nfs/blocklayout: make sure making a aligned read request

Only treat write goes up to the inode size as aligned request,
because it always write PAGE_CACHE_SIZE, but read a dynamic size.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index ddd0138f410c8af4963575b4765d2a3f069c21de..8bc870e4c4670738747ffb2fd5f24b669f30e95a 100644 (file)
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -743,7 +743,7 @@ bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
 
 static bool
 is_aligned_req(struct nfs_pageio_descriptor *pgio,
-               struct nfs_page *req, unsigned int alignment)
+               struct nfs_page *req, unsigned int alignment, bool is_write)
 {
        /*
         * Always accept buffered writes, higher layers take care of the
@@ -758,7 +758,8 @@ is_aligned_req(struct nfs_pageio_descriptor *pgio,
        if (IS_ALIGNED(req->wb_bytes, alignment))
                return true;
 
-       if (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode)) {
+       if (is_write &&
+           (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode))) {
                /*
                 * If the write goes up to the inode size, just write
                 * the full page.  Data past the inode size is
@@ -775,7 +776,7 @@ is_aligned_req(struct nfs_pageio_descriptor *pgio,
 static void
 bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 {
-       if (!is_aligned_req(pgio, req, SECTOR_SIZE)) {
+       if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) {
                nfs_pageio_reset_read_mds(pgio);
                return;
        }
@@ -791,7 +792,7 @@ static size_t
 bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
                struct nfs_page *req)
 {
-       if (!is_aligned_req(pgio, req, SECTOR_SIZE))
+       if (!is_aligned_req(pgio, req, SECTOR_SIZE, false))
                return 0;
        return pnfs_generic_pg_test(pgio, prev, req);
 }
@@ -824,7 +825,7 @@ bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 {
        u64 wb_size;
 
-       if (!is_aligned_req(pgio, req, PAGE_SIZE)) {
+       if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) {
                nfs_pageio_reset_write_mds(pgio);
                return;
        }
@@ -846,7 +847,7 @@ static size_t
 bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
                 struct nfs_page *req)
 {
-       if (!is_aligned_req(pgio, req, PAGE_SIZE))
+       if (!is_aligned_req(pgio, req, PAGE_SIZE, true))
                return 0;
        return pnfs_generic_pg_test(pgio, prev, req);
 }