diff options
Diffstat (limited to 'net/rds/message.c')
| -rw-r--r-- | net/rds/message.c | 132 |
1 files changed, 128 insertions, 4 deletions
diff --git a/net/rds/message.c b/net/rds/message.c index 4318cc9b78f7..651834513481 100644 --- a/net/rds/message.c +++ b/net/rds/message.c @@ -33,6 +33,9 @@ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/export.h> +#include <linux/skbuff.h> +#include <linux/list.h> +#include <linux/errqueue.h> #include "rds.h" @@ -53,20 +56,92 @@ void rds_message_addref(struct rds_message *rm) } EXPORT_SYMBOL_GPL(rds_message_addref); +static inline bool skb_zcookie_add(struct sk_buff *skb, u32 cookie) +{ + struct sock_exterr_skb *serr = SKB_EXT_ERR(skb); + int ncookies; + u32 *ptr; + + if (serr->ee.ee_origin != SO_EE_ORIGIN_ZCOOKIE) + return false; + ncookies = serr->ee.ee_data; + if (ncookies == SO_EE_ORIGIN_MAX_ZCOOKIES) + return false; + ptr = skb_put(skb, sizeof(u32)); + *ptr = cookie; + serr->ee.ee_data = ++ncookies; + return true; +} + +static void rds_rm_zerocopy_callback(struct rds_sock *rs, + struct rds_znotifier *znotif) +{ + struct sock *sk = rds_rs_to_sk(rs); + struct sk_buff *skb, *tail; + struct sock_exterr_skb *serr; + unsigned long flags; + struct sk_buff_head *q; + u32 cookie = znotif->z_cookie; + + q = &sk->sk_error_queue; + spin_lock_irqsave(&q->lock, flags); + tail = skb_peek_tail(q); + + if (tail && skb_zcookie_add(tail, cookie)) { + spin_unlock_irqrestore(&q->lock, flags); + mm_unaccount_pinned_pages(&znotif->z_mmp); + consume_skb(rds_skb_from_znotifier(znotif)); + sk->sk_error_report(sk); + return; + } + + skb = rds_skb_from_znotifier(znotif); + serr = SKB_EXT_ERR(skb); + memset(&serr->ee, 0, sizeof(serr->ee)); + serr->ee.ee_errno = 0; + serr->ee.ee_origin = SO_EE_ORIGIN_ZCOOKIE; + serr->ee.ee_info = 0; + WARN_ON(!skb_zcookie_add(skb, cookie)); + + __skb_queue_tail(q, skb); + + spin_unlock_irqrestore(&q->lock, flags); + sk->sk_error_report(sk); + + mm_unaccount_pinned_pages(&znotif->z_mmp); +} + /* * This relies on dma_map_sg() not touching sg[].page during merging. */ static void rds_message_purge(struct rds_message *rm) { - unsigned long i; + unsigned long i, flags; + bool zcopy = false; if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags))) return; + spin_lock_irqsave(&rm->m_rs_lock, flags); + if (rm->m_rs) { + struct rds_sock *rs = rm->m_rs; + + if (rm->data.op_mmp_znotifier) { + zcopy = true; + rds_rm_zerocopy_callback(rs, rm->data.op_mmp_znotifier); + rm->data.op_mmp_znotifier = NULL; + } + sock_put(rds_rs_to_sk(rs)); + rm->m_rs = NULL; + } + spin_unlock_irqrestore(&rm->m_rs_lock, flags); + for (i = 0; i < rm->data.op_nents; i++) { - rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i])); /* XXX will have to put_page for page refs */ - __free_page(sg_page(&rm->data.op_sg[i])); + if (!zcopy) + __free_page(sg_page(&rm->data.op_sg[i])); + else + put_page(sg_page(&rm->data.op_sg[i])); } rm->data.op_nents = 0; @@ -266,12 +341,14 @@ struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned in return rm; } -int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from) +int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from, + bool zcopy) { unsigned long to_copy, nbytes; unsigned long sg_off; struct scatterlist *sg; int ret = 0; + int length = iov_iter_count(from); rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from)); @@ -281,6 +358,53 @@ int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from) sg = rm->data.op_sg; sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */ + if (zcopy) { + int total_copied = 0; + struct sk_buff *skb; + + skb = alloc_skb(SO_EE_ORIGIN_MAX_ZCOOKIES * sizeof(u32), + GFP_KERNEL); + if (!skb) + return -ENOMEM; + rm->data.op_mmp_znotifier = RDS_ZCOPY_SKB(skb); + if (mm_account_pinned_pages(&rm->data.op_mmp_znotifier->z_mmp, + length)) { + ret = -ENOMEM; + goto err; + } + while (iov_iter_count(from)) { + struct page *pages; + size_t start; + ssize_t copied; + + copied = iov_iter_get_pages(from, &pages, PAGE_SIZE, + 1, &start); + if (copied < 0) { + struct mmpin *mmp; + int i; + + for (i = 0; i < rm->data.op_nents; i++) + put_page(sg_page(&rm->data.op_sg[i])); + mmp = &rm->data.op_mmp_znotifier->z_mmp; + mm_unaccount_pinned_pages(mmp); + ret = -EFAULT; + goto err; + } + total_copied += copied; + iov_iter_advance(from, copied); + length -= copied; + sg_set_page(sg, pages, copied, start); + rm->data.op_nents++; + sg++; + } + WARN_ON_ONCE(length != 0); + return ret; +err: + consume_skb(skb); + rm->data.op_mmp_znotifier = NULL; + return ret; + } /* zcopy */ + while (iov_iter_count(from)) { if (!sg_page(sg)) { ret = rds_page_remainder_alloc(sg, iov_iter_count(from), |