Merge tag 'nfs-for-3.6-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Features include:
   - More preparatory patches for modularising NFSv2/v3/v4.  Split out
     the various NFSv2/v3/v4-specific code into separate files
   - More preparation for the NFSv4 migration code
   - Ensure that OPEN(O_CREATE) observes the pNFS mds threshold
     parameters
   - pNFS fast failover when the data servers are down
   - Various cleanups and debugging patches"

* tag 'nfs-for-3.6-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (67 commits)
  nfs: fix fl_type tests in NFSv4 code
  NFS: fix pnfs regression with directio writes
  NFS: fix pnfs regression with directio reads
  sunrpc: clnt: Add missing braces
  nfs: fix stub return type warnings
  NFS: exit_nfs_v4() shouldn't be an __exit function
  SUNRPC: Add a missing spin_unlock to gss_mech_list_pseudoflavors
  NFS: Split out NFS v4 client functions
  NFS: Split out the NFS v4 filesystem types
  NFS: Create a single nfs_clone_super() function
  NFS: Split out NFS v4 server creating code
  NFS: Initialize the NFS v4 client from init_nfs_v4()
  NFS: Move the v4 getroot code to nfs4getroot.c
  NFS: Split out NFS v4 file operations
  NFS: Initialize v4 sysctls from nfs_init_v4()
  NFS: Create an init_nfs_v4() function
  NFS: Split out NFS v4 inode operations
  NFS: Split out NFS v3 inode operations
  NFS: Split out NFS v2 inode operations
  NFS: Clean up nfs4_proc_setclientid() and friends
  ...

1 files changed, 69 insertions, 58 deletions

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 0cf165580d8d..0afba1b4b656 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -129,34 +129,6 @@ xdr_terminate_string(struct xdr_buf *buf, const u32 len)
 EXPORT_SYMBOL_GPL(xdr_terminate_string);
 
 void
-xdr_encode_pages(struct xdr_buf *xdr, struct page **pages, unsigned int base,
-                 unsigned int len)
-{
-        struct kvec *tail = xdr->tail;
-        u32 *p;
-
-        xdr->pages = pages;
-        xdr->page_base = base;
-        xdr->page_len = len;
-
-        p = (u32 *)xdr->head[0].iov_base + XDR_QUADLEN(xdr->head[0].iov_len);
-        tail->iov_base = p;
-        tail->iov_len = 0;
-
-        if (len & 3) {
-                unsigned int pad = 4 - (len & 3);
-
-                *p = 0;
-                tail->iov_base = (char *)p + (len & 3);
-                tail->iov_len  = pad;
-                len += pad;
-        }
-        xdr->buflen += len;
-        xdr->len += len;
-}
-EXPORT_SYMBOL_GPL(xdr_encode_pages);
-
-void
 xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
                  struct page **pages, unsigned int base, unsigned int len)
 {
@@ -457,6 +429,16 @@ xdr_shift_buf(struct xdr_buf *buf, size_t len)
 EXPORT_SYMBOL_GPL(xdr_shift_buf);
 
 /**
+ * xdr_stream_pos - Return the current offset from the start of the xdr_stream
+ * @xdr: pointer to struct xdr_stream
+ */
+unsigned int xdr_stream_pos(const struct xdr_stream *xdr)
+{
+        return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2;
+}
+EXPORT_SYMBOL_GPL(xdr_stream_pos);
+
+/**
  * xdr_init_encode - Initialize a struct xdr_stream for sending data.
  * @xdr: pointer to xdr_stream struct
  * @buf: pointer to XDR buffer in which to encode data
@@ -556,13 +538,11 @@ void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int b
 EXPORT_SYMBOL_GPL(xdr_write_pages);
 
 static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
-                __be32 *p, unsigned int len)
+                unsigned int len)
 {
         if (len > iov->iov_len)
                 len = iov->iov_len;
-        if (p == NULL)
-                p = (__be32*)iov->iov_base;
-        xdr->p = p;
+        xdr->p = (__be32*)iov->iov_base;
         xdr->end = (__be32*)(iov->iov_base + len);
         xdr->iov = iov;
         xdr->page_ptr = NULL;
@@ -609,7 +589,7 @@ static void xdr_set_next_page(struct xdr_stream *xdr)
         newbase -= xdr->buf->page_base;
 
         if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0)
-                xdr_set_iov(xdr, xdr->buf->tail, NULL, xdr->buf->len);
+                xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len);
 }
 
 static bool xdr_set_next_buffer(struct xdr_stream *xdr)
@@ -618,7 +598,7 @@ static bool xdr_set_next_buffer(struct xdr_stream *xdr)
                 xdr_set_next_page(xdr);
         else if (xdr->iov == xdr->buf->head) {
                 if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0)
-                        xdr_set_iov(xdr, xdr->buf->tail, NULL, xdr->buf->len);
+                        xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len);
         }
         return xdr->p != xdr->end;
 }
@@ -634,10 +614,15 @@ void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
         xdr->buf = buf;
         xdr->scratch.iov_base = NULL;
         xdr->scratch.iov_len = 0;
+        xdr->nwords = XDR_QUADLEN(buf->len);
         if (buf->head[0].iov_len != 0)
-                xdr_set_iov(xdr, buf->head, p, buf->len);
+                xdr_set_iov(xdr, buf->head, buf->len);
         else if (buf->page_len != 0)
                 xdr_set_page_base(xdr, 0, buf->len);
+        if (p != NULL && p > xdr->p && xdr->end >= p) {
+                xdr->nwords -= p - xdr->p;
+                xdr->p = p;
+        }
 }
 EXPORT_SYMBOL_GPL(xdr_init_decode);
 
@@ -662,12 +647,14 @@ EXPORT_SYMBOL_GPL(xdr_init_decode_pages);
 
 static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
 {
+        unsigned int nwords = XDR_QUADLEN(nbytes);
         __be32 *p = xdr->p;
-        __be32 *q = p + XDR_QUADLEN(nbytes);
+        __be32 *q = p + nwords;
 
-        if (unlikely(q > xdr->end || q < p))
+        if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p))
                 return NULL;
         xdr->p = q;
+        xdr->nwords -= nwords;
         return p;
 }
 
@@ -734,6 +721,31 @@ __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
 }
 EXPORT_SYMBOL_GPL(xdr_inline_decode);
 
+static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
+{
+        struct xdr_buf *buf = xdr->buf;
+        struct kvec *iov;
+        unsigned int nwords = XDR_QUADLEN(len);
+        unsigned int cur = xdr_stream_pos(xdr);
+
+        if (xdr->nwords == 0)
+                return 0;
+        if (nwords > xdr->nwords) {
+                nwords = xdr->nwords;
+                len = nwords << 2;
+        }
+        /* Realign pages to current pointer position */
+        iov  = buf->head;
+        if (iov->iov_len > cur)
+                xdr_shrink_bufhead(buf, iov->iov_len - cur);
+
+        /* Truncate page data and move it into the tail */
+        if (buf->page_len > len)
+                xdr_shrink_pagelen(buf, buf->page_len - len);
+        xdr->nwords = XDR_QUADLEN(buf->len - cur);
+        return len;
+}
+
 /**
  * xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position
  * @xdr: pointer to xdr_stream struct
@@ -742,39 +754,37 @@ EXPORT_SYMBOL_GPL(xdr_inline_decode);
  * Moves data beyond the current pointer position from the XDR head[] buffer
  * into the page list. Any data that lies beyond current position + "len"
  * bytes is moved into the XDR tail[].
+ *
+ * Returns the number of XDR encoded bytes now contained in the pages
  */
-void xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
+unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 {
         struct xdr_buf *buf = xdr->buf;
         struct kvec *iov;
-        ssize_t shift;
+        unsigned int nwords;
         unsigned int end;
-        int padding;
+        unsigned int padding;
 
-        /* Realign pages to current pointer position */
-        iov  = buf->head;
-        shift = iov->iov_len + (char *)iov->iov_base - (char *)xdr->p;
-        if (shift > 0)
-                xdr_shrink_bufhead(buf, shift);
-
-        /* Truncate page data and move it into the tail */
-        if (buf->page_len > len)
-                xdr_shrink_pagelen(buf, buf->page_len - len);
-        padding = (XDR_QUADLEN(len) << 2) - len;
+        len = xdr_align_pages(xdr, len);
+        if (len == 0)
+                return 0;
+        nwords = XDR_QUADLEN(len);
+        padding = (nwords << 2) - len;
         xdr->iov = iov = buf->tail;
         /* Compute remaining message length.  */
-        end = iov->iov_len;
-        shift = buf->buflen - buf->len;
-        if (shift < end)
-                end -= shift;
-        else if (shift > 0)
-                end = 0;
+        end = ((xdr->nwords - nwords) << 2) + padding;
+        if (end > iov->iov_len)
+                end = iov->iov_len;
+
         /*
          * Position current pointer at beginning of tail, and
          * set remaining message length.
          */
         xdr->p = (__be32 *)((char *)iov->iov_base + padding);
         xdr->end = (__be32 *)((char *)iov->iov_base + end);
+        xdr->page_ptr = NULL;
+        xdr->nwords = XDR_QUADLEN(end - padding);
+        return len;
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
 
@@ -790,12 +800,13 @@ EXPORT_SYMBOL_GPL(xdr_read_pages);
  */
 void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
 {
-        xdr_read_pages(xdr, len);
+        len = xdr_align_pages(xdr, len);
         /*
          * Position current pointer at beginning of tail, and
          * set remaining message length.
          */
-        xdr_set_page_base(xdr, 0, len);
+        if (len != 0)
+                xdr_set_page_base(xdr, 0, len);
 }
 EXPORT_SYMBOL_GPL(xdr_enter_page);