Add new BLKCOPY ioctl that offloads copying of one or more sources rangesReviewed-by: Hannes Reinecke <hare@xxxxxxx>
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)
MAX_COPY_NR_RANGE, limits the number of entries for the IOCTL and
MAX_COPY_TOTAL_LENGTH limits the total copy length, IOCTL can handle.
Example code, to issue BLKCOPY:
/* Sample example to copy three entries with [dest,src,len],
* [32768, 0, 4096] [36864, 4096, 4096] [40960,8192,4096] on same device */
int main(void)
{
int i, ret, fd;
unsigned long src = 0, dst = 32768, len = 4096;
struct copy_range *cr;
cr = (struct copy_range *)malloc(sizeof(*cr)+
(sizeof(struct range_entry)*3));
cr->nr_range = 3;
cr->reserved = 0;
for (i = 0; i< cr->nr_range; i++, src += len, dst += len) {
cr->range_list[i].dst = dst;
cr->range_list[i].src = src;
cr->range_list[i].len = len;
cr->range_list[i].comp_len = 0;
}
fd = open("/dev/nvme0n1", O_RDWR);
if (fd < 0) return 1;
ret = ioctl(fd, BLKCOPY, cr);
if (ret != 0)
printf("copy failed, ret= %d\n", ret);
for (i=0; i< cr->nr_range; i++)
if (cr->range_list[i].len != cr->range_list[i].comp_len)
printf("Partial copy for entry %d: requested %llu, completed %llu\n",
i, cr->range_list[i].len,
cr->range_list[i].comp_len);
close(fd);
free(cr);
return ret;
}
Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
Signed-off-by: Javier González <javier.gonz@xxxxxxxxxxx>
Signed-off-by: Arnav Dawn <arnav.dawn@xxxxxxxxxxx>
---
block/ioctl.c | 32 ++++++++++++++++++++++++++++++++
include/uapi/linux/fs.h | 9 +++++++++
2 files changed, 41 insertions(+)