7  * later.  See the COPYING file in the top-level directory.
11 #include "block/block_int-common.h"
13 #include "system/block-backend.h"
17 #include "qapi/qapi-types-block.h"
20  * Read the non-zeroes parts of @blk into @buf
23  * the non-zeroes block into @buf.
25  * Return 0 on success, non-zero on error.
34         bytes = MIN(size - offset, BDRV_REQUEST_MAX_BYTES);  in blk_pread_nonzeroes()
56  * On success, return true.
57  * On failure, store an error through @errp and return false.
59  * This function not intended for actual block devices, which read on
60  * demand.  It's for things like memory devices that (ab)use a block
76         error_setg_errno(errp, -blk_len,  in blk_check_size_and_read_all()
93      * block device and read only on demand.  in blk_check_size_and_read_all()
99         error_setg_errno(errp, -ret, "can't read %s block backend"  in blk_check_size_and_read_all()
110     BlockBackend *blk = conf->blk;  in blkconf_blocksizes()
116     switch (conf->backend_defaults) {  in blkconf_blocksizes()
138     if (!conf->physical_block_size) {  in blkconf_blocksizes()
140            conf->physical_block_size = blocksizes.phys;  in blkconf_blocksizes()
142             conf->physical_block_size = BDRV_SECTOR_SIZE;  in blkconf_blocksizes()
145     if (!conf->logical_block_size) {  in blkconf_blocksizes()
147             conf->logical_block_size = blocksizes.log;  in blkconf_blocksizes()
149             conf->logical_block_size = BDRV_SECTOR_SIZE;  in blkconf_blocksizes()
153         if (!conf->opt_io_size) {  in blkconf_blocksizes()
154             conf->opt_io_size = bs->bl.opt_transfer;  in blkconf_blocksizes()
156         if (conf->discard_granularity == -1) {  in blkconf_blocksizes()
157             if (bs->bl.pdiscard_alignment) {  in blkconf_blocksizes()
158                 conf->discard_granularity = bs->bl.pdiscard_alignment;  in blkconf_blocksizes()
159             } else if (bs->bl.request_alignment != 1) {  in blkconf_blocksizes()
160                 conf->discard_granularity = bs->bl.request_alignment;  in blkconf_blocksizes()
165     if (conf->logical_block_size > conf->physical_block_size) {  in blkconf_blocksizes()
171     if (!QEMU_IS_ALIGNED(conf->min_io_size, conf->logical_block_size)) {  in blkconf_blocksizes()
178      * all devices which support min_io_size (scsi and virtio-blk) expose it to  in blkconf_blocksizes()
181     if (conf->min_io_size / conf->logical_block_size > UINT16_MAX) {  in blkconf_blocksizes()
187     if (!QEMU_IS_ALIGNED(conf->opt_io_size, conf->logical_block_size)) {  in blkconf_blocksizes()
193     if (conf->discard_granularity != -1 &&  in blkconf_blocksizes()
194         !QEMU_IS_ALIGNED(conf->discard_granularity,  in blkconf_blocksizes()
195                          conf->logical_block_size)) {  in blkconf_blocksizes()
207     BlockBackend *blk = conf->blk;  in blkconf_apply_backend_options()
222     if (conf->share_rw) {  in blkconf_apply_backend_options()
231     switch (conf->wce) {  in blkconf_apply_backend_options()
239     rerror = conf->rerror;  in blkconf_apply_backend_options()
244     werror = conf->werror;  in blkconf_apply_backend_options()
252     block_acct_setup(blk_get_stats(blk), conf->account_invalid,  in blkconf_apply_backend_options()
253                      conf->account_failed);  in blkconf_apply_backend_options()
261     if (!conf->cyls && !conf->heads && !conf->secs) {  in blkconf_geometry()
262         hd_geometry_guess(conf->blk,  in blkconf_geometry()
263                           &conf->cyls, &conf->heads, &conf->secs,  in blkconf_geometry()
266         *ptrans = hd_bios_chs_auto_trans(conf->cyls, conf->heads, conf->secs);  in blkconf_geometry()
268     if (conf->cyls || conf->heads || conf->secs) {  in blkconf_geometry()
269         if (conf->cyls < 1 || conf->cyls > cyls_max) {  in blkconf_geometry()
273         if (conf->heads < 1 || conf->heads > heads_max) {  in blkconf_geometry()
277         if (conf->secs < 1 || conf->secs > secs_max) {  in blkconf_geometry()