| /* BlockDriver implementation for "raw" |
| * |
| * Copyright (C) 2010, 2013, Red Hat, Inc. |
| * Copyright (C) 2010, Blue Swirl <blauwirbel@gmail.com> |
| * Copyright (C) 2009, Anthony Liguori <aliguori@us.ibm.com> |
| * |
| * Author: |
| * Laszlo Ersek <lersek@redhat.com> |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to |
| * deal in the Software without restriction, including without limitation the |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
| * sell copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "block/block_int.h" |
| #include "qapi/error.h" |
| #include "qemu/option.h" |
| |
| static QemuOptsList raw_create_opts = { |
| .name = "raw-create-opts", |
| .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head), |
| .desc = { |
| { |
| .name = BLOCK_OPT_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Virtual disk size" |
| }, |
| { /* end of list */ } |
| } |
| }; |
| |
| static int raw_reopen_prepare(BDRVReopenState *reopen_state, |
| BlockReopenQueue *queue, Error **errp) |
| { |
| return 0; |
| } |
| |
| static int coroutine_fn raw_co_readv(BlockDriverState *bs, int64_t sector_num, |
| int nb_sectors, QEMUIOVector *qiov) |
| { |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
| return bdrv_co_readv(bs->file->bs, sector_num, nb_sectors, qiov); |
| } |
| |
| static int coroutine_fn |
| raw_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors, |
| QEMUIOVector *qiov, int flags) |
| { |
| void *buf = NULL; |
| BlockDriver *drv; |
| QEMUIOVector local_qiov; |
| int ret; |
| |
| if (bs->probed && sector_num == 0) { |
| /* As long as these conditions are true, we can't get partial writes to |
| * the probe buffer and can just directly check the request. */ |
| QEMU_BUILD_BUG_ON(BLOCK_PROBE_BUF_SIZE != 512); |
| QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != 512); |
| |
| if (nb_sectors == 0) { |
| /* qemu_iovec_to_buf() would fail, but we want to return success |
| * instead of -EINVAL in this case. */ |
| return 0; |
| } |
| |
| buf = qemu_try_blockalign(bs->file->bs, 512); |
| if (!buf) { |
| ret = -ENOMEM; |
| goto fail; |
| } |
| |
| ret = qemu_iovec_to_buf(qiov, 0, buf, 512); |
| if (ret != 512) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| drv = bdrv_probe_all(buf, 512, NULL); |
| if (drv != bs->drv) { |
| ret = -EPERM; |
| goto fail; |
| } |
| |
| /* Use the checked buffer, a malicious guest might be overwriting its |
| * original buffer in the background. */ |
| qemu_iovec_init(&local_qiov, qiov->niov + 1); |
| qemu_iovec_add(&local_qiov, buf, 512); |
| qemu_iovec_concat(&local_qiov, qiov, 512, qiov->size - 512); |
| qiov = &local_qiov; |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
| ret = bdrv_co_pwritev(bs->file->bs, sector_num * BDRV_SECTOR_SIZE, |
| nb_sectors * BDRV_SECTOR_SIZE, qiov, flags); |
| |
| fail: |
| if (qiov == &local_qiov) { |
| qemu_iovec_destroy(&local_qiov); |
| } |
| qemu_vfree(buf); |
| return ret; |
| } |
| |
| static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs, |
| int64_t sector_num, |
| int nb_sectors, int *pnum, |
| BlockDriverState **file) |
| { |
| *pnum = nb_sectors; |
| *file = bs->file->bs; |
| return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | BDRV_BLOCK_DATA | |
| (sector_num << BDRV_SECTOR_BITS); |
| } |
| |
| static int coroutine_fn raw_co_pwrite_zeroes(BlockDriverState *bs, |
| int64_t offset, int count, |
| BdrvRequestFlags flags) |
| { |
| return bdrv_co_pwrite_zeroes(bs->file->bs, offset, count, flags); |
| } |
| |
| static int coroutine_fn raw_co_discard(BlockDriverState *bs, |
| int64_t sector_num, int nb_sectors) |
| { |
| return bdrv_co_discard(bs->file->bs, sector_num, nb_sectors); |
| } |
| |
| static int64_t raw_getlength(BlockDriverState *bs) |
| { |
| return bdrv_getlength(bs->file->bs); |
| } |
| |
| static int raw_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| { |
| return bdrv_get_info(bs->file->bs, bdi); |
| } |
| |
| static void raw_refresh_limits(BlockDriverState *bs, Error **errp) |
| { |
| bs->bl = bs->file->bs->bl; |
| } |
| |
| static int raw_truncate(BlockDriverState *bs, int64_t offset) |
| { |
| return bdrv_truncate(bs->file->bs, offset); |
| } |
| |
| static int raw_media_changed(BlockDriverState *bs) |
| { |
| return bdrv_media_changed(bs->file->bs); |
| } |
| |
| static void raw_eject(BlockDriverState *bs, bool eject_flag) |
| { |
| bdrv_eject(bs->file->bs, eject_flag); |
| } |
| |
| static void raw_lock_medium(BlockDriverState *bs, bool locked) |
| { |
| bdrv_lock_medium(bs->file->bs, locked); |
| } |
| |
| static BlockAIOCB *raw_aio_ioctl(BlockDriverState *bs, |
| unsigned long int req, void *buf, |
| BlockCompletionFunc *cb, |
| void *opaque) |
| { |
| return bdrv_aio_ioctl(bs->file->bs, req, buf, cb, opaque); |
| } |
| |
| static int raw_has_zero_init(BlockDriverState *bs) |
| { |
| return bdrv_has_zero_init(bs->file->bs); |
| } |
| |
| static int raw_create(const char *filename, QemuOpts *opts, Error **errp) |
| { |
| return bdrv_create_file(filename, opts, errp); |
| } |
| |
| static int raw_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| bs->sg = bs->file->bs->sg; |
| bs->supported_write_flags = BDRV_REQ_FUA; |
| bs->supported_zero_flags = BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP; |
| |
| if (bs->probed && !bdrv_is_read_only(bs)) { |
| fprintf(stderr, |
| "WARNING: Image format was not specified for '%s' and probing " |
| "guessed raw.\n" |
| " Automatically detecting the format is dangerous for " |
| "raw images, write operations on block 0 will be restricted.\n" |
| " Specify the 'raw' format explicitly to remove the " |
| "restrictions.\n", |
| bs->file->bs->filename); |
| } |
| |
| return 0; |
| } |
| |
| static void raw_close(BlockDriverState *bs) |
| { |
| } |
| |
| static int raw_probe(const uint8_t *buf, int buf_size, const char *filename) |
| { |
| /* smallest possible positive score so that raw is used if and only if no |
| * other block driver works |
| */ |
| return 1; |
| } |
| |
| static int raw_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) |
| { |
| return bdrv_probe_blocksizes(bs->file->bs, bsz); |
| } |
| |
| static int raw_probe_geometry(BlockDriverState *bs, HDGeometry *geo) |
| { |
| return bdrv_probe_geometry(bs->file->bs, geo); |
| } |
| |
| BlockDriver bdrv_raw = { |
| .format_name = "raw", |
| .bdrv_probe = &raw_probe, |
| .bdrv_reopen_prepare = &raw_reopen_prepare, |
| .bdrv_open = &raw_open, |
| .bdrv_close = &raw_close, |
| .bdrv_create = &raw_create, |
| .bdrv_co_readv = &raw_co_readv, |
| .bdrv_co_writev_flags = &raw_co_writev_flags, |
| .bdrv_co_pwrite_zeroes = &raw_co_pwrite_zeroes, |
| .bdrv_co_discard = &raw_co_discard, |
| .bdrv_co_get_block_status = &raw_co_get_block_status, |
| .bdrv_truncate = &raw_truncate, |
| .bdrv_getlength = &raw_getlength, |
| .has_variable_length = true, |
| .bdrv_get_info = &raw_get_info, |
| .bdrv_refresh_limits = &raw_refresh_limits, |
| .bdrv_probe_blocksizes = &raw_probe_blocksizes, |
| .bdrv_probe_geometry = &raw_probe_geometry, |
| .bdrv_media_changed = &raw_media_changed, |
| .bdrv_eject = &raw_eject, |
| .bdrv_lock_medium = &raw_lock_medium, |
| .bdrv_aio_ioctl = &raw_aio_ioctl, |
| .create_opts = &raw_create_opts, |
| .bdrv_has_zero_init = &raw_has_zero_init |
| }; |
| |
| static void bdrv_raw_init(void) |
| { |
| bdrv_register(&bdrv_raw); |
| } |
| |
| block_init(bdrv_raw_init); |