[PATCH 4/18] block copy: initial XCOPY offload support

From: Mikulas Patocka
Date: Wed Oct 22 2014 - 09:27:10 EST

This is Martin Petersen's xcopy patch
(https://git.kernel.org/cgit/linux/kernel/git/mkp/linux.git/commit/?h=xcopy&id=0bdeed274e16b3038a851552188512071974eea8)
with some bug fixes, ported to the current kernel.

This patch makes it possible to use the SCSI XCOPY command.

We create a bio that has REQ_COPY flag in bi_rw and a bi_copy structure
that defines the source device. The target device is defined in the
bi_bdev and bi_iter.bi_sector.

There is a new BLKCOPY ioctl that makes it possible to use XCOPY from
userspace. The ioctl argument is a pointer to an array of four uint64_t
values.

The first value is a source byte offset, the second value is a destination
byte offset, the third value is byte length. The forth value is written by
the kernel and it represents the number of bytes that the kernel actually
copied.

Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>

---
Documentation/ABI/testing/sysfs-block | 9 +
block/bio.c | 2
block/blk-core.c | 5
block/blk-lib.c | 95 ++++++++++++
block/blk-merge.c | 7
block/blk-settings.c | 13 +
block/blk-sysfs.c | 10 +
block/compat_ioctl.c | 1
block/ioctl.c | 49 ++++++
drivers/scsi/scsi.c | 57 +++++++
drivers/scsi/sd.c | 269 +++++++++++++++++++++++++++++++++-
drivers/scsi/sd.h | 4
include/linux/bio.h | 9 -
include/linux/blk_types.h | 15 +
include/linux/blkdev.h | 15 +
include/scsi/scsi_device.h | 3
include/uapi/linux/fs.h | 1
17 files changed, 551 insertions(+), 13 deletions(-)

Index: linux-3.18-rc1/Documentation/ABI/testing/sysfs-block
===================================================================
--- linux-3.18-rc1.orig/Documentation/ABI/testing/sysfs-block 2014-10-21 01:04:13.000000000 +0200
+++ linux-3.18-rc1/Documentation/ABI/testing/sysfs-block 2014-10-21 01:04:22.000000000 +0200
@@ -228,3 +228,12 @@ Description:
write_same_max_bytes is 0, write same is not supported
by the device.

+
+What: /sys/block/<disk>/queue/copy_max_bytes
+Date: January 2014
+Contact: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
+Description:
+ Devices that support copy offloading will set this value
+ to indicate the maximum buffer size in bytes that can be
+ copied in one operation. If the copy_max_bytes is 0 the
+ device does not support copy offload.
Index: linux-3.18-rc1/block/blk-core.c
===================================================================
--- linux-3.18-rc1.orig/block/blk-core.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/blk-core.c 2014-10-21 01:04:22.000000000 +0200
@@ -1828,6 +1828,11 @@ generic_make_request_checks(struct bio *
goto end_io;
}

+ if (bio->bi_rw & REQ_COPY && !bdev_copy_offload(bio->bi_bdev)) {
+ err = -EOPNOTSUPP;
+ goto end_io;
+ }
+
/*
* Various block parts want %current->io_context and lazy ioc
* allocation ends up trading a lot of pain for a small amount of
Index: linux-3.18-rc1/block/blk-lib.c
===================================================================
--- linux-3.18-rc1.orig/block/blk-lib.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/blk-lib.c 2014-10-21 01:04:22.000000000 +0200
@@ -304,3 +304,98 @@ int blkdev_issue_zeroout(struct block_de
return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask);
}
EXPORT_SYMBOL(blkdev_issue_zeroout);
+
+/**
+ * blkdev_issue_copy - queue a copy same operation
+ * @src_bdev: source blockdev
+ * @src_sector: source sector
+ * @dst_bdev: destination blockdev
+ * @dst_sector: destination sector
+ * @nr_sects: number of sectors to copy
+ * @gfp_mask: memory allocation flags (for bio_alloc)
+ *
+ * Description:
+ * Copy a block range from source device to target device.
+ */
+int blkdev_issue_copy(struct block_device *src_bdev, sector_t src_sector,
+ struct block_device *dst_bdev, sector_t dst_sector,
+ unsigned int nr_sects, gfp_t gfp_mask)
+{
+ DECLARE_COMPLETION_ONSTACK(wait);
+ struct request_queue *sq = bdev_get_queue(src_bdev);
+ struct request_queue *dq = bdev_get_queue(dst_bdev);
+ unsigned int max_copy_sectors;
+ struct bio_batch bb;
+ int ret = 0;
+
+ if (!sq || !dq)
+ return -ENXIO;
+
+ max_copy_sectors = min(sq->limits.max_copy_sectors,
+ dq->limits.max_copy_sectors);
+
+ if (max_copy_sectors == 0)
+ return -EOPNOTSUPP;
+
+ if (src_sector + nr_sects < src_sector ||
+ dst_sector + nr_sects < dst_sector)
+ return -EINVAL;
+
+ /* Do not support overlapping copies */
+ if (src_bdev == dst_bdev &&
+ abs64((u64)dst_sector - (u64)src_sector) < nr_sects)
+ return -EOPNOTSUPP;
+
+ atomic_set(&bb.done, 1);
+ bb.error = 0;
+ bb.wait = &wait;
+
+ while (nr_sects) {
+ struct bio *bio;
+ struct bio_copy *bc;
+ unsigned int chunk;
+
+ bc = kmalloc(sizeof(struct bio_copy), gfp_mask);
+ if (!bc) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ bio = bio_alloc(gfp_mask, 1);
+ if (!bio) {
+ kfree(bc);
+ ret = -ENOMEM;
+ break;
+ }
+
+ chunk = min(nr_sects, max_copy_sectors);
+
+ bio->bi_iter.bi_sector = dst_sector;
+ bio->bi_iter.bi_size = chunk << 9;
+ bio->bi_end_io = bio_batch_end_io;
+ bio->bi_bdev = dst_bdev;
+ bio->bi_private = &bb;
+ bio->bi_copy = bc;
+
+ bc->bic_bdev = src_bdev;
+ bc->bic_sector = src_sector;
+
+ atomic_inc(&bb.done);
+ submit_bio(REQ_WRITE | REQ_COPY, bio);
+
+ src_sector += chunk;
+ dst_sector += chunk;
+ nr_sects -= chunk;
+ }
+
+ /* Wait for bios in-flight */
+ if (!atomic_dec_and_test(&bb.done))
+ wait_for_completion_io(&wait);
+
+ if (likely(!ret))
+ ret = bb.error;
+
+ return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_copy);
+
Index: linux-3.18-rc1/block/blk-merge.c
===================================================================
--- linux-3.18-rc1.orig/block/blk-merge.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/blk-merge.c 2014-10-21 01:04:22.000000000 +0200
@@ -26,10 +26,7 @@ static unsigned int __blk_recalc_rq_segm
* This should probably be returning 0, but blk_add_request_payload()
* (Christoph!!!!)
*/
- if (bio->bi_rw & REQ_DISCARD)
- return 1;
-
- if (bio->bi_rw & REQ_WRITE_SAME)
+ if (bio->bi_rw & (REQ_DISCARD | REQ_WRITE_SAME | REQ_COPY))
return 1;

fbio = bio;
@@ -205,7 +202,7 @@ static int __blk_bios_map_sg(struct requ
nsegs = 0;
cluster = blk_queue_cluster(q);

- if (bio->bi_rw & REQ_DISCARD) {
+ if (bio->bi_rw & (REQ_DISCARD | REQ_COPY)) {
/*
* This is a hack - drivers should be neither modifying the
* biovec, nor relying on bi_vcnt - but because of
Index: linux-3.18-rc1/block/blk-settings.c
===================================================================
--- linux-3.18-rc1.orig/block/blk-settings.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/blk-settings.c 2014-10-21 01:04:22.000000000 +0200
@@ -115,6 +115,7 @@ void blk_set_default_limits(struct queue
lim->max_sectors = lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS;
lim->chunk_sectors = 0;
lim->max_write_same_sectors = 0;
+ lim->max_copy_sectors = 0;
lim->max_discard_sectors = 0;
lim->discard_granularity = 0;
lim->discard_alignment = 0;
@@ -322,6 +323,18 @@ void blk_queue_max_write_same_sectors(st
EXPORT_SYMBOL(blk_queue_max_write_same_sectors);

/**
+ * blk_queue_max_copy_sectors - set max sectors for a single copy operation
+ * @q: the request queue for the device
+ * @max_copy_sectors: maximum number of sectors per copy operation
+ **/
+void blk_queue_max_copy_sectors(struct request_queue *q,
+ unsigned int max_copy_sectors)
+{
+ q->limits.max_copy_sectors = max_copy_sectors;
+}
+EXPORT_SYMBOL(blk_queue_max_copy_sectors);
+
+/**
* blk_queue_max_segments - set max hw segments for a request for this queue
* @q: the request queue for the device
* @max_segments: max number of segments
Index: linux-3.18-rc1/block/blk-sysfs.c
===================================================================
--- linux-3.18-rc1.orig/block/blk-sysfs.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/blk-sysfs.c 2014-10-21 01:04:22.000000000 +0200
@@ -166,6 +166,11 @@ static ssize_t queue_write_same_max_show
(unsigned long long)q->limits.max_write_same_sectors << 9);
}

+static ssize_t queue_copy_max_show(struct request_queue *q, char *page)
+{
+ return sprintf(page, "%llu\n",
+ (unsigned long long)q->limits.max_copy_sectors << 9);
+}

static ssize_t
queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
@@ -379,6 +384,10 @@ static struct queue_sysfs_entry queue_wr
.show = queue_write_same_max_show,
};

+static struct queue_sysfs_entry queue_copy_max_entry = {
+ .attr = {.name = "copy_max_bytes", .mode = S_IRUGO },
+ .show = queue_copy_max_show,
+};
static struct queue_sysfs_entry queue_nonrot_entry = {
.attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
.show = queue_show_nonrot,
@@ -427,6 +436,7 @@ static struct attribute *default_attrs[]
&queue_discard_max_entry.attr,
&queue_discard_zeroes_data_entry.attr,
&queue_write_same_max_entry.attr,
+ &queue_copy_max_entry.attr,
&queue_nonrot_entry.attr,
&queue_nomerges_entry.attr,
&queue_rq_affinity_entry.attr,
Index: linux-3.18-rc1/block/ioctl.c
===================================================================
--- linux-3.18-rc1.orig/block/ioctl.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/ioctl.c 2014-10-21 01:04:22.000000000 +0200
@@ -201,6 +201,31 @@ static int blk_ioctl_zeroout(struct bloc
return blkdev_issue_zeroout(bdev, start, len, GFP_KERNEL);
}

+static int blk_ioctl_copy(struct block_device *bdev, uint64_t src_offset,
+ uint64_t dst_offset, uint64_t len)
+{
+ if (src_offset & 511)
+ return -EINVAL;
+ if (dst_offset & 511)
+ return -EINVAL;
+ if (len & 511)
+ return -EINVAL;
+ src_offset >>= 9;
+ dst_offset >>= 9;
+ len >>= 9;
+
+ if (unlikely(src_offset + len < src_offset) ||
+ unlikely(src_offset + len > (i_size_read(bdev->bd_inode) >> 9)))
+ return -EINVAL;
+
+ if (unlikely(dst_offset + len < dst_offset) ||
+ unlikely(dst_offset + len > (i_size_read(bdev->bd_inode) >> 9)))
+ return -EINVAL;
+
+ return blkdev_issue_copy(bdev, src_offset, bdev, dst_offset, len,
+ GFP_KERNEL);
+}
+
static int put_ushort(unsigned long arg, unsigned short val)
{
return put_user(val, (unsigned short __user *)arg);
@@ -329,6 +354,30 @@ int blkdev_ioctl(struct block_device *bd
return blk_ioctl_zeroout(bdev, range[0], range[1]);
}

+ case BLKCOPY: {
+ uint64_t range[4];
+
+ range[3] = 0;
+
+ if (copy_to_user((void __user *)(arg + 24), &range[3], 8))
+ return -EFAULT;
+
+ if (!(mode & FMODE_WRITE))
+ return -EBADF;
+
+ if (copy_from_user(range, (void __user *)arg, 24))
+ return -EFAULT;
+
+ ret = blk_ioctl_copy(bdev, range[0], range[1], range[2]);
+ if (!ret) {
+ range[3] = range[2];
+ if (copy_to_user((void __user *)(arg + 24), &range[3], 8))
+ return -EFAULT;
+ }
+
+ return ret;
+ }
+
case HDIO_GETGEO: {
struct hd_geometry geo;

Index: linux-3.18-rc1/drivers/scsi/scsi.c
===================================================================
--- linux-3.18-rc1.orig/drivers/scsi/scsi.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/drivers/scsi/scsi.c 2014-10-21 01:04:22.000000000 +0200
@@ -995,6 +995,62 @@ int scsi_get_vpd_page(struct scsi_device
EXPORT_SYMBOL_GPL(scsi_get_vpd_page);

/**
+ * scsi_lookup_naa - Lookup NAA descriptor in VPD page 0x83
+ * @sdev: The device to ask
+ *
+ * Copy offloading requires us to know the NAA descriptor for both
+ * source and target device. This descriptor is mandatory in the Device
+ * Identification VPD page. Locate this descriptor in the returned VPD
+ * data so we don't have to do lookups for every copy command.
+ */
+static void scsi_lookup_naa(struct scsi_device *sdev)
+{
+ unsigned char *buf = sdev->vpd_pg83;
+ unsigned int len = sdev->vpd_pg83_len;
+
+ if (buf[1] != 0x83 || get_unaligned_be16(&buf[2]) == 0) {
+ sdev_printk(KERN_ERR, sdev,
+ "%s: VPD page 0x83 contains no descriptors\n",
+ __func__);
+ return;
+ }
+
+ buf += 4;
+ len -= 4;
+
+ do {
+ unsigned int desig_len = buf[3] + 4;
+
+ /* Binary code set */
+ if ((buf[0] & 0xf) != 1)
+ goto skip;
+
+ /* Target association */
+ if ((buf[1] >> 4) & 0x3)
+ goto skip;
+
+ /* NAA designator */
+ if ((buf[1] & 0xf) != 0x3)
+ goto skip;
+
+ sdev->naa = buf;
+ sdev->naa_len = desig_len;
+
+ return;
+
+ skip:
+ buf += desig_len;
+ len -= desig_len;
+
+ } while (len > 0);
+
+ sdev_printk(KERN_ERR, sdev,
+ "%s: VPD page 0x83 NAA descriptor not found\n", __func__);
+
+ return;
+}
+
+/**
* scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure
* @sdev: The device to ask
*
@@ -1078,6 +1134,7 @@ retry_pg83:
}
sdev->vpd_pg83_len = result;
sdev->vpd_pg83 = vpd_buf;
+ scsi_lookup_naa(sdev);
}
}

Index: linux-3.18-rc1/drivers/scsi/sd.c
===================================================================
--- linux-3.18-rc1.orig/drivers/scsi/sd.c 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/drivers/scsi/sd.c 2014-10-21 01:04:22.000000000 +0200
@@ -100,6 +100,7 @@ MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);

static void sd_config_discard(struct scsi_disk *, unsigned int);
static void sd_config_write_same(struct scsi_disk *);
+static void sd_config_copy(struct scsi_disk *);
static int sd_revalidate_disk(struct gendisk *);
static void sd_unlock_native_capacity(struct gendisk *disk);
static int sd_probe(struct device *);
@@ -477,6 +478,48 @@ max_write_same_blocks_store(struct devic
}
static DEVICE_ATTR_RW(max_write_same_blocks);

+static ssize_t
+max_copy_blocks_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+ return snprintf(buf, 20, "%u\n", sdkp->max_copy_blocks);
+}
+
+static ssize_t
+max_copy_blocks_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+ struct scsi_device *sdp = sdkp->device;
+ unsigned long max;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (sdp->type != TYPE_DISK)
+ return -EINVAL;
+
+ err = kstrtoul(buf, 10, &max);
+
+ if (err)
+ return err;
+
+ if (max == 0)
+ sdp->no_copy = 1;
+ else if (max <= SD_MAX_COPY_BLOCKS) {
+ sdp->no_copy = 0;
+ sdkp->max_copy_blocks = max;
+ }
+
+ sd_config_copy(sdkp);
+
+ return count;
+}
+static DEVICE_ATTR_RW(max_copy_blocks);
+
static struct attribute *sd_disk_attrs[] = {
&dev_attr_cache_type.attr,
&dev_attr_FUA.attr,
@@ -488,6 +531,7 @@ static struct attribute *sd_disk_attrs[]
&dev_attr_thin_provisioning.attr,
&dev_attr_provisioning_mode.attr,
&dev_attr_max_write_same_blocks.attr,
+ &dev_attr_max_copy_blocks.attr,
&dev_attr_max_medium_access_timeouts.attr,
NULL,
};
@@ -883,6 +927,116 @@ static int sd_setup_write_same_cmnd(stru
return ret;
}

+static void sd_config_copy(struct scsi_disk *sdkp)
+{
+ struct request_queue *q = sdkp->disk->queue;
+ unsigned int logical_block_size = sdkp->device->sector_size;
+
+ if (sdkp->device->no_copy)
+ sdkp->max_copy_blocks = 0;
+
+ /* Segment descriptor 0x02 has a 64k block limit */
+ sdkp->max_copy_blocks = min(sdkp->max_copy_blocks,
+ (u32)SD_MAX_CSD2_BLOCKS);
+
+ blk_queue_max_copy_sectors(q, sdkp->max_copy_blocks *
+ (logical_block_size >> 9));
+}
+
+static int sd_setup_copy_cmnd(struct scsi_cmnd *cmd)
+{
+ struct request *rq = cmd->request;
+ struct scsi_device *src_sdp, *dst_sdp;
+ struct gendisk *src_disk;
+ struct request_queue *src_queue, *dst_queue;
+ sector_t src_lba, dst_lba;
+ unsigned int nr_blocks, buf_len, nr_bytes = blk_rq_bytes(rq);
+ int ret;
+ struct bio *bio = rq->bio;
+ struct page *page;
+ unsigned char *buf;
+
+ if (!bio->bi_copy)
+ return BLKPREP_KILL;
+
+ dst_sdp = scsi_disk(rq->rq_disk)->device;
+ dst_queue = rq->rq_disk->queue;
+ src_disk = bio->bi_copy->bic_bdev->bd_disk;
+ src_queue = src_disk->queue;
+ if (!src_queue ||
+ src_queue->make_request_fn != blk_queue_bio ||
+ src_queue->request_fn != dst_queue->request_fn ||
+ *(struct scsi_driver **)rq->rq_disk->private_data !=
+ *(struct scsi_driver **)src_disk->private_data)
+ return BLKPREP_KILL;
+ src_sdp = scsi_disk(src_disk)->device;
+
+ if (src_sdp->no_copy || dst_sdp->no_copy)
+ return BLKPREP_KILL;
+
+ if (src_sdp->sector_size != dst_sdp->sector_size)
+ return BLKPREP_KILL;
+
+ dst_lba = blk_rq_pos(rq) >> (ilog2(dst_sdp->sector_size) - 9);
+ src_lba = bio->bi_copy->bic_sector >> (ilog2(src_sdp->sector_size) - 9);
+ nr_blocks = blk_rq_sectors(rq) >> (ilog2(dst_sdp->sector_size) - 9);
+
+ page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
+ if (!page)
+ return BLKPREP_DEFER;
+
+ buf = page_address(page);
+
+ /* Extended Copy (LID1) Parameter List (16 bytes) */
+ buf[0] = 0; /* LID */
+ buf[1] = 3 << 3; /* LID usage 11b */
+ put_unaligned_be16(32 + 32, &buf[2]); /* 32 bytes per E4 desc. */
+ put_unaligned_be32(28, &buf[8]); /* 28 bytes per B2B desc. */
+ buf += 16;
+
+ /* Source CSCD (32 bytes) */
+ buf[0] = 0xe4; /* Identification desc. */
+ memcpy(&buf[4], src_sdp->naa, src_sdp->naa_len);
+ buf += 32;
+
+ /* Destination CSCD (32 bytes) */
+ buf[0] = 0xe4; /* Identification desc. */
+ memcpy(&buf[4], dst_sdp->naa, dst_sdp->naa_len);
+ buf += 32;
+
+ /* Segment descriptor (28 bytes) */
+ buf[0] = 0x02; /* Block to block desc. */
+ put_unaligned_be16(0x18, &buf[2]); /* Descriptor length */
+ put_unaligned_be16(0, &buf[4]); /* Source is desc. 0 */
+ put_unaligned_be16(1, &buf[6]); /* Dest. is desc. 1 */
+ put_unaligned_be16(nr_blocks, &buf[10]);
+ put_unaligned_be64(src_lba, &buf[12]);
+ put_unaligned_be64(dst_lba, &buf[20]);
+
+ /* CDB */
+ cmd->cmd_len = 16;
+ memset(cmd->cmnd, 0, cmd->cmd_len);
+ cmd->cmnd[0] = EXTENDED_COPY;
+ cmd->cmnd[1] = 0; /* LID1 */
+ buf_len = 16 + 32 + 32 + 28;
+ put_unaligned_be32(buf_len, &cmd->cmnd[10]);
+ rq->timeout = SD_COPY_TIMEOUT;
+
+ rq->completion_data = page;
+ blk_add_request_payload(rq, page, buf_len);
+
+ cmd->transfersize = buf_len;
+ cmd->allowed = 0; /* don't retry */
+
+ rq->__data_len = buf_len;
+ ret = scsi_init_io(cmd, GFP_ATOMIC);
+ rq->__data_len = nr_bytes;
+
+ if (ret != BLKPREP_OK)
+ __free_page(page);
+ return ret;
+}
+
static int sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
{
struct request *rq = cmd->request;
@@ -1145,6 +1299,8 @@ static int sd_init_command(struct scsi_c
return sd_setup_discard_cmnd(cmd);
else if (rq->cmd_flags & REQ_WRITE_SAME)
return sd_setup_write_same_cmnd(cmd);
+ else if (rq->cmd_flags & REQ_COPY)
+ return sd_setup_copy_cmnd(cmd);
else if (rq->cmd_flags & REQ_FLUSH)
return sd_setup_flush_cmnd(cmd);
else
@@ -1155,7 +1311,7 @@ static void sd_uninit_command(struct scs
{
struct request *rq = SCpnt->request;

- if (rq->cmd_flags & REQ_DISCARD)
+ if (rq->cmd_flags & (REQ_DISCARD | REQ_COPY))
__free_page(rq->completion_data);

if (SCpnt->cmnd != rq->cmd) {
@@ -1698,7 +1854,8 @@ static int sd_done(struct scsi_cmnd *SCp
unsigned char op = SCpnt->cmnd[0];
unsigned char unmap = SCpnt->cmnd[1] & 8;

- if (req->cmd_flags & REQ_DISCARD || req->cmd_flags & REQ_WRITE_SAME) {
+ if (req->cmd_flags & REQ_DISCARD || req->cmd_flags & REQ_WRITE_SAME ||
+ req->cmd_flags & REQ_COPY) {
if (!result) {
good_bytes = blk_rq_bytes(req);
scsi_set_resid(SCpnt, 0);
@@ -1757,6 +1914,14 @@ static int sd_done(struct scsi_cmnd *SCp
/* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
switch (op) {
+ case EXTENDED_COPY:
+ sdkp->device->no_copy = 1;
+ sd_config_copy(sdkp);
+
+ good_bytes = 0;
+ req->__data_len = blk_rq_bytes(req);
+ req->cmd_flags |= REQ_QUIET;
+ break;
case UNMAP:
sd_config_discard(sdkp, SD_LBP_DISABLE);
break;
@@ -2745,6 +2910,105 @@ static void sd_read_write_same(struct sc
sdkp->ws10 = 1;
}

+static void sd_read_copy_operations(struct scsi_disk *sdkp,
+ unsigned char *buffer)
+{
+ struct scsi_device *sdev = sdkp->device;
+ struct scsi_sense_hdr sshdr;
+ unsigned char cdb[16];
+ unsigned int result, len, i;
+ bool b2b_desc = false, id_desc = false;
+
+ if (sdev->naa_len == 0)
+ return;
+
+ /* Verify that the device has 3PC set in INQUIRY response */
+ if (sdev->inquiry_len < 6 || (sdev->inquiry[5] & (1 << 3)) == 0)
+ return;
+
+ /* Receive Copy Operation Parameters */
+ memset(cdb, 0, 16);
+ cdb[0] = RECEIVE_COPY_RESULTS;
+ cdb[1] = 0x3;
+ put_unaligned_be32(SD_BUF_SIZE, &cdb[10]);
+
+ memset(buffer, 0, SD_BUF_SIZE);
+ result = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE,
+ buffer, SD_BUF_SIZE, &sshdr,
+ SD_TIMEOUT, SD_MAX_RETRIES, NULL);
+
+ if (!scsi_status_is_good(result)) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: Receive Copy Operating Parameters failed\n",
+ __func__);
+ return;
+ }
+
+ /* The RCOP response is a minimum of 44 bytes long. First 4
+ * bytes contain the length of the remaining buffer, i.e. 40+
+ * bytes. Trailing the defined fields is a list of supported
+ * descriptors. We need at least 2 descriptors to drive the
+ * target, hence 42.
+ */
+ len = get_unaligned_be32(&buffer[0]);
+ if (len < 42) {
+ sd_printk(KERN_ERR, sdkp, "%s: result too short (%u)\n",
+ __func__, len);
+ return;
+ }
+
+ if ((buffer[4] & 1) == 0) {
+ sd_printk(KERN_ERR, sdkp, "%s: does not support SNLID\n",
+ __func__);
+ return;
+ }
+
+ if (get_unaligned_be16(&buffer[8]) < 2) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: Need 2 or more CSCD descriptors\n", __func__);
+ return;
+ }
+
+ if (get_unaligned_be16(&buffer[10]) < 1) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: Need 1 or more segment descriptor\n", __func__);
+ return;
+ }
+
+ if (len - 40 != buffer[43]) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: Buffer len and descriptor count mismatch " \
+ "(%u vs. %u)\n", __func__, len - 40, buffer[43]);
+ return;
+ }
+
+ for (i = 44 ; i < len + 4 ; i++) {
+ if (buffer[i] == 0x02)
+ b2b_desc = true;
+
+ if (buffer[i] == 0xe4)
+ id_desc = true;
+ }
+
+ if (!b2b_desc) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: No block 2 block descriptor (0x02)\n",
+ __func__);
+ return;
+ }
+
+ if (!id_desc) {
+ sd_printk(KERN_ERR, sdkp,
+ "%s: No identification descriptor (0xE4)\n",
+ __func__);
+ return;
+ }
+
+ sdkp->max_copy_blocks = get_unaligned_be32(&buffer[16])
+ >> ilog2(sdev->sector_size);
+ sd_config_copy(sdkp);
+}
+
static int sd_try_extended_inquiry(struct scsi_device *sdp)
{
/* Attempt VPD inquiry if the device blacklist explicitly calls
@@ -2810,6 +3074,7 @@ static int sd_revalidate_disk(struct gen
sd_read_cache_type(sdkp, buffer);
sd_read_app_tag_own(sdkp, buffer);
sd_read_write_same(sdkp, buffer);
+ sd_read_copy_operations(sdkp, buffer);
}

sdkp->first_scan = 0;
Index: linux-3.18-rc1/drivers/scsi/sd.h
===================================================================
--- linux-3.18-rc1.orig/drivers/scsi/sd.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/drivers/scsi/sd.h 2014-10-21 01:04:22.000000000 +0200
@@ -19,6 +19,7 @@
*/
#define SD_FLUSH_TIMEOUT_MULTIPLIER 2
#define SD_WRITE_SAME_TIMEOUT (120 * HZ)
+#define SD_COPY_TIMEOUT (120 * HZ)

/*
* Number of allowed retries
@@ -48,6 +49,8 @@ enum {
SD_MAX_XFER_BLOCKS = 0xffffffff,
SD_MAX_WS10_BLOCKS = 0xffff,
SD_MAX_WS16_BLOCKS = 0x7fffff,
+ SD_MAX_CSD2_BLOCKS = 0xffff,
+ SD_MAX_COPY_BLOCKS = 0xffffffff,
};

enum {
@@ -69,6 +72,7 @@ struct scsi_disk {
u32 max_xfer_blocks;
u32 max_ws_blocks;
u32 max_unmap_blocks;
+ u32 max_copy_blocks;
u32 unmap_granularity;
u32 unmap_alignment;
u32 index;
Index: linux-3.18-rc1/include/linux/bio.h
===================================================================
--- linux-3.18-rc1.orig/include/linux/bio.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/include/linux/bio.h 2014-10-21 01:04:22.000000000 +0200
@@ -106,7 +106,7 @@ static inline bool bio_has_data(struct b
{
if (bio &&
bio->bi_iter.bi_size &&
- !(bio->bi_rw & REQ_DISCARD))
+ !(bio->bi_rw & (REQ_DISCARD | REQ_COPY)))
return true;

return false;
@@ -260,8 +260,8 @@ static inline unsigned bio_segments(stru
struct bvec_iter iter;

/*
- * We special case discard/write same, because they interpret bi_size
- * differently:
+ * We special case discard/write same/copy, because they
+ * interpret bi_size differently:
*/

if (bio->bi_rw & REQ_DISCARD)
@@ -270,6 +270,9 @@ static inline unsigned bio_segments(stru
if (bio->bi_rw & REQ_WRITE_SAME)
return 1;

+ if (bio->bi_rw & REQ_COPY)
+ return 1;
+
bio_for_each_segment(bv, bio, iter)
segs++;

Index: linux-3.18-rc1/include/linux/blk_types.h
===================================================================
--- linux-3.18-rc1.orig/include/linux/blk_types.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/include/linux/blk_types.h 2014-10-21 01:04:30.000000000 +0200
@@ -39,6 +39,11 @@ struct bvec_iter {
current bvec */
};

+struct bio_copy {
+ struct block_device *bic_bdev;
+ sector_t bic_sector;
+};
+
/*
* main unit of I/O for the block layer and lower layers (ie drivers and
* stacking drivers)
@@ -83,6 +88,7 @@ struct bio {
struct bio_integrity_payload *bi_integrity; /* data integrity */
#endif
};
+ struct bio_copy *bi_copy; /* TODO, use bi_integrity */

unsigned short bi_vcnt; /* how many bio_vec's */

@@ -160,6 +166,7 @@ enum rq_flag_bits {
__REQ_DISCARD, /* request to discard sectors */
__REQ_SECURE, /* secure discard (used with __REQ_DISCARD) */
__REQ_WRITE_SAME, /* write same block many times */
+ __REQ_COPY, /* copy block range */

__REQ_NOIDLE, /* don't anticipate more IO after this one */
__REQ_INTEGRITY, /* I/O includes block integrity payload */
@@ -202,6 +209,7 @@ enum rq_flag_bits {
#define REQ_PRIO (1ULL << __REQ_PRIO)
#define REQ_DISCARD (1ULL << __REQ_DISCARD)
#define REQ_WRITE_SAME (1ULL << __REQ_WRITE_SAME)
+#define REQ_COPY (1ULL << __REQ_COPY)
#define REQ_NOIDLE (1ULL << __REQ_NOIDLE)
#define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)

@@ -210,14 +218,15 @@ enum rq_flag_bits {
#define REQ_COMMON_MASK \
(REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | \
REQ_DISCARD | REQ_WRITE_SAME | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | \
- REQ_SECURE | REQ_INTEGRITY)
+ REQ_SECURE | REQ_INTEGRITY | REQ_COPY)
#define REQ_CLONE_MASK REQ_COMMON_MASK

-#define BIO_NO_ADVANCE_ITER_MASK (REQ_DISCARD|REQ_WRITE_SAME)
+#define BIO_NO_ADVANCE_ITER_MASK (REQ_DISCARD|REQ_WRITE_SAME|REQ_COPY)

/* This mask is used for both bio and request merge checking */
#define REQ_NOMERGE_FLAGS \
- (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA)
+ (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA | \
+ REQ_COPY)

#define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
#define REQ_THROTTLED (1ULL << __REQ_THROTTLED)
Index: linux-3.18-rc1/include/linux/blkdev.h
===================================================================
--- linux-3.18-rc1.orig/include/linux/blkdev.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/include/linux/blkdev.h 2014-10-21 01:04:22.000000000 +0200
@@ -291,6 +291,7 @@ struct queue_limits {
unsigned int io_opt;
unsigned int max_discard_sectors;
unsigned int max_write_same_sectors;
+ unsigned int max_copy_sectors;
unsigned int discard_granularity;
unsigned int discard_alignment;

@@ -1009,6 +1010,8 @@ extern void blk_queue_max_discard_sector
unsigned int max_discard_sectors);
extern void blk_queue_max_write_same_sectors(struct request_queue *q,
unsigned int max_write_same_sectors);
+extern void blk_queue_max_copy_sectors(struct request_queue *q,
+ unsigned int max_copy_sectors);
extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
extern void blk_queue_alignment_offset(struct request_queue *q,
@@ -1167,6 +1170,8 @@ extern int blkdev_issue_discard(struct b
sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct page *page);
+extern int blkdev_issue_copy(struct block_device *, sector_t,
+ struct block_device *, sector_t, unsigned int, gfp_t);
extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask);
static inline int sb_issue_discard(struct super_block *sb, sector_t block,
@@ -1365,6 +1370,16 @@ static inline unsigned int bdev_write_sa
return 0;
}

+static inline unsigned int bdev_copy_offload(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return q->limits.max_copy_sectors;
+
+ return 0;
+}
+
static inline int queue_dma_alignment(struct request_queue *q)
{
return q ? q->dma_alignment : 511;
Index: linux-3.18-rc1/include/scsi/scsi_device.h
===================================================================
--- linux-3.18-rc1.orig/include/scsi/scsi_device.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/include/scsi/scsi_device.h 2014-10-21 01:04:22.000000000 +0200
@@ -119,6 +119,8 @@ struct scsi_device {
unsigned char *vpd_pg83;
int vpd_pg80_len;
unsigned char *vpd_pg80;
+ unsigned char naa_len;
+ unsigned char *naa;
unsigned char current_tag; /* current tag */
struct scsi_target *sdev_target; /* used only for single_lun */

@@ -150,6 +152,7 @@ struct scsi_device {
unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
unsigned no_report_opcodes:1; /* no REPORT SUPPORTED OPERATION CODES */
unsigned no_write_same:1; /* no WRITE SAME command */
+ unsigned no_copy:1; /* no copy offload */
unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
unsigned skip_ms_page_8:1; /* do not use MODE SENSE page 0x08 */
unsigned skip_ms_page_3f:1; /* do not use MODE SENSE page 0x3f */
Index: linux-3.18-rc1/include/uapi/linux/fs.h
===================================================================
--- linux-3.18-rc1.orig/include/uapi/linux/fs.h 2014-10-21 01:04:15.000000000 +0200
+++ linux-3.18-rc1/include/uapi/linux/fs.h 2014-10-21 01:04:22.000000000 +0200
@@ -149,6 +149,7 @@ struct inodes_stat_t {
#define BLKSECDISCARD _IO(0x12,125)
#define BLKROTATIONAL _IO(0x12,126)
#define BLKZEROOUT _IO(0x12,127)
+#define BLKCOPY _IO(0x12,128)

#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
#define FIBMAP _IO(0x00,1) /* bmap access */
Index: linux-3.18-rc1/block/compat_ioctl.c
===================================================================
--- linux-3.18-rc1.orig/block/compat_ioctl.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/compat_ioctl.c 2014-10-21 01:04:22.000000000 +0200
@@ -697,6 +697,7 @@ long compat_blkdev_ioctl(struct file *fi
* but we call blkdev_ioctl, which gets the lock for us
*/
case BLKRRPART:
+ case BLKCOPY:
return blkdev_ioctl(bdev, mode, cmd,
(unsigned long)compat_ptr(arg));
case BLKBSZSET_32:
Index: linux-3.18-rc1/block/bio.c
===================================================================
--- linux-3.18-rc1.orig/block/bio.c 2014-10-21 01:04:14.000000000 +0200
+++ linux-3.18-rc1/block/bio.c 2014-10-21 01:04:22.000000000 +0200
@@ -239,6 +239,8 @@ static void __bio_free(struct bio *bio)
{
bio_disassociate_task(bio);

+ kfree(bio->bi_copy);
+
if (bio_integrity(bio))
bio_integrity_free(bio);
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/