Cleanup XDR parsing for LAYOUTGET, GETDEVICEINFO

changes LAYOUTGET and GETDEVICEINFO XDR parsing to:
 - not use vmap, which doesn't work on incoherent archs
 - use xdr_stream parsing for all xdr

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 44 insertions, 9 deletions

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index ffb54a082f3a..6f8192f4cfc7 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -502,12 +502,33 @@ filelayout_decode_layout(struct pnfs_layout_hdr *flo,
                          struct nfs4_layoutget_res *lgr,
                          struct nfs4_deviceid *id)
 {
-        uint32_t *p = (uint32_t *)lgr->layout.buf;
+        struct xdr_stream stream;
+        struct xdr_buf buf = {
+                .pages =  lgr->layoutp->pages,
+                .page_len =  lgr->layoutp->len,
+                .buflen =  lgr->layoutp->len,
+                .len = lgr->layoutp->len,
+        };
+        struct page *scratch;
+        __be32 *p;
         uint32_t nfl_util;
         int i;
 
         dprintk("%s: set_layout_map Begin\n", __func__);
 
+        scratch = alloc_page(GFP_KERNEL);
+        if (!scratch)
+                return -ENOMEM;
+
+        xdr_init_decode(&stream, &buf, NULL);
+        xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+
+        /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
+         * num_fh (4) */
+        p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
+        if (unlikely(!p))
+                goto out_err;
+
         memcpy(id, p, sizeof(*id));
         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
         print_deviceid(id);
@@ -529,32 +550,46 @@ filelayout_decode_layout(struct pnfs_layout_hdr *flo,
                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
                 fl->pattern_offset);
 
+        if (!fl->num_fh)
+                goto out_err;
+
         fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
                                GFP_KERNEL);
         if (!fl->fh_array)
-                return -ENOMEM;
+                goto out_err;
 
         for (i = 0; i < fl->num_fh; i++) {
                 /* Do we want to use a mempool here? */
                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), GFP_KERNEL);
-                if (!fl->fh_array[i]) {
-                        filelayout_free_fh_array(fl);
-                        return -ENOMEM;
-                }
+                if (!fl->fh_array[i])
+                        goto out_err_free;
+
+                p = xdr_inline_decode(&stream, 4);
+                if (unlikely(!p))
+                        goto out_err_free;
                 fl->fh_array[i]->size = be32_to_cpup(p++);
                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
                         printk(KERN_ERR "Too big fh %d received %d\n",
                                i, fl->fh_array[i]->size);
-                        filelayout_free_fh_array(fl);
-                        return -EIO;
+                        goto out_err_free;
                 }
+
+                p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
+                if (unlikely(!p))
+                        goto out_err_free;
                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
-                p += XDR_QUADLEN(fl->fh_array[i]->size);
                 dprintk("DEBUG: %s: fh len %d\n", __func__,
                         fl->fh_array[i]->size);
         }
 
+        __free_page(scratch);
         return 0;
+
+out_err_free:
+        filelayout_free_fh_array(fl);
+out_err:
+        __free_page(scratch);
+        return -EIO;
 }
 
 static void