diff options
Diffstat (limited to 'net/sunrpc/socklib.c')
-rw-r--r-- | net/sunrpc/socklib.c | 164 |
1 files changed, 59 insertions, 105 deletions
diff --git a/net/sunrpc/socklib.c b/net/sunrpc/socklib.c index 1b2b84feeec6..4e92e2a50168 100644 --- a/net/sunrpc/socklib.c +++ b/net/sunrpc/socklib.c @@ -27,97 +27,60 @@ struct xdr_skb_reader { struct sk_buff *skb; unsigned int offset; + bool need_checksum; size_t count; __wsum csum; }; -typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, - size_t len); - /** * xdr_skb_read_bits - copy some data bits from skb to internal buffer * @desc: sk_buff copy helper * @to: copy destination * @len: number of bytes to copy * - * Possibly called several times to iterate over an sk_buff and copy - * data out of it. + * Possibly called several times to iterate over an sk_buff and copy data out of + * it. */ static size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len) { - if (len > desc->count) - len = desc->count; - if (unlikely(skb_copy_bits(desc->skb, desc->offset, to, len))) - return 0; - desc->count -= len; - desc->offset += len; - return len; -} + len = min(len, desc->count); + + if (desc->need_checksum) { + __wsum csum; + + csum = skb_copy_and_csum_bits(desc->skb, desc->offset, to, len); + desc->csum = csum_block_add(desc->csum, csum, desc->offset); + } else { + if (unlikely(skb_copy_bits(desc->skb, desc->offset, to, len))) + return 0; + } -/** - * xdr_skb_read_and_csum_bits - copy and checksum from skb to buffer - * @desc: sk_buff copy helper - * @to: copy destination - * @len: number of bytes to copy - * - * Same as skb_read_bits, but calculate a checksum at the same time. - */ -static size_t xdr_skb_read_and_csum_bits(struct xdr_skb_reader *desc, void *to, size_t len) -{ - unsigned int pos; - __wsum csum2; - - if (len > desc->count) - len = desc->count; - pos = desc->offset; - csum2 = skb_copy_and_csum_bits(desc->skb, pos, to, len); - desc->csum = csum_block_add(desc->csum, csum2, pos); desc->count -= len; desc->offset += len; return len; } -/** - * xdr_partial_copy_from_skb - copy data out of an skb - * @xdr: target XDR buffer - * @base: starting offset - * @desc: sk_buff copy helper - * @copy_actor: virtual method for copying data - * - */ static ssize_t -xdr_partial_copy_from_skb(struct xdr_buf *xdr, unsigned int base, struct xdr_skb_reader *desc, xdr_skb_read_actor copy_actor) +xdr_partial_copy_from_skb(struct xdr_buf *xdr, struct xdr_skb_reader *desc) { - struct page **ppage = xdr->pages; - unsigned int len, pglen = xdr->page_len; - ssize_t copied = 0; - size_t ret; - - len = xdr->head[0].iov_len; - if (base < len) { - len -= base; - ret = copy_actor(desc, (char *)xdr->head[0].iov_base + base, len); - copied += ret; - if (ret != len || !desc->count) - goto out; - base = 0; - } else - base -= len; - - if (unlikely(pglen == 0)) - goto copy_tail; - if (unlikely(base >= pglen)) { - base -= pglen; - goto copy_tail; - } - if (base || xdr->page_base) { - pglen -= base; - base += xdr->page_base; - ppage += base >> PAGE_SHIFT; - base &= ~PAGE_MASK; - } - do { + struct page **ppage = xdr->pages + (xdr->page_base >> PAGE_SHIFT); + unsigned int poff = xdr->page_base & ~PAGE_MASK; + unsigned int pglen = xdr->page_len; + ssize_t copied = 0; + size_t ret; + + if (xdr->head[0].iov_len == 0) + return 0; + + ret = xdr_skb_read_bits(desc, xdr->head[0].iov_base, + xdr->head[0].iov_len); + if (ret != xdr->head[0].iov_len || !desc->count) + return ret; + copied += ret; + + while (pglen) { + unsigned int len = min(PAGE_SIZE - poff, pglen); char *kaddr; /* ACL likes to be lazy in allocating pages - ACLs @@ -126,36 +89,29 @@ xdr_partial_copy_from_skb(struct xdr_buf *xdr, unsigned int base, struct xdr_skb *ppage = alloc_page(GFP_NOWAIT | __GFP_NOWARN); if (unlikely(*ppage == NULL)) { if (copied == 0) - copied = -ENOMEM; - goto out; + return -ENOMEM; + return copied; } } - len = PAGE_SIZE; kaddr = kmap_atomic(*ppage); - if (base) { - len -= base; - if (pglen < len) - len = pglen; - ret = copy_actor(desc, kaddr + base, len); - base = 0; - } else { - if (pglen < len) - len = pglen; - ret = copy_actor(desc, kaddr, len); - } + ret = xdr_skb_read_bits(desc, kaddr + poff, len); flush_dcache_page(*ppage); kunmap_atomic(kaddr); + copied += ret; if (ret != len || !desc->count) - goto out; + return copied; ppage++; - } while ((pglen -= len) != 0); -copy_tail: - len = xdr->tail[0].iov_len; - if (base < len) - copied += copy_actor(desc, (char *)xdr->tail[0].iov_base + base, len - base); -out: + pglen -= len; + poff = 0; + } + + if (xdr->tail[0].iov_len) { + copied += xdr_skb_read_bits(desc, xdr->tail[0].iov_base, + xdr->tail[0].iov_len); + } + return copied; } @@ -169,17 +125,22 @@ out: */ int csum_partial_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb) { - struct xdr_skb_reader desc; - - desc.skb = skb; - desc.offset = 0; - desc.count = skb->len - desc.offset; + struct xdr_skb_reader desc = { + .skb = skb, + .count = skb->len - desc.offset, + }; - if (skb_csum_unnecessary(skb)) - goto no_checksum; + if (skb_csum_unnecessary(skb)) { + if (xdr_partial_copy_from_skb(xdr, &desc) < 0) + return -1; + if (desc.count) + return -1; + return 0; + } + desc.need_checksum = true; desc.csum = csum_partial(skb->data, desc.offset, skb->csum); - if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_and_csum_bits) < 0) + if (xdr_partial_copy_from_skb(xdr, &desc) < 0) return -1; if (desc.offset != skb->len) { __wsum csum2; @@ -194,14 +155,7 @@ int csum_partial_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb) !skb->csum_complete_sw) netdev_rx_csum_fault(skb->dev, skb); return 0; -no_checksum: - if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0) - return -1; - if (desc.count) - return -1; - return 0; } -EXPORT_SYMBOL_GPL(csum_partial_copy_to_xdr); static inline int xprt_sendmsg(struct socket *sock, struct msghdr *msg, size_t seek) |