1 files changed, 84 insertions, 95 deletions

diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 244a8c45b68e..a9c26521a9e2 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -30,6 +30,7 @@
 
 #include <asm/system.h>
 
+#include "internal.h"
 #include "iostat.h"
 
 #define NFSDBG_FACILITY         NFSDBG_PAGECACHE
@@ -65,32 +66,22 @@ struct nfs_read_data *nfs_readdata_alloc(size_t len)
         return p;
 }
 
-static void nfs_readdata_free(struct nfs_read_data *p)
+static void nfs_readdata_rcu_free(struct rcu_head *head)
 {
+        struct nfs_read_data *p = container_of(head, struct nfs_read_data, task.u.tk_rcu);
         if (p && (p->pagevec != &p->page_array[0]))
                 kfree(p->pagevec);
         mempool_free(p, nfs_rdata_mempool);
 }
 
-void nfs_readdata_release(void *data)
+static void nfs_readdata_free(struct nfs_read_data *rdata)
 {
-        nfs_readdata_free(data);
+        call_rcu_bh(&rdata->task.u.tk_rcu, nfs_readdata_rcu_free);
 }
 
-static
-unsigned int nfs_page_length(struct inode *inode, struct page *page)
+void nfs_readdata_release(void *data)
 {
-        loff_t i_size = i_size_read(inode);
-        unsigned long idx;
-
-        if (i_size <= 0)
-                return 0;
-        idx = (i_size - 1) >> PAGE_CACHE_SHIFT;
-        if (page->index > idx)
-                return 0;
-        if (page->index != idx)
-                return PAGE_CACHE_SIZE;
-        return 1 + ((i_size - 1) & (PAGE_CACHE_SIZE - 1));
+        nfs_readdata_free(data);
 }
 
 static
@@ -139,12 +130,12 @@ static int nfs_readpage_sync(struct nfs_open_context *ctx, struct inode *inode,
 {
         unsigned int    rsize = NFS_SERVER(inode)->rsize;
         unsigned int    count = PAGE_CACHE_SIZE;
-        int             result;
+        int result = -ENOMEM;
         struct nfs_read_data *rdata;
 
         rdata = nfs_readdata_alloc(count);
         if (!rdata)
-                return -ENOMEM;
+                goto out_unlock;
 
         memset(rdata, 0, sizeof(*rdata));
         rdata->flags = (IS_SWAPFILE(inode)? NFS_RPC_SWAPFLAGS : 0);
@@ -212,8 +203,9 @@ static int nfs_readpage_sync(struct nfs_open_context *ctx, struct inode *inode,
         result = 0;
 
 io_error:
-        unlock_page(page);
         nfs_readdata_free(rdata);
+out_unlock:
+        unlock_page(page);
         return result;
 }
 
@@ -224,7 +216,7 @@ static int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode,
         struct nfs_page *new;
         unsigned int len;
 
-        len = nfs_page_length(inode, page);
+        len = nfs_page_length(page);
         if (len == 0)
                 return nfs_return_empty_page(page);
         new = nfs_create_request(ctx, inode, page, 0, len);
@@ -316,9 +308,7 @@ static void nfs_execute_read(struct nfs_read_data *data)
         sigset_t oldset;
 
         rpc_clnt_sigmask(clnt, &oldset);
-        lock_kernel();
         rpc_execute(&data->task);
-        unlock_kernel();
         rpc_clnt_sigunmask(clnt, &oldset);
 }
 
@@ -455,6 +445,55 @@ nfs_pagein_list(struct list_head *head, int rpages)
 }
 
 /*
+ * This is the callback from RPC telling us whether a reply was
+ * received or some error occurred (timeout or socket shutdown).
+ */
+int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data)
+{
+        int status;
+
+        dprintk("%s: %4d, (status %d)\n", __FUNCTION__, task->tk_pid,
+                        task->tk_status);
+
+        status = NFS_PROTO(data->inode)->read_done(task, data);
+        if (status != 0)
+                return status;
+
+        nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, data->res.count);
+
+        if (task->tk_status == -ESTALE) {
+                set_bit(NFS_INO_STALE, &NFS_FLAGS(data->inode));
+                nfs_mark_for_revalidate(data->inode);
+        }
+        spin_lock(&data->inode->i_lock);
+        NFS_I(data->inode)->cache_validity |= NFS_INO_INVALID_ATIME;
+        spin_unlock(&data->inode->i_lock);
+        return 0;
+}
+
+static int nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data)
+{
+        struct nfs_readargs *argp = &data->args;
+        struct nfs_readres *resp = &data->res;
+
+        if (resp->eof || resp->count == argp->count)
+                return 0;
+
+        /* This is a short read! */
+        nfs_inc_stats(data->inode, NFSIOS_SHORTREAD);
+        /* Has the server at least made some progress? */
+        if (resp->count == 0)
+                return 0;
+
+        /* Yes, so retry the read at the end of the data */
+        argp->offset += resp->count;
+        argp->pgbase += resp->count;
+        argp->count -= resp->count;
+        rpc_restart_call(task);
+        return -EAGAIN;
+}
+
+/*
  * Handle a read reply that fills part of a page.
  */
 static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata)
@@ -463,12 +502,16 @@ 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 (likely(task->tk_status >= 0)) {
+                nfs_readpage_truncate_uninitialised_page(data);
+                if (nfs_readpage_retry(task, data) != 0)
+                        return;
+        }
+        if (unlikely(task->tk_status < 0))
+                SetPageError(page);
         if (atomic_dec_and_test(&req->wb_complete)) {
                 if (!PageError(page))
                         SetPageUptodate(page);
@@ -496,25 +539,13 @@ static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data)
         count += base;
         for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++)
                 SetPageUptodate(*pages);
-        if (count != 0)
+        if (count == 0)
+                return;
+        /* Was this a short read? */
+        if (data->res.eof || data->res.count == data->args.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);
-        if (count != 0)
-                SetPageError(*pages);
-}
-
 /*
  * This is the callback from RPC telling us whether a reply was
  * received or some error occurred (timeout or socket shutdown).
@@ -523,19 +554,20 @@ static void nfs_readpage_result_full(struct rpc_task *task, void *calldata)
 {
         struct nfs_read_data *data = calldata;
 
+        if (nfs_readpage_result(task, data) != 0)
+                return;
         /*
-         * Note: nfs_readpage_result may change the values of
+         * Note: nfs_readpage_retry 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.
+         * to ensure that we call nfs_readpage_set_pages_uptodate()
+         * first.
          */
         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;
+                if (nfs_readpage_retry(task, data) != 0)
+                        return;
+        }
         while (!list_empty(&data->pages)) {
                 struct nfs_page *req = nfs_list_entry(data->pages.next);
 
@@ -550,50 +582,6 @@ static const struct rpc_call_ops nfs_read_full_ops = {
 };
 
 /*
- * This is the callback from RPC telling us whether a reply was
- * received or some error occurred (timeout or socket shutdown).
- */
-int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data)
-{
-        struct nfs_readargs *argp = &data->args;
-        struct nfs_readres *resp = &data->res;
-        int status;
-
-        dprintk("NFS: %4d nfs_readpage_result, (status %d)\n",
-                task->tk_pid, task->tk_status);
-
-        status = NFS_PROTO(data->inode)->read_done(task, data);
-        if (status != 0)
-                return status;
-
-        nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, resp->count);
-
-        if (task->tk_status < 0) {
-                if (task->tk_status == -ESTALE) {
-                        set_bit(NFS_INO_STALE, &NFS_FLAGS(data->inode));
-                        nfs_mark_for_revalidate(data->inode);
-                }
-        } else if (resp->count < argp->count && !resp->eof) {
-                /* This is a short read! */
-                nfs_inc_stats(data->inode, NFSIOS_SHORTREAD);
-                /* Has the server at least made some progress? */
-                if (resp->count != 0) {
-                        /* Yes, so retry the read at the end of the data */
-                        argp->offset += resp->count;
-                        argp->pgbase += resp->count;
-                        argp->count -= resp->count;
-                        rpc_restart_call(task);
-                        return -EAGAIN;
-                }
-                task->tk_status = -EIO;
-        }
-        spin_lock(&data->inode->i_lock);
-        NFS_I(data->inode)->cache_validity |= NFS_INO_INVALID_ATIME;
-        spin_unlock(&data->inode->i_lock);
-        return 0;
-}
-
-/*
  * Read a page over NFS.
  * We read the page synchronously in the following case:
  *  -   The error flag is set for this page. This happens only when a
@@ -626,9 +614,10 @@ int nfs_readpage(struct file *file, struct page *page)
                 goto out_error;
 
         if (file == NULL) {
+                error = -EBADF;
                 ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
                 if (ctx == NULL)
-                        return -EBADF;
+                        goto out_error;
         } else
                 ctx = get_nfs_open_context((struct nfs_open_context *)
                                 file->private_data);
@@ -663,7 +652,7 @@ readpage_async_filler(void *data, struct page *page)
         unsigned int len;
 
         nfs_wb_page(inode, page);
-        len = nfs_page_length(inode, page);
+        len = nfs_page_length(page);
         if (len == 0)
                 return nfs_return_empty_page(page);
         new = nfs_create_request(desc->ctx, inode, page, 0, len);