Update for 3.8 kernels

git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@4768 d57e44dd-8a1f-0410-8b47-8ef2f437770f
This commit is contained in:
Vladislav Bolkhovitin
2013-02-23 00:44:56 +00:00
parent 10ca1d2f20
commit 79bf4e77c6
3 changed files with 928 additions and 1 deletions

View File

@@ -0,0 +1,397 @@
=== modified file 'drivers/net/macvtap.c'
--- old/drivers/net/macvtap.c 2013-02-22 21:12:31 +0000
+++ new/drivers/net/macvtap.c 2013-02-23 00:18:18 +0000
@@ -536,7 +536,7 @@ static int zerocopy_sg_from_iovec(struct
num_pages = get_user_pages_fast(base, size, 0, &page[i]);
if (num_pages != size) {
for (i = 0; i < num_pages; i++)
- put_page(page[i]);
+ net_put_page(page[i]);
return -EFAULT;
}
truesize = size * PAGE_SIZE;
=== modified file 'drivers/net/tun.c'
--- old/drivers/net/tun.c 2013-02-22 21:12:31 +0000
+++ new/drivers/net/tun.c 2013-02-23 00:18:18 +0000
@@ -1012,7 +1012,7 @@ static int zerocopy_sg_from_iovec(struct
num_pages = get_user_pages_fast(base, size, 0, &page[i]);
if (num_pages != size) {
for (i = 0; i < num_pages; i++)
- put_page(page[i]);
+ net_put_page(page[i]);
return -EFAULT;
}
truesize = size * PAGE_SIZE;
=== modified file 'drivers/net/vmxnet3/vmxnet3_drv.c'
--- old/drivers/net/vmxnet3/vmxnet3_drv.c 2013-02-22 21:12:31 +0000
+++ new/drivers/net/vmxnet3/vmxnet3_drv.c 2013-02-23 00:18:18 +0000
@@ -1368,7 +1368,7 @@ vmxnet3_rq_cleanup(struct vmxnet3_rx_que
rq->buf_info[ring_idx][i].page) {
pci_unmap_page(adapter->pdev, rxd->addr,
rxd->len, PCI_DMA_FROMDEVICE);
- put_page(rq->buf_info[ring_idx][i].page);
+ net_put_page(rq->buf_info[ring_idx][i].page);
rq->buf_info[ring_idx][i].page = NULL;
}
}
=== modified file 'drivers/net/xen-netback/netback.c'
--- old/drivers/net/xen-netback/netback.c 2013-02-22 21:12:31 +0000
+++ new/drivers/net/xen-netback/netback.c 2013-02-23 00:18:18 +0000
@@ -1090,7 +1090,7 @@ static void xen_netbk_fill_frags(struct
skb->truesize += txp->size;
/* Take an extra reference to offset xen_netbk_idx_release */
- get_page(netbk->mmap_pages[pending_idx]);
+ net_get_page(netbk->mmap_pages[pending_idx]);
xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY);
}
}
@@ -1549,7 +1549,7 @@ static void xen_netbk_idx_release(struct
xenvif_put(vif);
netbk->mmap_pages[pending_idx]->mapping = 0;
- put_page(netbk->mmap_pages[pending_idx]);
+ net_put_page(netbk->mmap_pages[pending_idx]);
netbk->mmap_pages[pending_idx] = NULL;
}
=== modified file 'include/linux/mm_types.h'
--- old/include/linux/mm_types.h 2013-02-22 21:12:31 +0000
+++ new/include/linux/mm_types.h 2013-02-23 00:18:18 +0000
@@ -176,6 +176,17 @@ struct page {
#ifdef CONFIG_NUMA_BALANCING
int _last_nid;
#endif
+
+#if defined(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION)
+ /*
+ * Used to implement support for notification on zero-copy TCP transfer
+ * completion. It might look as not good to have this field here and
+ * it's better to have it in struct sk_buff, but it would make the code
+ * much more complicated and fragile, since all skb then would have to
+ * contain only pages with the same value in this field.
+ */
+ void *net_priv;
+#endif
}
/*
* The struct page can be forced to be double word aligned so that atomic ops
=== modified file 'include/linux/net.h'
--- old/include/linux/net.h 2013-02-22 21:12:31 +0000
+++ new/include/linux/net.h 2013-02-23 00:18:18 +0000
@@ -19,6 +19,7 @@
#define _LINUX_NET_H
#include <linux/stringify.h>
+#include <linux/mm.h>
#include <linux/random.h>
#include <linux/wait.h>
#include <linux/fcntl.h> /* For O_CLOEXEC and O_NONBLOCK */
@@ -270,6 +271,45 @@ extern int kernel_sock_ioctl(struct sock
extern int kernel_sock_shutdown(struct socket *sock,
enum sock_shutdown_cmd how);
+#if defined(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION)
+/* Support for notification on zero-copy TCP transfer completion */
+typedef void (*net_get_page_callback_t)(struct page *page);
+typedef void (*net_put_page_callback_t)(struct page *page);
+
+extern net_get_page_callback_t net_get_page_callback;
+extern net_put_page_callback_t net_put_page_callback;
+
+extern int net_set_get_put_page_callbacks(
+ net_get_page_callback_t get_callback,
+ net_put_page_callback_t put_callback);
+
+/*
+ * See comment for net_set_get_put_page_callbacks() why those functions
+ * don't need any protection.
+ */
+static inline void net_get_page(struct page *page)
+{
+ if (page->net_priv != 0)
+ net_get_page_callback(page);
+ get_page(page);
+}
+static inline void net_put_page(struct page *page)
+{
+ if (page->net_priv != 0)
+ net_put_page_callback(page);
+ put_page(page);
+}
+#else
+static inline void net_get_page(struct page *page)
+{
+ get_page(page);
+}
+static inline void net_put_page(struct page *page)
+{
+ put_page(page);
+}
+#endif /* CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION */
+
#define MODULE_ALIAS_NETPROTO(proto) \
MODULE_ALIAS("net-pf-" __stringify(proto))
=== modified file 'include/linux/skbuff.h'
--- old/include/linux/skbuff.h 2013-02-22 21:12:31 +0000
+++ new/include/linux/skbuff.h 2013-02-23 00:18:18 +0000
@@ -1944,7 +1944,7 @@ static inline struct page *skb_frag_page
*/
static inline void __skb_frag_ref(skb_frag_t *frag)
{
- get_page(skb_frag_page(frag));
+ net_get_page(skb_frag_page(frag));
}
/**
@@ -1967,7 +1967,7 @@ static inline void skb_frag_ref(struct s
*/
static inline void __skb_frag_unref(skb_frag_t *frag)
{
- put_page(skb_frag_page(frag));
+ net_put_page(skb_frag_page(frag));
}
/**
=== modified file 'net/Kconfig'
--- old/net/Kconfig 2013-02-22 21:12:31 +0000
+++ new/net/Kconfig 2013-02-23 00:18:18 +0000
@@ -74,6 +74,18 @@ config INET
Short answer: say Y.
+config TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION
+ bool "TCP/IP zero-copy transfer completion notification"
+ depends on INET
+ default SCST_ISCSI
+ ---help---
+ Adds support for sending a notification upon completion of a
+ zero-copy TCP/IP transfer. This can speed up certain TCP/IP
+ software. Currently this is only used by the iSCSI target driver
+ iSCSI-SCST.
+
+ If unsure, say N.
+
if INET
source "net/ipv4/Kconfig"
source "net/ipv6/Kconfig"
=== modified file 'net/core/skbuff.c'
--- old/net/core/skbuff.c 2013-02-22 21:12:31 +0000
+++ new/net/core/skbuff.c 2013-02-23 00:18:18 +0000
@@ -77,13 +77,13 @@ static struct kmem_cache *skbuff_fclone_
static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- put_page(buf->page);
+ net_put_page(buf->page);
}
static void sock_pipe_buf_get(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- get_page(buf->page);
+ net_get_page(buf->page);
}
static int sock_pipe_buf_steal(struct pipe_inode_info *pipe,
@@ -441,7 +441,7 @@ struct sk_buff *__netdev_alloc_skb(struc
if (likely(data)) {
skb = build_skb(data, fragsz);
if (unlikely(!skb))
- put_page(virt_to_head_page(data));
+ net_put_page(virt_to_head_page(data));
}
} else {
skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask,
@@ -494,7 +494,7 @@ static void skb_clone_fraglist(struct sk
static void skb_free_head(struct sk_buff *skb)
{
if (skb->head_frag)
- put_page(virt_to_head_page(skb->head));
+ net_put_page(virt_to_head_page(skb->head));
else
kfree(skb->head);
}
@@ -803,7 +803,7 @@ int skb_copy_ubufs(struct sk_buff *skb,
if (!page) {
while (head) {
struct page *next = (struct page *)head->private;
- put_page(head);
+ net_put_page(head);
head = next;
}
return -ENOMEM;
@@ -1644,7 +1644,7 @@ EXPORT_SYMBOL(skb_copy_bits);
*/
static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i)
{
- put_page(spd->pages[i]);
+ net_put_page(spd->pages[i]);
}
static struct page *linear_to_page(struct page *page, unsigned int *len,
@@ -1697,7 +1697,7 @@ static bool spd_fill_page(struct splice_
spd->partial[spd->nr_pages - 1].len += *len;
return false;
}
- get_page(page);
+ net_get_page(page);
spd->pages[spd->nr_pages] = page;
spd->partial[spd->nr_pages].len = *len;
spd->partial[spd->nr_pages].offset = offset;
=== modified file 'net/core/sock.c'
--- old/net/core/sock.c 2013-02-22 21:12:31 +0000
+++ new/net/core/sock.c 2013-02-23 00:18:18 +0000
@@ -1803,7 +1803,7 @@ bool sk_page_frag_refill(struct sock *sk
}
if (pfrag->offset < pfrag->size)
return true;
- put_page(pfrag->page);
+ net_put_page(pfrag->page);
}
/* We restrict high order allocations to users that can afford to wait */
@@ -2503,7 +2503,7 @@ void sk_common_release(struct sock *sk)
sk_refcnt_debug_release(sk);
if (sk->sk_frag.page) {
- put_page(sk->sk_frag.page);
+ net_put_page(sk->sk_frag.page);
sk->sk_frag.page = NULL;
}
=== modified file 'net/ipv4/Makefile'
--- old/net/ipv4/Makefile 2013-02-22 21:12:31 +0000
+++ new/net/ipv4/Makefile 2013-02-23 00:18:18 +0000
@@ -51,6 +51,7 @@ obj-$(CONFIG_TCP_CONG_YEAH) += tcp_yeah.
obj-$(CONFIG_TCP_CONG_ILLINOIS) += tcp_illinois.o
obj-$(CONFIG_MEMCG_KMEM) += tcp_memcontrol.o
obj-$(CONFIG_NETLABEL) += cipso_ipv4.o
+obj-$(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION) += tcp_zero_copy.o
obj-$(CONFIG_XFRM) += xfrm4_policy.o xfrm4_state.o xfrm4_input.o \
xfrm4_output.o
=== modified file 'net/ipv4/ip_output.c'
--- old/net/ipv4/ip_output.c 2013-02-22 21:12:31 +0000
+++ new/net/ipv4/ip_output.c 2013-02-23 00:18:18 +0000
@@ -1006,7 +1006,7 @@ alloc_new_skb:
__skb_fill_page_desc(skb, i, pfrag->page,
pfrag->offset, 0);
skb_shinfo(skb)->nr_frags = ++i;
- get_page(pfrag->page);
+ net_get_page(pfrag->page);
}
copy = min_t(int, copy, pfrag->size - pfrag->offset);
if (getfrag(from,
@@ -1227,7 +1227,7 @@ ssize_t ip_append_page(struct sock *sk,
if (skb_can_coalesce(skb, i, page, offset)) {
skb_frag_size_add(&skb_shinfo(skb)->frags[i-1], len);
} else if (i < MAX_SKB_FRAGS) {
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, offset, len);
} else {
err = -EMSGSIZE;
=== modified file 'net/ipv4/tcp.c'
--- old/net/ipv4/tcp.c 2013-02-22 21:12:31 +0000
+++ new/net/ipv4/tcp.c 2013-02-23 00:18:18 +0000
@@ -892,7 +892,7 @@ new_segment:
if (can_coalesce) {
skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
} else {
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, offset, copy);
}
@@ -1180,7 +1180,7 @@ new_segment:
} else {
skb_fill_page_desc(skb, i, pfrag->page,
pfrag->offset, copy);
- get_page(pfrag->page);
+ net_get_page(pfrag->page);
}
pfrag->offset += copy;
}
=== added file 'net/ipv4/tcp_zero_copy.c'
--- old/net/ipv4/tcp_zero_copy.c 1970-01-01 00:00:00 +0000
+++ new/net/ipv4/tcp_zero_copy.c 2013-02-23 00:18:18 +0000
@@ -0,0 +1,50 @@
+/*
+ * Support routines for TCP zero copy transmit
+ *
+ * Created by Vladislav Bolkhovitin
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/export.h>
+#include <linux/skbuff.h>
+
+net_get_page_callback_t net_get_page_callback __read_mostly;
+EXPORT_SYMBOL_GPL(net_get_page_callback);
+
+net_put_page_callback_t net_put_page_callback __read_mostly;
+EXPORT_SYMBOL_GPL(net_put_page_callback);
+
+/*
+ * Caller of this function must ensure that at the moment when it's called
+ * there are no pages in the system with net_priv field set to non-zero
+ * value. Hence, this function, as well as net_get_page() and net_put_page(),
+ * don't need any protection.
+ */
+int net_set_get_put_page_callbacks(
+ net_get_page_callback_t get_callback,
+ net_put_page_callback_t put_callback)
+{
+ int res = 0;
+
+ if ((net_get_page_callback != NULL) && (get_callback != NULL) &&
+ (net_get_page_callback != get_callback)) {
+ res = -EBUSY;
+ goto out;
+ }
+
+ if ((net_put_page_callback != NULL) && (put_callback != NULL) &&
+ (net_put_page_callback != put_callback)) {
+ res = -EBUSY;
+ goto out;
+ }
+
+ net_get_page_callback = get_callback;
+ net_put_page_callback = put_callback;
+
+out:
+ return res;
+}
+EXPORT_SYMBOL_GPL(net_set_get_put_page_callbacks);
=== modified file 'net/ipv6/ip6_output.c'
--- old/net/ipv6/ip6_output.c 2013-02-22 21:12:31 +0000
+++ new/net/ipv6/ip6_output.c 2013-02-23 00:18:18 +0000
@@ -1451,7 +1451,7 @@ alloc_new_skb:
__skb_fill_page_desc(skb, i, pfrag->page,
pfrag->offset, 0);
skb_shinfo(skb)->nr_frags = ++i;
- get_page(pfrag->page);
+ net_get_page(pfrag->page);
}
copy = min_t(int, copy, pfrag->size - pfrag->offset);
if (getfrag(from,

View File

@@ -1798,7 +1798,10 @@ EXPORT_SYMBOL(qla2xxx_del_vtarget);
/*
* PCI driver interface
*/
static int __devinit
static int
#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0))
__devinit
#endif
qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
{
int ret = -ENODEV;

View File

@@ -0,0 +1,527 @@
=== modified file 'block/blk-map.c'
--- old/block/blk-map.c 2013-02-22 21:12:31 +0000
+++ new/block/blk-map.c 2013-02-23 00:07:57 +0000
@@ -5,6 +5,8 @@
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
#include <scsi/sg.h> /* for struct sg_iovec */
#include "blk.h"
@@ -275,6 +277,337 @@ int blk_rq_unmap_user(struct bio *bio)
}
EXPORT_SYMBOL(blk_rq_unmap_user);
+struct blk_kern_sg_work {
+ atomic_t bios_inflight;
+ struct sg_table sg_table;
+ struct scatterlist *src_sgl;
+};
+
+static void blk_free_kern_sg_work(struct blk_kern_sg_work *bw)
+{
+ struct sg_table *sgt = &bw->sg_table;
+ struct scatterlist *sg;
+ int i;
+
+ for_each_sg(sgt->sgl, sg, sgt->orig_nents, i) {
+ struct page *pg = sg_page(sg);
+ if (pg == NULL)
+ break;
+ __free_page(pg);
+ }
+
+ sg_free_table(sgt);
+ kfree(bw);
+ return;
+}
+
+static void blk_bio_map_kern_endio(struct bio *bio, int err)
+{
+ struct blk_kern_sg_work *bw = bio->bi_private;
+
+ if (bw != NULL) {
+ /* Decrement the bios in processing and, if zero, free */
+ BUG_ON(atomic_read(&bw->bios_inflight) <= 0);
+ if (atomic_dec_and_test(&bw->bios_inflight)) {
+ if ((bio_data_dir(bio) == READ) && (err == 0)) {
+ unsigned long flags;
+
+ local_irq_save(flags); /* to protect KMs */
+ sg_copy(bw->src_sgl, bw->sg_table.sgl, 0, 0);
+ local_irq_restore(flags);
+ }
+ blk_free_kern_sg_work(bw);
+ }
+ }
+
+ bio_put(bio);
+ return;
+}
+
+static int blk_rq_copy_kern_sg(struct request *rq, struct scatterlist *sgl,
+ int nents, struct blk_kern_sg_work **pbw,
+ gfp_t gfp, gfp_t page_gfp)
+{
+ int res = 0, i;
+ struct scatterlist *sg;
+ struct scatterlist *new_sgl;
+ int new_sgl_nents;
+ size_t len = 0, to_copy;
+ struct blk_kern_sg_work *bw;
+
+ bw = kzalloc(sizeof(*bw), gfp);
+ if (bw == NULL)
+ goto out;
+
+ bw->src_sgl = sgl;
+
+ for_each_sg(sgl, sg, nents, i)
+ len += sg->length;
+ to_copy = len;
+
+ new_sgl_nents = PFN_UP(len);
+
+ res = sg_alloc_table(&bw->sg_table, new_sgl_nents, gfp);
+ if (res != 0)
+ goto err_free;
+
+ new_sgl = bw->sg_table.sgl;
+
+ for_each_sg(new_sgl, sg, new_sgl_nents, i) {
+ struct page *pg;
+
+ pg = alloc_page(page_gfp);
+ if (pg == NULL)
+ goto err_free;
+
+ sg_assign_page(sg, pg);
+ sg->length = min_t(size_t, PAGE_SIZE, len);
+
+ len -= PAGE_SIZE;
+ }
+
+ if (rq_data_dir(rq) == WRITE) {
+ /*
+ * We need to limit amount of copied data to to_copy, because
+ * sgl might have the last element in sgl not marked as last in
+ * SG chaining.
+ */
+ sg_copy(new_sgl, sgl, 0, to_copy);
+ }
+
+ *pbw = bw;
+ /*
+ * REQ_COPY_USER name is misleading. It should be something like
+ * REQ_HAS_TAIL_SPACE_FOR_PADDING.
+ */
+ rq->cmd_flags |= REQ_COPY_USER;
+
+out:
+ return res;
+
+err_free:
+ blk_free_kern_sg_work(bw);
+ res = -ENOMEM;
+ goto out;
+}
+
+static int __blk_rq_map_kern_sg(struct request *rq, struct scatterlist *sgl,
+ int nents, struct blk_kern_sg_work *bw, gfp_t gfp)
+{
+ int res;
+ struct request_queue *q = rq->q;
+ int rw = rq_data_dir(rq);
+ int max_nr_vecs, i;
+ size_t tot_len;
+ bool need_new_bio;
+ struct scatterlist *sg, *prev_sg = NULL;
+ struct bio *bio = NULL, *hbio = NULL, *tbio = NULL;
+ int bios;
+
+ if (unlikely((sgl == NULL) || (sgl->length == 0) || (nents <= 0))) {
+ WARN_ON(1);
+ res = -EINVAL;
+ goto out;
+ }
+
+ /*
+ * Let's keep each bio allocation inside a single page to decrease
+ * probability of failure.
+ */
+ max_nr_vecs = min_t(size_t,
+ ((PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec)),
+ BIO_MAX_PAGES);
+
+ need_new_bio = true;
+ tot_len = 0;
+ bios = 0;
+ for_each_sg(sgl, sg, nents, i) {
+ struct page *page = sg_page(sg);
+ void *page_addr = page_address(page);
+ size_t len = sg->length, l;
+ size_t offset = sg->offset;
+
+ tot_len += len;
+ prev_sg = sg;
+
+ /*
+ * Each segment must be aligned on DMA boundary and
+ * not on stack. The last one may have unaligned
+ * length as long as the total length is aligned to
+ * DMA padding alignment.
+ */
+ if (i == nents - 1)
+ l = 0;
+ else
+ l = len;
+ if (((sg->offset | l) & queue_dma_alignment(q)) ||
+ (page_addr && object_is_on_stack(page_addr + sg->offset))) {
+ res = -EINVAL;
+ goto out_free_bios;
+ }
+
+ while (len > 0) {
+ size_t bytes;
+ int rc;
+
+ if (need_new_bio) {
+ bio = bio_kmalloc(gfp, max_nr_vecs);
+ if (bio == NULL) {
+ res = -ENOMEM;
+ goto out_free_bios;
+ }
+
+ if (rw == WRITE)
+ bio->bi_rw |= REQ_WRITE;
+
+ bios++;
+ bio->bi_private = bw;
+ bio->bi_end_io = blk_bio_map_kern_endio;
+
+ if (hbio == NULL)
+ hbio = tbio = bio;
+ else
+ tbio = tbio->bi_next = bio;
+ }
+
+ bytes = min_t(size_t, len, PAGE_SIZE - offset);
+
+ rc = bio_add_pc_page(q, bio, page, bytes, offset);
+ if (rc < bytes) {
+ if (unlikely(need_new_bio || (rc < 0))) {
+ if (rc < 0)
+ res = rc;
+ else
+ res = -EIO;
+ goto out_free_bios;
+ } else {
+ need_new_bio = true;
+ len -= rc;
+ offset += rc;
+ continue;
+ }
+ }
+
+ need_new_bio = false;
+ offset = 0;
+ len -= bytes;
+ page = nth_page(page, 1);
+ }
+ }
+
+ if (hbio == NULL) {
+ res = -EINVAL;
+ goto out_free_bios;
+ }
+
+ /* Total length must be aligned on DMA padding alignment */
+ if ((tot_len & q->dma_pad_mask) &&
+ !(rq->cmd_flags & REQ_COPY_USER)) {
+ res = -EINVAL;
+ goto out_free_bios;
+ }
+
+ if (bw != NULL)
+ atomic_set(&bw->bios_inflight, bios);
+
+ while (hbio != NULL) {
+ bio = hbio;
+ hbio = hbio->bi_next;
+ bio->bi_next = NULL;
+
+ blk_queue_bounce(q, &bio);
+
+ res = blk_rq_append_bio(q, rq, bio);
+ if (unlikely(res != 0)) {
+ bio->bi_next = hbio;
+ hbio = bio;
+ /* We can have one or more bios bounced */
+ goto out_unmap_bios;
+ }
+ }
+
+ res = 0;
+
+ rq->buffer = NULL;
+out:
+ return res;
+
+out_unmap_bios:
+ blk_rq_unmap_kern_sg(rq, res);
+
+out_free_bios:
+ while (hbio != NULL) {
+ bio = hbio;
+ hbio = hbio->bi_next;
+ bio_put(bio);
+ }
+ goto out;
+}
+
+/**
+ * blk_rq_map_kern_sg - map kernel data to a request, for REQ_TYPE_BLOCK_PC
+ * @rq: request to fill
+ * @sgl: area to map
+ * @nents: number of elements in @sgl
+ * @gfp: memory allocation flags
+ *
+ * Description:
+ * Data will be mapped directly if possible. Otherwise a bounce
+ * buffer will be used.
+ */
+int blk_rq_map_kern_sg(struct request *rq, struct scatterlist *sgl,
+ int nents, gfp_t gfp)
+{
+ int res;
+
+ res = __blk_rq_map_kern_sg(rq, sgl, nents, NULL, gfp);
+ if (unlikely(res != 0)) {
+ struct blk_kern_sg_work *bw = NULL;
+
+ res = blk_rq_copy_kern_sg(rq, sgl, nents, &bw,
+ gfp, rq->q->bounce_gfp | gfp);
+ if (unlikely(res != 0))
+ goto out;
+
+ res = __blk_rq_map_kern_sg(rq, bw->sg_table.sgl,
+ bw->sg_table.nents, bw, gfp);
+ if (res != 0) {
+ blk_free_kern_sg_work(bw);
+ goto out;
+ }
+ }
+
+ rq->buffer = NULL;
+
+out:
+ return res;
+}
+EXPORT_SYMBOL(blk_rq_map_kern_sg);
+
+/**
+ * blk_rq_unmap_kern_sg - unmap a request with kernel sg
+ * @rq: request to unmap
+ * @err: non-zero error code
+ *
+ * Description:
+ * Unmap a rq previously mapped by blk_rq_map_kern_sg(). Must be called
+ * only in case of an error!
+ */
+void blk_rq_unmap_kern_sg(struct request *rq, int err)
+{
+ struct bio *bio = rq->bio;
+
+ while (bio) {
+ struct bio *b = bio;
+ bio = bio->bi_next;
+ b->bi_end_io(b, err);
+ }
+ rq->bio = NULL;
+
+ return;
+}
+EXPORT_SYMBOL(blk_rq_unmap_kern_sg);
+
/**
* blk_rq_map_kern - map kernel data to a request, for REQ_TYPE_BLOCK_PC usage
* @q: request queue where request should be inserted
=== modified file 'include/linux/blkdev.h'
--- old/include/linux/blkdev.h 2013-02-22 21:12:31 +0000
+++ new/include/linux/blkdev.h 2013-02-22 21:21:51 +0000
@@ -668,6 +668,8 @@ extern unsigned long blk_max_low_pfn, bl
#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
#define BLK_MIN_SG_TIMEOUT (7 * HZ)
+#define SCSI_EXEC_REQ_FIFO_DEFINED
+
#ifdef CONFIG_BOUNCE
extern int init_emergency_isa_pool(void);
extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
@@ -787,6 +789,9 @@ extern int blk_rq_map_kern(struct reques
extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
struct rq_map_data *, struct sg_iovec *, int,
unsigned int, gfp_t);
+extern int blk_rq_map_kern_sg(struct request *rq, struct scatterlist *sgl,
+ int nents, gfp_t gfp);
+extern void blk_rq_unmap_kern_sg(struct request *rq, int err);
extern int blk_execute_rq(struct request_queue *, struct gendisk *,
struct request *, int);
extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
=== modified file 'include/linux/scatterlist.h'
--- old/include/linux/scatterlist.h 2013-02-22 21:12:31 +0000
+++ new/include/linux/scatterlist.h 2013-02-22 21:21:51 +0000
@@ -8,6 +8,7 @@
#include <asm/types.h>
#include <asm/scatterlist.h>
#include <asm/io.h>
+#include <asm/kmap_types.h>
struct sg_table {
struct scatterlist *sgl; /* the list */
@@ -225,6 +226,9 @@ size_t sg_copy_from_buffer(struct scatte
size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents,
void *buf, size_t buflen);
+int sg_copy(struct scatterlist *dst_sg, struct scatterlist *src_sg,
+ int nents_to_copy, size_t copy_len);
+
/*
* Maximum number of entries that will be allocated in one piece, if
* a list larger than this is required then chaining will be utilized.
=== modified file 'lib/scatterlist.c'
--- old/lib/scatterlist.c 2013-02-22 21:12:31 +0000
+++ new/lib/scatterlist.c 2013-02-23 00:07:57 +0000
@@ -593,3 +593,126 @@ size_t sg_copy_to_buffer(struct scatterl
return sg_copy_buffer(sgl, nents, buf, buflen, 1);
}
EXPORT_SYMBOL(sg_copy_to_buffer);
+
+/*
+ * Can switch to the next dst_sg element, so, to copy to strictly only
+ * one dst_sg element, it must be either last in the chain, or
+ * copy_len == dst_sg->length.
+ */
+static int sg_copy_elem(struct scatterlist **pdst_sg, size_t *pdst_len,
+ size_t *pdst_offs, struct scatterlist *src_sg,
+ size_t copy_len)
+{
+ int res = 0;
+ struct scatterlist *dst_sg;
+ size_t src_len, dst_len, src_offs, dst_offs;
+ struct page *src_page, *dst_page;
+
+ dst_sg = *pdst_sg;
+ dst_len = *pdst_len;
+ dst_offs = *pdst_offs;
+ dst_page = sg_page(dst_sg);
+
+ src_page = sg_page(src_sg);
+ src_len = src_sg->length;
+ src_offs = src_sg->offset;
+
+ do {
+ void *saddr, *daddr;
+ size_t n;
+
+ saddr = kmap_atomic(src_page + (src_offs >> PAGE_SHIFT)) +
+ (src_offs & ~PAGE_MASK);
+ daddr = kmap_atomic(dst_page + (dst_offs >> PAGE_SHIFT)) +
+ (dst_offs & ~PAGE_MASK);
+
+ if (((src_offs & ~PAGE_MASK) == 0) &&
+ ((dst_offs & ~PAGE_MASK) == 0) &&
+ (src_len >= PAGE_SIZE) && (dst_len >= PAGE_SIZE) &&
+ (copy_len >= PAGE_SIZE)) {
+ copy_page(daddr, saddr);
+ n = PAGE_SIZE;
+ } else {
+ n = min_t(size_t, PAGE_SIZE - (dst_offs & ~PAGE_MASK),
+ PAGE_SIZE - (src_offs & ~PAGE_MASK));
+ n = min(n, src_len);
+ n = min(n, dst_len);
+ n = min_t(size_t, n, copy_len);
+ memcpy(daddr, saddr, n);
+ }
+ dst_offs += n;
+ src_offs += n;
+
+ kunmap_atomic(saddr);
+ kunmap_atomic(daddr);
+
+ res += n;
+ copy_len -= n;
+ if (copy_len == 0)
+ goto out;
+
+ src_len -= n;
+ dst_len -= n;
+ if (dst_len == 0) {
+ dst_sg = sg_next(dst_sg);
+ if (dst_sg == NULL)
+ goto out;
+ dst_page = sg_page(dst_sg);
+ dst_len = dst_sg->length;
+ dst_offs = dst_sg->offset;
+ }
+ } while (src_len > 0);
+
+out:
+ *pdst_sg = dst_sg;
+ *pdst_len = dst_len;
+ *pdst_offs = dst_offs;
+ return res;
+}
+
+/**
+ * sg_copy - copy one SG vector to another
+ * @dst_sg: destination SG
+ * @src_sg: source SG
+ * @nents_to_copy: maximum number of entries to copy
+ * @copy_len: maximum amount of data to copy. If 0, then copy all.
+ *
+ * Description:
+ * Data from the source SG vector will be copied to the destination SG
+ * vector. End of the vectors will be determined by sg_next() returning
+ * NULL. Returns number of bytes copied.
+ */
+int sg_copy(struct scatterlist *dst_sg, struct scatterlist *src_sg,
+ int nents_to_copy, size_t copy_len)
+{
+ int res = 0;
+ size_t dst_len, dst_offs;
+
+ if (copy_len == 0)
+ copy_len = 0x7FFFFFFF; /* copy all */
+
+ if (nents_to_copy == 0)
+ nents_to_copy = 0x7FFFFFFF; /* copy all */
+
+ dst_len = dst_sg->length;
+ dst_offs = dst_sg->offset;
+
+ do {
+ int copied = sg_copy_elem(&dst_sg, &dst_len, &dst_offs,
+ src_sg, copy_len);
+ copy_len -= copied;
+ res += copied;
+ if ((copy_len == 0) || (dst_sg == NULL))
+ goto out;
+
+ nents_to_copy--;
+ if (nents_to_copy == 0)
+ goto out;
+
+ src_sg = sg_next(src_sg);
+ } while (src_sg != NULL);
+
+out:
+ return res;
+}
+EXPORT_SYMBOL(sg_copy);