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authorTrond Myklebust <Trond.Myklebust@netapp.com>2011-01-10 14:48:02 -0500
committerTrond Myklebust <Trond.Myklebust@netapp.com>2011-01-10 14:48:02 -0500
commit68c404b18f6fba404b2753622d0459c68ee128ae (patch)
treec1ec0bb12f19d91071b461cc2831d9d3dd4c74f3 /net/sunrpc
parentd035c36c58dd9183ad6aa7875dea89893faedb55 (diff)
parent6650239a4b01077e80d5a4468562756d77afaa59 (diff)
Merge branch 'bugfixes' into nfs-for-2.6.38
Conflicts: fs/nfs/nfs2xdr.c fs/nfs/nfs3xdr.c fs/nfs/nfs4xdr.c
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/xdr.c155
1 files changed, 124 insertions, 31 deletions
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index cd9e841e7492..679cd674b81d 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -552,6 +552,74 @@ void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int b
552} 552}
553EXPORT_SYMBOL_GPL(xdr_write_pages); 553EXPORT_SYMBOL_GPL(xdr_write_pages);
554 554
555static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
556 __be32 *p, unsigned int len)
557{
558 if (len > iov->iov_len)
559 len = iov->iov_len;
560 if (p == NULL)
561 p = (__be32*)iov->iov_base;
562 xdr->p = p;
563 xdr->end = (__be32*)(iov->iov_base + len);
564 xdr->iov = iov;
565 xdr->page_ptr = NULL;
566}
567
568static int xdr_set_page_base(struct xdr_stream *xdr,
569 unsigned int base, unsigned int len)
570{
571 unsigned int pgnr;
572 unsigned int maxlen;
573 unsigned int pgoff;
574 unsigned int pgend;
575 void *kaddr;
576
577 maxlen = xdr->buf->page_len;
578 if (base >= maxlen)
579 return -EINVAL;
580 maxlen -= base;
581 if (len > maxlen)
582 len = maxlen;
583
584 base += xdr->buf->page_base;
585
586 pgnr = base >> PAGE_SHIFT;
587 xdr->page_ptr = &xdr->buf->pages[pgnr];
588 kaddr = page_address(*xdr->page_ptr);
589
590 pgoff = base & ~PAGE_MASK;
591 xdr->p = (__be32*)(kaddr + pgoff);
592
593 pgend = pgoff + len;
594 if (pgend > PAGE_SIZE)
595 pgend = PAGE_SIZE;
596 xdr->end = (__be32*)(kaddr + pgend);
597 xdr->iov = NULL;
598 return 0;
599}
600
601static void xdr_set_next_page(struct xdr_stream *xdr)
602{
603 unsigned int newbase;
604
605 newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT;
606 newbase -= xdr->buf->page_base;
607
608 if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0)
609 xdr_set_iov(xdr, xdr->buf->tail, NULL, xdr->buf->len);
610}
611
612static bool xdr_set_next_buffer(struct xdr_stream *xdr)
613{
614 if (xdr->page_ptr != NULL)
615 xdr_set_next_page(xdr);
616 else if (xdr->iov == xdr->buf->head) {
617 if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0)
618 xdr_set_iov(xdr, xdr->buf->tail, NULL, xdr->buf->len);
619 }
620 return xdr->p != xdr->end;
621}
622
555/** 623/**
556 * xdr_init_decode - Initialize an xdr_stream for decoding data. 624 * xdr_init_decode - Initialize an xdr_stream for decoding data.
557 * @xdr: pointer to xdr_stream struct 625 * @xdr: pointer to xdr_stream struct
@@ -560,41 +628,67 @@ EXPORT_SYMBOL_GPL(xdr_write_pages);
560 */ 628 */
561void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p) 629void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
562{ 630{
563 struct kvec *iov = buf->head;
564 unsigned int len = iov->iov_len;
565
566 if (len > buf->len)
567 len = buf->len;
568 xdr->buf = buf; 631 xdr->buf = buf;
569 xdr->iov = iov; 632 xdr->scratch.iov_base = NULL;
570 xdr->p = p; 633 xdr->scratch.iov_len = 0;
571 xdr->end = (__be32 *)((char *)iov->iov_base + len); 634 if (buf->head[0].iov_len != 0)
635 xdr_set_iov(xdr, buf->head, p, buf->len);
636 else if (buf->page_len != 0)
637 xdr_set_page_base(xdr, 0, buf->len);
572} 638}
573EXPORT_SYMBOL_GPL(xdr_init_decode); 639EXPORT_SYMBOL_GPL(xdr_init_decode);
574 640
575/** 641static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
576 * xdr_inline_peek - Allow read-ahead in the XDR data stream
577 * @xdr: pointer to xdr_stream struct
578 * @nbytes: number of bytes of data to decode
579 *
580 * Check if the input buffer is long enough to enable us to decode
581 * 'nbytes' more bytes of data starting at the current position.
582 * If so return the current pointer without updating the current
583 * pointer position.
584 */
585__be32 * xdr_inline_peek(struct xdr_stream *xdr, size_t nbytes)
586{ 642{
587 __be32 *p = xdr->p; 643 __be32 *p = xdr->p;
588 __be32 *q = p + XDR_QUADLEN(nbytes); 644 __be32 *q = p + XDR_QUADLEN(nbytes);
589 645
590 if (unlikely(q > xdr->end || q < p)) 646 if (unlikely(q > xdr->end || q < p))
591 return NULL; 647 return NULL;
648 xdr->p = q;
592 return p; 649 return p;
593} 650}
594EXPORT_SYMBOL_GPL(xdr_inline_peek);
595 651
596/** 652/**
597 * xdr_inline_decode - Retrieve non-page XDR data to decode 653 * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
654 * @xdr: pointer to xdr_stream struct
655 * @buf: pointer to an empty buffer
656 * @buflen: size of 'buf'
657 *
658 * The scratch buffer is used when decoding from an array of pages.
659 * If an xdr_inline_decode() call spans across page boundaries, then
660 * we copy the data into the scratch buffer in order to allow linear
661 * access.
662 */
663void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
664{
665 xdr->scratch.iov_base = buf;
666 xdr->scratch.iov_len = buflen;
667}
668EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer);
669
670static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes)
671{
672 __be32 *p;
673 void *cpdest = xdr->scratch.iov_base;
674 size_t cplen = (char *)xdr->end - (char *)xdr->p;
675
676 if (nbytes > xdr->scratch.iov_len)
677 return NULL;
678 memcpy(cpdest, xdr->p, cplen);
679 cpdest += cplen;
680 nbytes -= cplen;
681 if (!xdr_set_next_buffer(xdr))
682 return NULL;
683 p = __xdr_inline_decode(xdr, nbytes);
684 if (p == NULL)
685 return NULL;
686 memcpy(cpdest, p, nbytes);
687 return xdr->scratch.iov_base;
688}
689
690/**
691 * xdr_inline_decode - Retrieve XDR data to decode
598 * @xdr: pointer to xdr_stream struct 692 * @xdr: pointer to xdr_stream struct
599 * @nbytes: number of bytes of data to decode 693 * @nbytes: number of bytes of data to decode
600 * 694 *
@@ -605,13 +699,16 @@ EXPORT_SYMBOL_GPL(xdr_inline_peek);
605 */ 699 */
606__be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) 700__be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
607{ 701{
608 __be32 *p = xdr->p; 702 __be32 *p;
609 __be32 *q = p + XDR_QUADLEN(nbytes);
610 703
611 if (unlikely(q > xdr->end || q < p)) 704 if (nbytes == 0)
705 return xdr->p;
706 if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr))
612 return NULL; 707 return NULL;
613 xdr->p = q; 708 p = __xdr_inline_decode(xdr, nbytes);
614 return p; 709 if (p != NULL)
710 return p;
711 return xdr_copy_to_scratch(xdr, nbytes);
615} 712}
616EXPORT_SYMBOL_GPL(xdr_inline_decode); 713EXPORT_SYMBOL_GPL(xdr_inline_decode);
617 714
@@ -671,16 +768,12 @@ EXPORT_SYMBOL_GPL(xdr_read_pages);
671 */ 768 */
672void xdr_enter_page(struct xdr_stream *xdr, unsigned int len) 769void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
673{ 770{
674 char * kaddr = page_address(xdr->buf->pages[0]);
675 xdr_read_pages(xdr, len); 771 xdr_read_pages(xdr, len);
676 /* 772 /*
677 * Position current pointer at beginning of tail, and 773 * Position current pointer at beginning of tail, and
678 * set remaining message length. 774 * set remaining message length.
679 */ 775 */
680 if (len > PAGE_CACHE_SIZE - xdr->buf->page_base) 776 xdr_set_page_base(xdr, 0, len);
681 len = PAGE_CACHE_SIZE - xdr->buf->page_base;
682 xdr->p = (__be32 *)(kaddr + xdr->buf->page_base);
683 xdr->end = (__be32 *)((char *)xdr->p + len);
684} 777}
685EXPORT_SYMBOL_GPL(xdr_enter_page); 778EXPORT_SYMBOL_GPL(xdr_enter_page);
686 779