diff options
Diffstat (limited to 'net/rds/message.c')
| -rw-r--r-- | net/rds/message.c | 163 |
1 files changed, 156 insertions, 7 deletions
diff --git a/net/rds/message.c b/net/rds/message.c index 4318cc9b78f7..a35f76971984 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" @@ -45,7 +48,6 @@ static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = { [RDS_EXTHDR_GEN_NUM] = sizeof(u32), }; - void rds_message_addref(struct rds_message *rm) { rdsdebug("addref rm %p ref %d\n", rm, refcount_read(&rm->m_refcount)); @@ -53,20 +55,107 @@ void rds_message_addref(struct rds_message *rm) } EXPORT_SYMBOL_GPL(rds_message_addref); +static inline bool rds_zcookie_add(struct rds_msg_zcopy_info *info, u32 cookie) +{ + struct rds_zcopy_cookies *ck = &info->zcookies; + int ncookies = ck->num; + + if (ncookies == RDS_MAX_ZCOOKIES) + return false; + ck->cookies[ncookies] = cookie; + ck->num = ++ncookies; + return true; +} + +static struct rds_msg_zcopy_info *rds_info_from_znotifier(struct rds_znotifier *znotif) +{ + return container_of(znotif, struct rds_msg_zcopy_info, znotif); +} + +void rds_notify_msg_zcopy_purge(struct rds_msg_zcopy_queue *q) +{ + unsigned long flags; + LIST_HEAD(copy); + struct rds_msg_zcopy_info *info, *tmp; + + spin_lock_irqsave(&q->lock, flags); + list_splice(&q->zcookie_head, ©); + INIT_LIST_HEAD(&q->zcookie_head); + spin_unlock_irqrestore(&q->lock, flags); + + list_for_each_entry_safe(info, tmp, ©, rs_zcookie_next) { + list_del(&info->rs_zcookie_next); + kfree(info); + } +} + +static void rds_rm_zerocopy_callback(struct rds_sock *rs, + struct rds_znotifier *znotif) +{ + struct rds_msg_zcopy_info *info; + struct rds_msg_zcopy_queue *q; + u32 cookie = znotif->z_cookie; + struct rds_zcopy_cookies *ck; + struct list_head *head; + unsigned long flags; + + mm_unaccount_pinned_pages(&znotif->z_mmp); + q = &rs->rs_zcookie_queue; + spin_lock_irqsave(&q->lock, flags); + head = &q->zcookie_head; + if (!list_empty(head)) { + info = list_entry(head, struct rds_msg_zcopy_info, + rs_zcookie_next); + if (info && rds_zcookie_add(info, cookie)) { + spin_unlock_irqrestore(&q->lock, flags); + kfree(rds_info_from_znotifier(znotif)); + /* caller invokes rds_wake_sk_sleep() */ + return; + } + } + + info = rds_info_from_znotifier(znotif); + ck = &info->zcookies; + memset(ck, 0, sizeof(*ck)); + WARN_ON(!rds_zcookie_add(info, cookie)); + list_add_tail(&q->zcookie_head, &info->rs_zcookie_next); + + spin_unlock_irqrestore(&q->lock, flags); + /* caller invokes rds_wake_sk_sleep() */ +} + /* * 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); + rds_wake_sk_sleep(rs); + 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 +355,13 @@ 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) +static int rds_message_zcopy_from_user(struct rds_message *rm, struct iov_iter *from) { - unsigned long to_copy, nbytes; - unsigned long sg_off; struct scatterlist *sg; int ret = 0; + int length = iov_iter_count(from); + int total_copied = 0; + struct rds_msg_zcopy_info *info; rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from)); @@ -279,8 +369,67 @@ int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from) * now allocate and copy in the data payload. */ sg = rm->data.op_sg; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + INIT_LIST_HEAD(&info->rs_zcookie_next); + rm->data.op_mmp_znotifier = &info->znotif; + 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: + kfree(info); + rm->data.op_mmp_znotifier = NULL; + return ret; +} + +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; + + rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from)); + + /* now allocate and copy in the data payload. */ + sg = rm->data.op_sg; sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */ + if (zcopy) + return rds_message_zcopy_from_user(rm, from); + while (iov_iter_count(from)) { if (!sg_page(sg)) { ret = rds_page_remainder_alloc(sg, iov_iter_count(from), |