Add new BLKCOPY ioctl that offloads copying of one or more sources ranges
to one or more destination in a device. COPY ioctl accepts a 'copy_range'
structure that contains no of range, a reserved field , followed by an
array of ranges. Each source range is represented by 'range_entry' that
contains source start offset, destination start offset and length of
source ranges (in bytes)

Signed-off-by: Nitesh Shetty <nj.she...@samsung.com>
Signed-off-by: Arnav Dawn <arnav.d...@samsung.com>
---
 block/ioctl.c           | 37 +++++++++++++++++++++++++++++++++++++
 include/uapi/linux/fs.h |  9 +++++++++
 2 files changed, 46 insertions(+)

diff --git a/block/ioctl.c b/block/ioctl.c
index 4a86340133e4..d77f6143287e 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -124,6 +124,41 @@ static int blk_ioctl_discard(struct block_device *bdev, 
fmode_t mode,
        return err;
 }
 
+static int blk_ioctl_copy(struct block_device *bdev, fmode_t mode,
+               unsigned long arg)
+{
+       struct copy_range crange, *ranges;
+       size_t payload_size = 0;
+       int ret;
+
+       if (!(mode & FMODE_WRITE))
+               return -EBADF;
+
+       if (copy_from_user(&crange, (void __user *)arg, sizeof(crange)))
+               return -EFAULT;
+
+       if (unlikely(!crange.nr_range || crange.reserved || crange.nr_range >= 
MAX_COPY_NR_RANGE))
+               return -EINVAL;
+
+       payload_size = (crange.nr_range * sizeof(struct range_entry)) + 
sizeof(crange);
+
+       ranges = kmalloc(payload_size, GFP_KERNEL);
+       if (!ranges)
+               return -ENOMEM;
+
+       if (copy_from_user(ranges, (void __user *)arg, payload_size)) {
+               ret = -EFAULT;
+               goto out;
+       }
+
+       ret = blkdev_issue_copy(bdev, ranges->nr_range, ranges->range_list, 
bdev, GFP_KERNEL, 0);
+       if (copy_to_user((void __user *)arg, ranges, payload_size))
+               ret = -EFAULT;
+out:
+       kfree(ranges);
+       return ret;
+}
+
 static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
                unsigned long arg)
 {
@@ -455,6 +490,8 @@ static int blkdev_common_ioctl(struct block_device *bdev, 
fmode_t mode,
        case BLKSECDISCARD:
                return blk_ioctl_discard(bdev, mode, arg,
                                BLKDEV_DISCARD_SECURE);
+       case BLKCOPY:
+               return blk_ioctl_copy(bdev, mode, arg);
        case BLKZEROOUT:
                return blk_ioctl_zeroout(bdev, mode, arg);
        case BLKGETDISKSEQ:
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 55bca8f6e8ed..190911ea4311 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -78,6 +78,14 @@ struct range_entry {
        __u64 comp_len;
 };
 
+struct copy_range {
+       __u64 nr_range;
+       __u64 reserved;
+
+       /* Range_list always must be at the end */
+       struct range_entry range_list[];
+};
+
 /* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */
 #define FILE_DEDUPE_RANGE_SAME         0
 #define FILE_DEDUPE_RANGE_DIFFERS      1
@@ -199,6 +207,7 @@ struct fsxattr {
 #define BLKROTATIONAL _IO(0x12,126)
 #define BLKZEROOUT _IO(0x12,127)
 #define BLKGETDISKSEQ _IOR(0x12,128,__u64)
+#define BLKCOPY _IOWR(0x12, 129, struct copy_range)
 /*
  * A jump here: 130-136 are reserved for zoned block devices
  * (see uapi/linux/blkzoned.h)
-- 
2.30.0-rc0


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