Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck...

[linux-drm-fsl-dcu.git] / fs / nfsd / nfs4xdr.c

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index d9d7fa94967f89beef97614c28f967f21ff7b88a..ee7237f99f54cd413dba6375dbc344084d0ece56 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -141,8 +141,8 @@ xdr_error:                                  \
 
 static void next_decode_page(struct nfsd4_compoundargs *argp)
 {
-       argp->pagelist++;
        argp->p = page_address(argp->pagelist[0]);
+       argp->pagelist++;
        if (argp->pagelen < PAGE_SIZE) {
                argp->end = argp->p + (argp->pagelen>>2);
                argp->pagelen = 0;
@@ -1229,6 +1229,7 @@ nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
                len -= pages * PAGE_SIZE;
 
                argp->p = (__be32 *)page_address(argp->pagelist[0]);
+               argp->pagelist++;
                argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
        }
        argp->p += XDR_QUADLEN(len);
@@ -1597,12 +1598,39 @@ nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
        return true;
 }
 
+/*
+ * Return a rough estimate of the maximum possible reply size.  Note the
+ * estimate includes rpc headers so is meant to be passed to
+ * svc_reserve, not svc_reserve_auth.
+ *
+ * Also note the current compound encoding permits only one operation to
+ * use pages beyond the first one, so the maximum possible length is the
+ * maximum over these values, not the sum.
+ */
+static int nfsd4_max_reply(u32 opnum)
+{
+       switch (opnum) {
+       case OP_READLINK:
+       case OP_READDIR:
+               /*
+                * Both of these ops take a single page for data and put
+                * the head and tail in another page:
+                */
+               return 2 * PAGE_SIZE;
+       case OP_READ:
+               return INT_MAX;
+       default:
+               return PAGE_SIZE;
+       }
+}
+
 static __be32
 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
 {
        DECODE_HEAD;
        struct nfsd4_op *op;
        bool cachethis = false;
+       int max_reply = PAGE_SIZE;
        int i;
 
        READ_BUF(4);
@@ -1652,10 +1680,14 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
                 * op in the compound wants to be cached:
                 */
                cachethis |= nfsd4_cache_this_op(op);
+
+               max_reply = max(max_reply, nfsd4_max_reply(op->opnum));
        }
        /* Sessions make the DRC unnecessary: */
        if (argp->minorversion)
                cachethis = false;
+       if (max_reply != INT_MAX)
+               svc_reserve(argp->rqstp, max_reply);
        argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
 
        DECODE_TAIL;
@@ -2360,7 +2392,7 @@ out_acl:
        if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
                if ((buflen -= 8) < 0)
                        goto out_resource;
-               WRITE64(~(u64)0);
+               WRITE64(exp->ex_path.mnt->mnt_sb->s_maxbytes);
        }
        if (bmval0 & FATTR4_WORD0_MAXLINK) {
                if ((buflen -= 4) < 0)