NFS: make iocb available everywhere in direct read path

Pass the iocb argument all the way down to the direct read request
scheduler, and make it available in nfs_direct_read_result.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.
Millions of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 12 insertions, 8 deletions

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 6ecde9602f99..6cbddc51acbc 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -68,6 +68,8 @@ static kmem_cache_t *nfs_direct_cachep;
 struct nfs_direct_req {
         struct kref             kref;           /* release manager */
         struct list_head        list;           /* nfs_read_data structs */
+        struct file *           filp;           /* file descriptor */
+        struct kiocb *          iocb;           /* controlling i/o request */
         wait_queue_head_t       wait;           /* wait for i/o completion */
         struct inode *          inode;          /* target file of I/O */
         struct page **          pages;          /* pages in our buffer */
@@ -240,8 +242,12 @@ static const struct rpc_call_ops nfs_read_direct_ops = {
  * For each nfs_read_data struct that was allocated on the list, dispatch
  * an NFS READ operation
  */
-static void nfs_direct_read_schedule(struct nfs_direct_req *dreq, struct inode *inode, struct nfs_open_context *ctx, unsigned long user_addr, size_t count, loff_t file_offset)
+static void nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t file_offset)
 {
+        struct file *file = dreq->filp;
+        struct inode *inode = file->f_mapping->host;
+        struct nfs_open_context *ctx = (struct nfs_open_context *)
+                                                        file->private_data;
         struct list_head *list = &dreq->list;
         struct page **pages = dreq->pages;
         size_t rsize = NFS_SERVER(inode)->rsize;
@@ -321,10 +327,11 @@ static ssize_t nfs_direct_read_wait(struct nfs_direct_req *dreq, int intr)
         return (ssize_t) result;
 }
 
-static ssize_t nfs_direct_read(struct inode *inode, struct nfs_open_context *ctx, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, unsigned int nr_pages)
+static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, unsigned int nr_pages)
 {
         ssize_t result;
         sigset_t oldset;
+        struct inode *inode = iocb->ki_filp->f_mapping->host;
         struct rpc_clnt *clnt = NFS_CLIENT(inode);
         struct nfs_direct_req *dreq;
 
@@ -335,11 +342,11 @@ static ssize_t nfs_direct_read(struct inode *inode, struct nfs_open_context *ctx
         dreq->pages = pages;
         dreq->npages = nr_pages;
         dreq->inode = inode;
+        dreq->filp = iocb->ki_filp;
 
         nfs_add_stats(inode, NFSIOS_DIRECTREADBYTES, count);
         rpc_clnt_sigmask(clnt, &oldset);
-        nfs_direct_read_schedule(dreq, inode, ctx, user_addr, count,
-                                 file_offset);
+        nfs_direct_read_schedule(dreq, user_addr, count, file_offset);
         result = nfs_direct_read_wait(dreq, clnt->cl_intr);
         rpc_clnt_sigunmask(clnt, &oldset);
 
@@ -520,10 +527,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, char __user *buf, size_t count,
         int page_count;
         struct page **pages;
         struct file *file = iocb->ki_filp;
-        struct nfs_open_context *ctx =
-                        (struct nfs_open_context *) file->private_data;
         struct address_space *mapping = file->f_mapping;
-        struct inode *inode = mapping->host;
 
         dprintk("nfs: direct read(%s/%s, %lu@%Ld)\n",
                 file->f_dentry->d_parent->d_name.name,
@@ -553,7 +557,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, char __user *buf, size_t count,
                 goto out;
         }
 
-        retval = nfs_direct_read(inode, ctx, (unsigned long) buf, count, pos,
+        retval = nfs_direct_read(iocb, (unsigned long) buf, count, pos,
                                                 pages, page_count);
         if (retval > 0)
                 iocb->ki_pos = pos + retval;