NFS: Clean up: split out the RPC transmission from nfs_pagein_multi/one

...and do the same for nfs_flush_multi/one.

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

2 files changed, 102 insertions, 83 deletions

diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 581534a4aed7..0215bac35fc6 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -30,8 +30,6 @@
 
 #define NFSDBG_FACILITY         NFSDBG_PAGECACHE
 
-static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc);
-static int nfs_pagein_one(struct nfs_pageio_descriptor *desc);
 static const struct nfs_pageio_ops nfs_pageio_read_ops;
 static const struct rpc_call_ops nfs_read_partial_ops;
 static const struct rpc_call_ops nfs_read_full_ops;
@@ -253,6 +251,27 @@ static int nfs_do_read(struct nfs_read_data *data,
         return nfs_initiate_read(data, NFS_CLIENT(inode), call_ops);
 }
 
+static int
+nfs_do_multiple_reads(struct list_head *head,
+                const struct rpc_call_ops *call_ops,
+                struct pnfs_layout_segment *lseg)
+{
+        struct nfs_read_data *data;
+        int ret = 0;
+
+        while (!list_empty(head)) {
+                int ret2;
+
+                data = list_entry(head->next, struct nfs_read_data, list);
+                list_del_init(&data->list);
+
+                ret2 = nfs_do_read(data, call_ops, lseg);
+                if (ret == 0)
+                        ret = ret2;
+        }
+        return ret;
+}
+
 static void
 nfs_async_read_error(struct list_head *head)
 {
@@ -279,7 +298,7 @@ nfs_async_read_error(struct list_head *head)
  * won't see the new data until our attribute cache is updated.  This is more
  * or less conventional NFS client behavior.
  */
-static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc)
+static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
         struct nfs_page *req = nfs_list_entry(desc->pg_list.next);
         struct page *page = req->wb_page;
@@ -288,11 +307,10 @@ static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc)
         unsigned int offset;
         int requests = 0;
         int ret = 0;
-        struct pnfs_layout_segment *lseg = desc->pg_lseg;
-        LIST_HEAD(list);
 
         nfs_list_remove_request(req);
 
+        offset = 0;
         nbytes = desc->pg_count;
         do {
                 size_t len = min(nbytes,rsize);
@@ -300,57 +318,33 @@ static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc)
                 data = nfs_readdata_alloc(1);
                 if (!data)
                         goto out_bad;
-                list_add(&data->list, &list);
+                data->pagevec[0] = page;
+                nfs_read_rpcsetup(req, data, len, offset);
+                list_add(&data->list, res);
                 requests++;
                 nbytes -= len;
+                offset += len;
         } while(nbytes != 0);
         atomic_set(&req->wb_complete, requests);
-
         ClearPageError(page);
-        offset = 0;
-        nbytes = desc->pg_count;
-        do {
-                int ret2;
-
-                data = list_entry(list.next, struct nfs_read_data, list);
-                list_del_init(&data->list);
-
-                data->pagevec[0] = page;
-
-                if (nbytes < rsize)
-                        rsize = nbytes;
-                nfs_read_rpcsetup(req, data, rsize, offset);
-                ret2 = nfs_do_read(data, &nfs_read_partial_ops, lseg);
-                if (ret == 0)
-                        ret = ret2;
-                offset += rsize;
-                nbytes -= rsize;
-        } while (nbytes != 0);
-        put_lseg(lseg);
-        desc->pg_lseg = NULL;
-
         return ret;
-
 out_bad:
-        while (!list_empty(&list)) {
-                data = list_entry(list.next, struct nfs_read_data, list);
+        while (!list_empty(res)) {
+                data = list_entry(res->next, struct nfs_read_data, list);
                 list_del(&data->list);
                 nfs_readdata_free(data);
         }
         SetPageError(page);
         nfs_readpage_release(req);
-        put_lseg(lseg);
-        desc->pg_lseg = NULL;
         return -ENOMEM;
 }
 
-static int nfs_pagein_one(struct nfs_pageio_descriptor *desc)
+static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
         struct nfs_page         *req;
         struct page             **pages;
         struct nfs_read_data    *data;
         struct list_head *head = &desc->pg_list;
-        struct pnfs_layout_segment *lseg = desc->pg_lseg;
         int ret = 0;
 
         data = nfs_readdata_alloc(nfs_page_array_len(desc->pg_base,
@@ -372,18 +366,32 @@ static int nfs_pagein_one(struct nfs_pageio_descriptor *desc)
         req = nfs_list_entry(data->pages.next);
 
         nfs_read_rpcsetup(req, data, desc->pg_count, 0);
-        ret = nfs_do_read(data, &nfs_read_full_ops, lseg);
+        list_add(&data->list, res);
 out:
-        put_lseg(lseg);
-        desc->pg_lseg = NULL;
         return ret;
 }
 
 int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
 {
-        if (desc->pg_bsize < PAGE_CACHE_SIZE)
-                return nfs_pagein_multi(desc);
-        return nfs_pagein_one(desc);
+        LIST_HEAD(head);
+        int ret;
+
+        if (desc->pg_bsize < PAGE_CACHE_SIZE) {
+                ret = nfs_pagein_multi(desc, &head);
+                if (ret == 0)
+                        ret = nfs_do_multiple_reads(&head,
+                                        &nfs_read_partial_ops,
+                                        desc->pg_lseg);
+        } else {
+                ret = nfs_pagein_one(desc, &head);
+                if (ret == 0)
+                        ret = nfs_do_multiple_reads(&head,
+                                        &nfs_read_full_ops,
+                                        desc->pg_lseg);
+        }
+        put_lseg(desc->pg_lseg);
+        desc->pg_lseg = NULL;
+        return ret;
 }
 EXPORT_SYMBOL_GPL(nfs_generic_pg_readpages);
 
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index d9dd744588d4..bd4b34e5870b 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -903,6 +903,27 @@ static int nfs_do_write(struct nfs_write_data *data,
         return nfs_initiate_write(data, NFS_CLIENT(inode), call_ops, how);
 }
 
+static int nfs_do_multiple_writes(struct list_head *head,
+                const struct rpc_call_ops *call_ops,
+                struct pnfs_layout_segment *lseg,
+                int how)
+{
+        struct nfs_write_data *data;
+        int ret = 0;
+
+        while (!list_empty(head)) {
+                int ret2;
+
+                data = list_entry(head->next, struct nfs_write_data, list);
+                list_del_init(&data->list);
+                
+                ret2 = nfs_do_write(data, call_ops, lseg, how);
+                 if (ret == 0)
+                         ret = ret2;
+        }
+        return ret;
+}
+
 /* If a nfs_flush_* function fails, it should remove reqs from @head and
  * call this on each, which will prepare them to be retried on next
  * writeback using standard nfs.
@@ -920,7 +941,7 @@ static void nfs_redirty_request(struct nfs_page *req)
  * Generate multiple small requests to write out a single
  * contiguous dirty area on one page.
  */
-static int nfs_flush_multi(struct nfs_pageio_descriptor *desc)
+static int nfs_flush_multi(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
         struct nfs_page *req = nfs_list_entry(desc->pg_list.next);
         struct page *page = req->wb_page;
@@ -929,8 +950,6 @@ static int nfs_flush_multi(struct nfs_pageio_descriptor *desc)
         unsigned int offset;
         int requests = 0;
         int ret = 0;
-        struct pnfs_layout_segment *lseg = desc->pg_lseg;
-        LIST_HEAD(list);
 
         nfs_list_remove_request(req);
 
@@ -940,6 +959,7 @@ static int nfs_flush_multi(struct nfs_pageio_descriptor *desc)
                 desc->pg_ioflags &= ~FLUSH_COND_STABLE;
 
 
+        offset = 0;
         nbytes = desc->pg_count;
         do {
                 size_t len = min(nbytes, wsize);
@@ -947,47 +967,23 @@ static int nfs_flush_multi(struct nfs_pageio_descriptor *desc)
                 data = nfs_writedata_alloc(1);
                 if (!data)
                         goto out_bad;
-                list_add(&data->list, &list);
+                data->pagevec[0] = page;
+                nfs_write_rpcsetup(req, data, wsize, offset, desc->pg_ioflags);
+                list_add(&data->list, res);
                 requests++;
                 nbytes -= len;
+                offset += len;
         } while (nbytes != 0);
         atomic_set(&req->wb_complete, requests);
-
-        ClearPageError(page);
-        offset = 0;
-        nbytes = desc->pg_count;
-        do {
-                int ret2;
-
-                data = list_entry(list.next, struct nfs_write_data, list);
-                list_del_init(&data->list);
-
-                data->pagevec[0] = page;
-
-                if (nbytes < wsize)
-                        wsize = nbytes;
-                nfs_write_rpcsetup(req, data, wsize, offset, desc->pg_ioflags);
-                ret2 = nfs_do_write(data, &nfs_write_partial_ops, lseg,
-                                desc->pg_ioflags);
-                if (ret == 0)
-                        ret = ret2;
-                offset += wsize;
-                nbytes -= wsize;
-        } while (nbytes != 0);
-
-        put_lseg(lseg);
-        desc->pg_lseg = NULL;
         return ret;
 
 out_bad:
-        while (!list_empty(&list)) {
-                data = list_entry(list.next, struct nfs_write_data, list);
+        while (!list_empty(res)) {
+                data = list_entry(res->next, struct nfs_write_data, list);
                 list_del(&data->list);
                 nfs_writedata_free(data);
         }
         nfs_redirty_request(req);
-        put_lseg(lseg);
-        desc->pg_lseg = NULL;
         return -ENOMEM;
 }
 
@@ -999,13 +995,12 @@ out_bad:
  * This is the case if nfs_updatepage detects a conflicting request
  * that has been written but not committed.
  */
-static int nfs_flush_one(struct nfs_pageio_descriptor *desc)
+static int nfs_flush_one(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
         struct nfs_page         *req;
         struct page             **pages;
         struct nfs_write_data   *data;
         struct list_head *head = &desc->pg_list;
-        struct pnfs_layout_segment *lseg = desc->pg_lseg;
         int ret = 0;
 
         data = nfs_writedata_alloc(nfs_page_array_len(desc->pg_base,
@@ -1035,18 +1030,34 @@ static int nfs_flush_one(struct nfs_pageio_descriptor *desc)
 
         /* Set up the argument struct */
         nfs_write_rpcsetup(req, data, desc->pg_count, 0, desc->pg_ioflags);
-        ret = nfs_do_write(data, &nfs_write_full_ops, lseg, desc->pg_ioflags);
+        list_add(&data->list, res);
 out:
-        put_lseg(lseg); /* Cleans any gotten in ->pg_test */
-        desc->pg_lseg = NULL;
         return ret;
 }
 
 int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
 {
-        if (desc->pg_bsize < PAGE_CACHE_SIZE)
-                return nfs_flush_multi(desc);
-        return nfs_flush_one(desc);
+        LIST_HEAD(head);
+        int ret;
+
+        if (desc->pg_bsize < PAGE_CACHE_SIZE) {
+                ret = nfs_flush_multi(desc, &head);
+                if (ret == 0)
+                        ret = nfs_do_multiple_writes(&head,
+                                        &nfs_write_partial_ops,
+                                        desc->pg_lseg,
+                                        desc->pg_ioflags);
+        } else {
+                ret = nfs_flush_one(desc, &head);
+                if (ret == 0)
+                        ret = nfs_do_multiple_writes(&head,
+                                        &nfs_write_full_ops,
+                                        desc->pg_lseg,
+                                        desc->pg_ioflags);
+        }
+        put_lseg(desc->pg_lseg);
+        desc->pg_lseg = NULL;
+        return ret;
 }
 EXPORT_SYMBOL_GPL(nfs_generic_pg_writepages);