From a73466fbad6d48ba356940474cd72da602373304 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Wed, 27 Sep 2017 13:53:38 +0100 Subject: [PATCH] block: convert crypto driver to bdrv_co_preadv|pwritev Make the crypto driver implement the bdrv_co_preadv|pwritev callbacks, and also use bdrv_co_preadv|pwritev for I/O with the protocol driver beneath. This replaces sector based I/O with byte based I/O, and allows us to stop assuming the physical sector size matches the encryption sector size. Signed-off-by: Daniel P. Berrange Message-id: 20170927125340.12360-5-berrange@redhat.com Reviewed-by: Eric Blake Reviewed-by: Max Reitz Signed-off-by: Max Reitz --- block/crypto.c | 106 +++++++++++++++++++++++++++++---------------------------- 1 file changed, 54 insertions(+), 52 deletions(-) diff --git a/block/crypto.c b/block/crypto.c index 61f5d77bc0..965c173b01 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -387,18 +387,23 @@ static void block_crypto_close(BlockDriverState *bs) #define BLOCK_CRYPTO_MAX_IO_SIZE (1024 * 1024) static coroutine_fn int -block_crypto_co_readv(BlockDriverState *bs, int64_t sector_num, - int remaining_sectors, QEMUIOVector *qiov) +block_crypto_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) { BlockCrypto *crypto = bs->opaque; - int cur_nr_sectors; /* number of sectors in current iteration */ + uint64_t cur_bytes; /* number of bytes in current iteration */ uint64_t bytes_done = 0; uint8_t *cipher_data = NULL; QEMUIOVector hd_qiov; int ret = 0; - uint64_t payload_offset = - qcrypto_block_get_payload_offset(crypto->block) / 512; - assert(payload_offset < (INT64_MAX / 512)); + uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block); + uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block); + uint64_t sector_num = offset / sector_size; + + assert(!flags); + assert(payload_offset < INT64_MAX); + assert(QEMU_IS_ALIGNED(offset, sector_size)); + assert(QEMU_IS_ALIGNED(bytes, sector_size)); qemu_iovec_init(&hd_qiov, qiov->niov); @@ -413,37 +418,29 @@ block_crypto_co_readv(BlockDriverState *bs, int64_t sector_num, goto cleanup; } - while (remaining_sectors) { - cur_nr_sectors = remaining_sectors; - - if (cur_nr_sectors > (BLOCK_CRYPTO_MAX_IO_SIZE / 512)) { - cur_nr_sectors = (BLOCK_CRYPTO_MAX_IO_SIZE / 512); - } + while (bytes) { + cur_bytes = MIN(bytes, BLOCK_CRYPTO_MAX_IO_SIZE); qemu_iovec_reset(&hd_qiov); - qemu_iovec_add(&hd_qiov, cipher_data, cur_nr_sectors * 512); + qemu_iovec_add(&hd_qiov, cipher_data, cur_bytes); - ret = bdrv_co_readv(bs->file, - payload_offset + sector_num, - cur_nr_sectors, &hd_qiov); + ret = bdrv_co_preadv(bs->file, payload_offset + offset + bytes_done, + cur_bytes, &hd_qiov, 0); if (ret < 0) { goto cleanup; } - if (qcrypto_block_decrypt(crypto->block, - sector_num, - cipher_data, cur_nr_sectors * 512, - NULL) < 0) { + if (qcrypto_block_decrypt(crypto->block, sector_num, cipher_data, + cur_bytes, NULL) < 0) { ret = -EIO; goto cleanup; } - qemu_iovec_from_buf(qiov, bytes_done, - cipher_data, cur_nr_sectors * 512); + qemu_iovec_from_buf(qiov, bytes_done, cipher_data, cur_bytes); - remaining_sectors -= cur_nr_sectors; - sector_num += cur_nr_sectors; - bytes_done += cur_nr_sectors * 512; + sector_num += cur_bytes / sector_size; + bytes -= cur_bytes; + bytes_done += cur_bytes; } cleanup: @@ -455,18 +452,23 @@ block_crypto_co_readv(BlockDriverState *bs, int64_t sector_num, static coroutine_fn int -block_crypto_co_writev(BlockDriverState *bs, int64_t sector_num, - int remaining_sectors, QEMUIOVector *qiov) +block_crypto_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) { BlockCrypto *crypto = bs->opaque; - int cur_nr_sectors; /* number of sectors in current iteration */ + uint64_t cur_bytes; /* number of bytes in current iteration */ uint64_t bytes_done = 0; uint8_t *cipher_data = NULL; QEMUIOVector hd_qiov; int ret = 0; - uint64_t payload_offset = - qcrypto_block_get_payload_offset(crypto->block) / 512; - assert(payload_offset < (INT64_MAX / 512)); + uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block); + uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block); + uint64_t sector_num = offset / sector_size; + + assert(!flags); + assert(payload_offset < INT64_MAX); + assert(QEMU_IS_ALIGNED(offset, sector_size)); + assert(QEMU_IS_ALIGNED(bytes, sector_size)); qemu_iovec_init(&hd_qiov, qiov->niov); @@ -481,37 +483,29 @@ block_crypto_co_writev(BlockDriverState *bs, int64_t sector_num, goto cleanup; } - while (remaining_sectors) { - cur_nr_sectors = remaining_sectors; + while (bytes) { + cur_bytes = MIN(bytes, BLOCK_CRYPTO_MAX_IO_SIZE); - if (cur_nr_sectors > (BLOCK_CRYPTO_MAX_IO_SIZE / 512)) { - cur_nr_sectors = (BLOCK_CRYPTO_MAX_IO_SIZE / 512); - } - - qemu_iovec_to_buf(qiov, bytes_done, - cipher_data, cur_nr_sectors * 512); + qemu_iovec_to_buf(qiov, bytes_done, cipher_data, cur_bytes); - if (qcrypto_block_encrypt(crypto->block, - sector_num, - cipher_data, cur_nr_sectors * 512, - NULL) < 0) { + if (qcrypto_block_encrypt(crypto->block, sector_num, cipher_data, + cur_bytes, NULL) < 0) { ret = -EIO; goto cleanup; } qemu_iovec_reset(&hd_qiov); - qemu_iovec_add(&hd_qiov, cipher_data, cur_nr_sectors * 512); + qemu_iovec_add(&hd_qiov, cipher_data, cur_bytes); - ret = bdrv_co_writev(bs->file, - payload_offset + sector_num, - cur_nr_sectors, &hd_qiov); + ret = bdrv_co_pwritev(bs->file, payload_offset + offset + bytes_done, + cur_bytes, &hd_qiov, 0); if (ret < 0) { goto cleanup; } - remaining_sectors -= cur_nr_sectors; - sector_num += cur_nr_sectors; - bytes_done += cur_nr_sectors * 512; + sector_num += cur_bytes / sector_size; + bytes -= cur_bytes; + bytes_done += cur_bytes; } cleanup: @@ -521,6 +515,13 @@ block_crypto_co_writev(BlockDriverState *bs, int64_t sector_num, return ret; } +static void block_crypto_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BlockCrypto *crypto = bs->opaque; + uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block); + bs->bl.request_alignment = sector_size; /* No sub-sector I/O */ +} + static int64_t block_crypto_getlength(BlockDriverState *bs) { @@ -620,8 +621,9 @@ BlockDriver bdrv_crypto_luks = { .bdrv_truncate = block_crypto_truncate, .create_opts = &block_crypto_create_opts_luks, - .bdrv_co_readv = block_crypto_co_readv, - .bdrv_co_writev = block_crypto_co_writev, + .bdrv_refresh_limits = block_crypto_refresh_limits, + .bdrv_co_preadv = block_crypto_co_preadv, + .bdrv_co_pwritev = block_crypto_co_pwritev, .bdrv_getlength = block_crypto_getlength, .bdrv_get_info = block_crypto_get_info_luks, .bdrv_get_specific_info = block_crypto_get_specific_info_luks, -- 2.11.4.GIT