = wait_on_page_locked_killable(page);
+ if (!PageUptodate(page) && !ret)
+ ret = xchg(&desc.ctx->error, 0);
}
- return 0;
-out_error:
- error = PTR_ERR(new);
- unlock_page(page);
out:
- return error;
+ put_nfs_open_context(desc.ctx);
+ return ret;
+out_unlock:
+ unlock_page(page);
+ return ret;
}
-int nfs_readpages(struct file *filp, struct address_space *mapping,
+int nfs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
- struct nfs_pageio_descriptor pgio;
- struct nfs_pgio_mirror *pgm;
- struct nfs_readdesc desc = {
- .pgio = &pgio,
- };
+ struct nfs_readdesc desc;
struct inode *inode = mapping->host;
- unsigned long npages;
- int ret = -ESTALE;
+ int ret;
dprintk("NFS: nfs_readpages (%s/%Lu %d)\n",
inode->i_sb->s_id,
@@ -422,15 +405,17 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
nr_pages);
nfs_inc_stats(inode, NFSIOS_VFSREADPAGES);
+ ret = -ESTALE;
if (NFS_STALE(inode))
goto out;
- if (filp == NULL) {
+ if (file == NULL) {
+ ret = -EBADF;
desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
if (desc.ctx == NULL)
- return -EBADF;
+ goto out;
} else
- desc.ctx = get_nfs_open_context(nfs_file_open_context(filp));
+ desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
/* attempt to read as many of the pages as possible from the cache
* - this returns -ENOBUFS immediately if the cookie is negative
@@ -440,20 +425,13 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
if (ret == 0)
goto read_complete; /* all pages were read */
- nfs_pageio_init_read(&pgio, inode, false,
+ nfs_pageio_init_read(&desc.pgio, inode, false,
&nfs_async_read_completion_ops);
ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc);
- nfs_pageio_complete(&pgio);
- /* It doesn't make sense to do mirrored reads! */
- WARN_ON_ONCE(pgio.pg_mirror_count != 1);
+ nfs_pageio_complete_read(&desc.pgio, inode);
- pgm = &pgio.pg_mirrors[0];
- NFS_I(inode)->read_io += pgm->pg_bytes_written;
- npages = (pgm->pg_bytes_written + PAGE_SIZE - 1) >>
- PAGE_SHIFT;
- nfs_add_stats(inode, NFSIOS_READPAGES, npages);
read_complete:
put_nfs_open_context(desc.ctx);
out: