Re: [PATCH v2 5/7] block/block-copy: rename start to offset in interfaces

[Andrey Shinkevich]

On 27/11/2019 21:08, Vladimir Sementsov-Ogievskiy wrote:
> offset/bytes pair is more usual naming in block layer, let's use it.

more common ... than start/end (or start/bytes) ...

> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> ---
>   include/block/block-copy.h |  2 +-
>   block/block-copy.c         | 80 +++++++++++++++++++-------------------
>   2 files changed, 41 insertions(+), 41 deletions(-)
> 
> diff --git a/include/block/block-copy.h b/include/block/block-copy.h
> index 7321b3d305..d96b097267 100644
> --- a/include/block/block-copy.h
> +++ b/include/block/block-copy.h
> @@ -19,7 +19,7 @@
>   #include "qemu/co-shared-resource.h"
>   
>   typedef struct BlockCopyInFlightReq {
> -    int64_t start;
> +    int64_t offset;
>       int64_t bytes;
>       QLIST_ENTRY(BlockCopyInFlightReq) list;
>       CoQueue wait_queue; /* coroutines blocked on this request */
> diff --git a/block/block-copy.c b/block/block-copy.c
> index cc273b6cb8..20068cd699 100644
> --- a/block/block-copy.c
> +++ b/block/block-copy.c
> @@ -25,13 +25,13 @@
>   #define BLOCK_COPY_MAX_MEM (128 * MiB)
>   
>   static BlockCopyInFlightReq *block_copy_find_inflight_req(BlockCopyState *s,
> -                                                          int64_t start,
> +                                                          int64_t offset,
>                                                             int64_t bytes)
>   {
>       BlockCopyInFlightReq *req;
>   
>       QLIST_FOREACH(req, &s->inflight_reqs, list) {
> -        if (start + bytes > req->start && start < req->start + req->bytes) {
> +        if (offset + bytes > req->offset && offset < req->offset + 
> req->bytes) {
>               return req;
>           }
>       }
> @@ -40,21 +40,21 @@ static BlockCopyInFlightReq 
> *block_copy_find_inflight_req(BlockCopyState *s,
>   }
>   
>   static void coroutine_fn block_copy_wait_inflight_reqs(BlockCopyState *s,
> -                                                       int64_t start,
> +                                                       int64_t offset,
>                                                          int64_t bytes)
>   {
>       BlockCopyInFlightReq *req;
>   
> -    while ((req = block_copy_find_inflight_req(s, start, bytes))) {
> +    while ((req = block_copy_find_inflight_req(s, offset, bytes))) {
>           qemu_co_queue_wait(&req->wait_queue, NULL);
>       }
>   }
>   
>   static void block_copy_inflight_req_begin(BlockCopyState *s,
>                                             BlockCopyInFlightReq *req,
> -                                          int64_t start, int64_t bytes)
> +                                          int64_t offset, int64_t bytes)
>   {
> -    req->start = start;
> +    req->offset = offset;
>       req->bytes = bytes;
>       qemu_co_queue_init(&req->wait_queue);
>       QLIST_INSERT_HEAD(&s->inflight_reqs, req, list);
> @@ -158,24 +158,24 @@ void block_copy_set_callbacks(
>    * Returns 0 on success.
>    */
>   static int coroutine_fn block_copy_do_copy(BlockCopyState *s,
> -                                           int64_t start, int64_t bytes,
> +                                           int64_t offset, int64_t bytes,
>                                              bool zeroes, bool *error_is_read)
>   {
>       int ret;
> -    int nbytes = MIN(start + bytes, s->len) - start;
> +    int nbytes = MIN(offset + bytes, s->len) - offset;
>       void *bounce_buffer = NULL;
>   
> -    assert(start >= 0 && bytes > 0 && INT64_MAX - start >= bytes);
> -    assert(QEMU_IS_ALIGNED(start, s->cluster_size));
> +    assert(offset >= 0 && bytes > 0 && INT64_MAX - offset >= bytes);
> +    assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
>       assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
> -    assert(start + bytes <= s->len ||
> -           start + bytes == QEMU_ALIGN_UP(s->len, s->cluster_size));
> +    assert(offset + bytes <= s->len ||
> +           offset + bytes == QEMU_ALIGN_UP(s->len, s->cluster_size));
>   
>       if (zeroes) {
> -        ret = bdrv_co_pwrite_zeroes(s->target, start, nbytes, s->write_flags 
> &
> +        ret = bdrv_co_pwrite_zeroes(s->target, offset, nbytes, 
> s->write_flags &
>                                       ~BDRV_REQ_WRITE_COMPRESSED);
>           if (ret < 0) {
> -            trace_block_copy_write_zeroes_fail(s, start, ret);
> +            trace_block_copy_write_zeroes_fail(s, offset, ret);
>               if (error_is_read) {
>                   *error_is_read = false;
>               }
> @@ -184,10 +184,10 @@ static int coroutine_fn 
> block_copy_do_copy(BlockCopyState *s,
>       }
>   
>       if (s->use_copy_range) {
> -        ret = bdrv_co_copy_range(s->source, start, s->target, start, nbytes,
> +        ret = bdrv_co_copy_range(s->source, offset, s->target, offset, 
> nbytes,
>                                    0, s->write_flags);
>           if (ret < 0) {
> -            trace_block_copy_copy_range_fail(s, start, ret);
> +            trace_block_copy_copy_range_fail(s, offset, ret);
>               s->use_copy_range = false;
>               s->copy_size = MAX(s->cluster_size, BLOCK_COPY_MAX_BUFFER);
>               /* Fallback to read+write with allocated buffer */
> @@ -221,19 +221,19 @@ static int coroutine_fn 
> block_copy_do_copy(BlockCopyState *s,
>   
>       bounce_buffer = qemu_blockalign(s->source->bs, nbytes);
>   
> -    ret = bdrv_co_pread(s->source, start, nbytes, bounce_buffer, 0);
> +    ret = bdrv_co_pread(s->source, offset, nbytes, bounce_buffer, 0);
>       if (ret < 0) {
> -        trace_block_copy_read_fail(s, start, ret);
> +        trace_block_copy_read_fail(s, offset, ret);
>           if (error_is_read) {
>               *error_is_read = true;
>           }
>           goto out;
>       }
>   
> -    ret = bdrv_co_pwrite(s->target, start, nbytes, bounce_buffer,
> +    ret = bdrv_co_pwrite(s->target, offset, nbytes, bounce_buffer,
>                            s->write_flags);
>       if (ret < 0) {
> -        trace_block_copy_write_fail(s, start, ret);
> +        trace_block_copy_write_fail(s, offset, ret);
>           if (error_is_read) {
>               *error_is_read = false;
>           }
> @@ -345,7 +345,7 @@ int64_t block_copy_reset_unallocated(BlockCopyState *s,
>   }
>   
>   int coroutine_fn block_copy(BlockCopyState *s,
> -                            int64_t start, uint64_t bytes,
> +                            int64_t offset, uint64_t bytes,
>                               bool *error_is_read)
>   {
>       int ret = 0;
> @@ -358,59 +358,59 @@ int coroutine_fn block_copy(BlockCopyState *s,
>       assert(bdrv_get_aio_context(s->source->bs) ==
>              bdrv_get_aio_context(s->target->bs));
>   
> -    assert(QEMU_IS_ALIGNED(start, s->cluster_size));
> +    assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
>       assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
>   
> -    block_copy_wait_inflight_reqs(s, start, bytes);
> -    block_copy_inflight_req_begin(s, &req, start, bytes);
> +    block_copy_wait_inflight_reqs(s, offset, bytes);
> +    block_copy_inflight_req_begin(s, &req, offset, bytes);
>   
>       while (bytes) {
>           int64_t next_zero, cur_bytes, status_bytes;
>   
> -        if (!bdrv_dirty_bitmap_get(s->copy_bitmap, start)) {
> -            trace_block_copy_skip(s, start);
> -            start += s->cluster_size;
> +        if (!bdrv_dirty_bitmap_get(s->copy_bitmap, offset)) {
> +            trace_block_copy_skip(s, offset);
> +            offset += s->cluster_size;
>               bytes -= s->cluster_size;
>               continue; /* already copied */
>           }
>   
>           cur_bytes = MIN(bytes, s->copy_size);
>   
> -        next_zero = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start,
> +        next_zero = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, offset,
>                                                   cur_bytes);
>           if (next_zero >= 0) {
> -            assert(next_zero > start); /* start is dirty */
> -            assert(next_zero < start + cur_bytes); /* no need to do MIN() */
> -            cur_bytes = next_zero - start;
> +            assert(next_zero > offset); /* offset is dirty */
> +            assert(next_zero < offset + cur_bytes); /* no need to do MIN() */
> +            cur_bytes = next_zero - offset;
>           }
>   
> -        ret = block_copy_block_status(s, start, cur_bytes, &status_bytes);
> +        ret = block_copy_block_status(s, offset, cur_bytes, &status_bytes);
>           if (s->skip_unallocated && !(ret & BDRV_BLOCK_ALLOCATED)) {
> -            bdrv_reset_dirty_bitmap(s->copy_bitmap, start, status_bytes);
> +            bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, status_bytes);
>               s->progress_reset_callback(s->progress_opaque);
> -            trace_block_copy_skip_range(s, start, status_bytes);
> -            start += status_bytes;
> +            trace_block_copy_skip_range(s, offset, status_bytes);
> +            offset += status_bytes;
>               bytes -= status_bytes;
>               continue;
>           }
>   
>           cur_bytes = MIN(cur_bytes, status_bytes);
>   
> -        trace_block_copy_process(s, start);
> +        trace_block_copy_process(s, offset);
>   
> -        bdrv_reset_dirty_bitmap(s->copy_bitmap, start, cur_bytes);
> +        bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, cur_bytes);
>   
>           co_get_from_shres(s->mem, cur_bytes);
> -        ret = block_copy_do_copy(s, start, cur_bytes, ret & BDRV_BLOCK_ZERO,
> +        ret = block_copy_do_copy(s, offset, cur_bytes, ret & BDRV_BLOCK_ZERO,
>                                    error_is_read);
>           co_put_to_shres(s->mem, cur_bytes);
>           if (ret < 0) {
> -            bdrv_set_dirty_bitmap(s->copy_bitmap, start, cur_bytes);
> +            bdrv_set_dirty_bitmap(s->copy_bitmap, offset, cur_bytes);
>               break;
>           }
>   
>           s->progress_bytes_callback(cur_bytes, s->progress_opaque);
> -        start += cur_bytes;
> +        offset += cur_bytes;
>           bytes -= cur_bytes;
>       }
>   
> 

Reviewed-by: Andrey Shinkevich <address@hidden>
-- 
With the best regards,
Andrey Shinkevich