3 files changed, 47 insertions, 26 deletions

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 0a3d2ce89660..5d8ce79385ed 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -737,10 +737,14 @@ retry:
 
         while (!done && index <= end) {
                 struct ceph_osd_req_op ops[2];
+                int num_ops = do_sync ? 2 : 1;
+                struct ceph_vino vino;
                 unsigned i;
                 int first;
                 pgoff_t next;
                 int pvec_pages, locked_pages;
+                struct page **pages = NULL;
+                mempool_t *pool = NULL; /* Becomes non-null if mempool used */
                 struct page *page;
                 int want;
                 u64 offset, len;
@@ -824,16 +828,19 @@ get_more_pages:
                                 break;
                         }
 
-                        /* ok */
+                        /*
+                         * We have something to write.  If this is
+                         * the first locked page this time through,
+                         * allocate an osd request and a page array
+                         * that it will use.
+                         */
                         if (locked_pages == 0) {
-                                struct ceph_vino vino;
-                                int num_ops = do_sync ? 2 : 1;
                                 size_t size;
-                                struct page **pages;
-                                mempool_t *pool = NULL;
+
+                                BUG_ON(pages);
 
                                 /* prepare async write request */
-                                offset = (u64) page_offset(page);
+                                offset = (u64)page_offset(page);
                                 len = wsize;
                                 req = ceph_writepages_osd_request(inode,
                                                         offset, &len, snapc,
@@ -845,11 +852,6 @@ get_more_pages:
                                         break;
                                 }
 
-                                vino = ceph_vino(inode);
-                                ceph_osdc_build_request(req, offset,
-                                        num_ops, ops, snapc, vino.snap,
-                                        &inode->i_mtime);
-
                                 req->r_callback = writepages_finish;
                                 req->r_inode = inode;
 
@@ -858,16 +860,9 @@ get_more_pages:
                                 pages = kmalloc(size, GFP_NOFS);
                                 if (!pages) {
                                         pool = fsc->wb_pagevec_pool;
-
                                         pages = mempool_alloc(pool, GFP_NOFS);
-                                        WARN_ON(!pages);
+                                        BUG_ON(!pages);
                                 }
-
-                                req->r_data_out.pages = pages;
-                                req->r_data_out.pages_from_pool = !!pool;
-                                req->r_data_out.type = CEPH_OSD_DATA_TYPE_PAGES;
-                                req->r_data_out.length = len;
-                                req->r_data_out.alignment = 0;
                         }
 
                         /* note position of first page in pvec */
@@ -885,7 +880,7 @@ get_more_pages:
                         }
 
                         set_page_writeback(page);
-                        req->r_data_out.pages[locked_pages] = page;
+                        pages[locked_pages] = page;
                         locked_pages++;
                         next = page->index + 1;
                 }
@@ -914,18 +909,30 @@ get_more_pages:
                         pvec.nr -= i-first;
                 }
 
-                /* submit the write */
-                offset = page_offset(req->r_data_out.pages[0]);
+                /* Format the osd request message and submit the write */
+
+                offset = page_offset(pages[0]);
                 len = min((snap_size ? snap_size : i_size_read(inode)) - offset,
                           (u64)locked_pages << PAGE_CACHE_SHIFT);
                 dout("writepages got %d pages at %llu~%llu\n",
                      locked_pages, offset, len);
 
-                /* revise final length, page count */
+                req->r_data_out.type = CEPH_OSD_DATA_TYPE_PAGES;
+                req->r_data_out.pages = pages;
                 req->r_data_out.length = len;
-                req->r_request_ops[0].extent.length = cpu_to_le64(len);
-                req->r_request_ops[0].payload_len = cpu_to_le32(len);
-                req->r_request->hdr.data_len = cpu_to_le32(len);
+                req->r_data_out.alignment = 0;
+                req->r_data_out.pages_from_pool = !!pool;
+
+                pages = NULL;   /* request message now owns the pages array */
+                pool = NULL;
+
+                /* Update the write op length in case we changed it */
+
+                osd_req_op_extent_update(&ops[0], len);
+
+                vino = ceph_vino(inode);
+                ceph_osdc_build_request(req, offset, num_ops, ops,
+                                        snapc, vino.snap, &inode->i_mtime);
 
                 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
                 BUG_ON(rc);
diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index ffaf9076fdc4..5ee1a3776b4b 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -234,6 +234,7 @@ extern void osd_req_op_init(struct ceph_osd_req_op *op, u16 opcode);
 extern void osd_req_op_extent_init(struct ceph_osd_req_op *op, u16 opcode,
                                         u64 offset, u64 length,
                                         u64 truncate_size, u32 truncate_seq);
+extern void osd_req_op_extent_update(struct ceph_osd_req_op *op, u64 length);
 extern void osd_req_op_cls_init(struct ceph_osd_req_op *op, u16 opcode,
                                         const char *class, const char *method,
                                         const void *request_data,
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 9ca693d0df19..426ca1f2a721 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -296,6 +296,19 @@ void osd_req_op_extent_init(struct ceph_osd_req_op *op, u16 opcode,
 }
 EXPORT_SYMBOL(osd_req_op_extent_init);
 
+void osd_req_op_extent_update(struct ceph_osd_req_op *op, u64 length)
+{
+        u64 previous = op->extent.length;
+
+        if (length == previous)
+                return;         /* Nothing to do */
+        BUG_ON(length > previous);
+
+        op->extent.length = length;
+        op->payload_len -= previous - length;
+}
+EXPORT_SYMBOL(osd_req_op_extent_update);
+
 void osd_req_op_cls_init(struct ceph_osd_req_op *op, u16 opcode,
                         const char *class, const char *method,
                         const void *request_data, size_t request_data_size)