diff options
Diffstat (limited to 'block/block-copy.c')
| -rw-r--r-- | block/block-copy.c | 118 |
1 files changed, 51 insertions, 67 deletions
diff --git a/block/block-copy.c b/block/block-copy.c index cd45b373a9..845b2423dc 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -126,79 +126,64 @@ void block_copy_set_callbacks( } /* - * Copy range to target with a bounce buffer and return the bytes copied. If - * error occurred, return a negative error number + * block_copy_do_copy + * + * Do copy of cluser-aligned chunk. @end is allowed to exceed s->len only to + * cover last cluster when s->len is not aligned to clusters. + * + * No sync here: nor bitmap neighter intersecting requests handling, only copy. + * + * Returns 0 on success. */ -static int coroutine_fn block_copy_with_bounce_buffer(BlockCopyState *s, - int64_t start, - int64_t end, - bool *error_is_read) +static int coroutine_fn block_copy_do_copy(BlockCopyState *s, + int64_t start, int64_t end, + bool *error_is_read) { int ret; - int nbytes; - void *bounce_buffer = qemu_blockalign(s->source->bs, s->cluster_size); + int nbytes = MIN(end, s->len) - start; + void *bounce_buffer = NULL; assert(QEMU_IS_ALIGNED(start, s->cluster_size)); - bdrv_reset_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); - nbytes = MIN(s->cluster_size, s->len - start); + assert(QEMU_IS_ALIGNED(end, s->cluster_size)); + assert(end < s->len || end == QEMU_ALIGN_UP(s->len, s->cluster_size)); + + if (s->use_copy_range) { + ret = bdrv_co_copy_range(s->source, start, s->target, start, nbytes, + 0, s->write_flags); + if (ret < 0) { + trace_block_copy_copy_range_fail(s, start, ret); + s->use_copy_range = false; + /* Fallback to read+write with allocated buffer */ + } else { + goto out; + } + } + + bounce_buffer = qemu_blockalign(s->source->bs, nbytes); ret = bdrv_co_pread(s->source, start, nbytes, bounce_buffer, 0); if (ret < 0) { - trace_block_copy_with_bounce_buffer_read_fail(s, start, ret); + trace_block_copy_read_fail(s, start, ret); if (error_is_read) { *error_is_read = true; } - goto fail; + goto out; } ret = bdrv_co_pwrite(s->target, start, nbytes, bounce_buffer, s->write_flags); if (ret < 0) { - trace_block_copy_with_bounce_buffer_write_fail(s, start, ret); + trace_block_copy_write_fail(s, start, ret); if (error_is_read) { *error_is_read = false; } - goto fail; + goto out; } +out: qemu_vfree(bounce_buffer); - return nbytes; -fail: - qemu_vfree(bounce_buffer); - bdrv_set_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); return ret; - -} - -/* - * Copy range to target and return the bytes copied. If error occurred, return a - * negative error number. - */ -static int coroutine_fn block_copy_with_offload(BlockCopyState *s, - int64_t start, - int64_t end) -{ - int ret; - int nr_clusters; - int nbytes; - - assert(QEMU_IS_ALIGNED(s->copy_range_size, s->cluster_size)); - assert(QEMU_IS_ALIGNED(start, s->cluster_size)); - nbytes = MIN(s->copy_range_size, MIN(end, s->len) - start); - nr_clusters = DIV_ROUND_UP(nbytes, s->cluster_size); - bdrv_reset_dirty_bitmap(s->copy_bitmap, start, - s->cluster_size * nr_clusters); - ret = bdrv_co_copy_range(s->source, start, s->target, start, nbytes, - 0, s->write_flags); - if (ret < 0) { - trace_block_copy_with_offload_fail(s, start, ret); - bdrv_set_dirty_bitmap(s->copy_bitmap, start, - s->cluster_size * nr_clusters); - return ret; - } - - return nbytes; } /* @@ -294,7 +279,7 @@ int coroutine_fn block_copy(BlockCopyState *s, block_copy_inflight_req_begin(s, &req, start, end); while (start < end) { - int64_t dirty_end; + int64_t next_zero, chunk_end; if (!bdrv_dirty_bitmap_get(s->copy_bitmap, start)) { trace_block_copy_skip(s, start); @@ -302,10 +287,15 @@ int coroutine_fn block_copy(BlockCopyState *s, continue; /* already copied */ } - dirty_end = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start, - (end - start)); - if (dirty_end < 0) { - dirty_end = end; + chunk_end = MIN(end, start + (s->use_copy_range ? + s->copy_range_size : s->cluster_size)); + + next_zero = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start, + chunk_end - start); + if (next_zero >= 0) { + assert(next_zero > start); /* start is dirty */ + assert(next_zero < chunk_end); /* no need to do MIN() */ + chunk_end = next_zero; } if (s->skip_unallocated) { @@ -316,27 +306,21 @@ int coroutine_fn block_copy(BlockCopyState *s, continue; } /* Clamp to known allocated region */ - dirty_end = MIN(dirty_end, start + status_bytes); + chunk_end = MIN(chunk_end, start + status_bytes); } trace_block_copy_process(s, start); - if (s->use_copy_range) { - ret = block_copy_with_offload(s, start, dirty_end); - if (ret < 0) { - s->use_copy_range = false; - } - } - if (!s->use_copy_range) { - ret = block_copy_with_bounce_buffer(s, start, dirty_end, - error_is_read); - } + bdrv_reset_dirty_bitmap(s->copy_bitmap, start, chunk_end - start); + + ret = block_copy_do_copy(s, start, chunk_end, error_is_read); if (ret < 0) { + bdrv_set_dirty_bitmap(s->copy_bitmap, start, chunk_end - start); break; } - start += ret; - s->progress_bytes_callback(ret, s->progress_opaque); + s->progress_bytes_callback(chunk_end - start, s->progress_opaque); + start = chunk_end; ret = 0; } |