diff options
author | RajithaY <rajithax.yerrumsetty@intel.com> | 2017-04-25 03:31:15 -0700 |
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committer | Rajitha Yerrumchetty <rajithax.yerrumsetty@intel.com> | 2017-05-22 06:48:08 +0000 |
commit | bb756eebdac6fd24e8919e2c43f7d2c8c4091f59 (patch) | |
tree | ca11e03542edf2d8f631efeca5e1626d211107e3 /qemu/block.c | |
parent | a14b48d18a9ed03ec191cf16b162206998a895ce (diff) |
Adding qemu as a submodule of KVMFORNFV
This Patch includes the changes to add qemu as a submodule to
kvmfornfv repo and make use of the updated latest qemu for the
execution of all testcase
Change-Id: I1280af507a857675c7f81d30c95255635667bdd7
Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
Diffstat (limited to 'qemu/block.c')
-rw-r--r-- | qemu/block.c | 3983 |
1 files changed, 0 insertions, 3983 deletions
diff --git a/qemu/block.c b/qemu/block.c deleted file mode 100644 index d4939b49b..000000000 --- a/qemu/block.c +++ /dev/null @@ -1,3983 +0,0 @@ -/* - * QEMU System Emulator block driver - * - * Copyright (c) 2003 Fabrice Bellard - * - * 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 "trace.h" -#include "block/block_int.h" -#include "block/blockjob.h" -#include "qemu/error-report.h" -#include "qemu/module.h" -#include "qapi/qmp/qerror.h" -#include "qapi/qmp/qbool.h" -#include "qapi/qmp/qjson.h" -#include "sysemu/block-backend.h" -#include "sysemu/sysemu.h" -#include "qemu/notify.h" -#include "qemu/coroutine.h" -#include "block/qapi.h" -#include "qmp-commands.h" -#include "qemu/timer.h" -#include "qapi-event.h" -#include "block/throttle-groups.h" -#include "qemu/cutils.h" -#include "qemu/id.h" - -#ifdef CONFIG_BSD -#include <sys/ioctl.h> -#include <sys/queue.h> -#ifndef __DragonFly__ -#include <sys/disk.h> -#endif -#endif - -#ifdef _WIN32 -#include <windows.h> -#endif - -#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ - -static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states = - QTAILQ_HEAD_INITIALIZER(graph_bdrv_states); - -static QTAILQ_HEAD(, BlockDriverState) all_bdrv_states = - QTAILQ_HEAD_INITIALIZER(all_bdrv_states); - -static QLIST_HEAD(, BlockDriver) bdrv_drivers = - QLIST_HEAD_INITIALIZER(bdrv_drivers); - -static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename, - const char *reference, QDict *options, int flags, - BlockDriverState *parent, - const BdrvChildRole *child_role, Error **errp); - -/* If non-zero, use only whitelisted block drivers */ -static int use_bdrv_whitelist; - -static void bdrv_close(BlockDriverState *bs); - -#ifdef _WIN32 -static int is_windows_drive_prefix(const char *filename) -{ - return (((filename[0] >= 'a' && filename[0] <= 'z') || - (filename[0] >= 'A' && filename[0] <= 'Z')) && - filename[1] == ':'); -} - -int is_windows_drive(const char *filename) -{ - if (is_windows_drive_prefix(filename) && - filename[2] == '\0') - return 1; - if (strstart(filename, "\\\\.\\", NULL) || - strstart(filename, "//./", NULL)) - return 1; - return 0; -} -#endif - -size_t bdrv_opt_mem_align(BlockDriverState *bs) -{ - if (!bs || !bs->drv) { - /* page size or 4k (hdd sector size) should be on the safe side */ - return MAX(4096, getpagesize()); - } - - return bs->bl.opt_mem_alignment; -} - -size_t bdrv_min_mem_align(BlockDriverState *bs) -{ - if (!bs || !bs->drv) { - /* page size or 4k (hdd sector size) should be on the safe side */ - return MAX(4096, getpagesize()); - } - - return bs->bl.min_mem_alignment; -} - -/* check if the path starts with "<protocol>:" */ -int path_has_protocol(const char *path) -{ - const char *p; - -#ifdef _WIN32 - if (is_windows_drive(path) || - is_windows_drive_prefix(path)) { - return 0; - } - p = path + strcspn(path, ":/\\"); -#else - p = path + strcspn(path, ":/"); -#endif - - return *p == ':'; -} - -int path_is_absolute(const char *path) -{ -#ifdef _WIN32 - /* specific case for names like: "\\.\d:" */ - if (is_windows_drive(path) || is_windows_drive_prefix(path)) { - return 1; - } - return (*path == '/' || *path == '\\'); -#else - return (*path == '/'); -#endif -} - -/* if filename is absolute, just copy it to dest. Otherwise, build a - path to it by considering it is relative to base_path. URL are - supported. */ -void path_combine(char *dest, int dest_size, - const char *base_path, - const char *filename) -{ - const char *p, *p1; - int len; - - if (dest_size <= 0) - return; - if (path_is_absolute(filename)) { - pstrcpy(dest, dest_size, filename); - } else { - p = strchr(base_path, ':'); - if (p) - p++; - else - p = base_path; - p1 = strrchr(base_path, '/'); -#ifdef _WIN32 - { - const char *p2; - p2 = strrchr(base_path, '\\'); - if (!p1 || p2 > p1) - p1 = p2; - } -#endif - if (p1) - p1++; - else - p1 = base_path; - if (p1 > p) - p = p1; - len = p - base_path; - if (len > dest_size - 1) - len = dest_size - 1; - memcpy(dest, base_path, len); - dest[len] = '\0'; - pstrcat(dest, dest_size, filename); - } -} - -void bdrv_get_full_backing_filename_from_filename(const char *backed, - const char *backing, - char *dest, size_t sz, - Error **errp) -{ - if (backing[0] == '\0' || path_has_protocol(backing) || - path_is_absolute(backing)) - { - pstrcpy(dest, sz, backing); - } else if (backed[0] == '\0' || strstart(backed, "json:", NULL)) { - error_setg(errp, "Cannot use relative backing file names for '%s'", - backed); - } else { - path_combine(dest, sz, backed, backing); - } -} - -void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz, - Error **errp) -{ - char *backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename; - - bdrv_get_full_backing_filename_from_filename(backed, bs->backing_file, - dest, sz, errp); -} - -void bdrv_register(BlockDriver *bdrv) -{ - bdrv_setup_io_funcs(bdrv); - - QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); -} - -BlockDriverState *bdrv_new_root(void) -{ - return bdrv_new(); -} - -BlockDriverState *bdrv_new(void) -{ - BlockDriverState *bs; - int i; - - bs = g_new0(BlockDriverState, 1); - QLIST_INIT(&bs->dirty_bitmaps); - for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { - QLIST_INIT(&bs->op_blockers[i]); - } - notifier_with_return_list_init(&bs->before_write_notifiers); - qemu_co_queue_init(&bs->throttled_reqs[0]); - qemu_co_queue_init(&bs->throttled_reqs[1]); - bs->refcnt = 1; - bs->aio_context = qemu_get_aio_context(); - - QTAILQ_INSERT_TAIL(&all_bdrv_states, bs, bs_list); - - return bs; -} - -BlockDriver *bdrv_find_format(const char *format_name) -{ - BlockDriver *drv1; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (!strcmp(drv1->format_name, format_name)) { - return drv1; - } - } - return NULL; -} - -static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) -{ - static const char *whitelist_rw[] = { - CONFIG_BDRV_RW_WHITELIST - }; - static const char *whitelist_ro[] = { - CONFIG_BDRV_RO_WHITELIST - }; - const char **p; - - if (!whitelist_rw[0] && !whitelist_ro[0]) { - return 1; /* no whitelist, anything goes */ - } - - for (p = whitelist_rw; *p; p++) { - if (!strcmp(drv->format_name, *p)) { - return 1; - } - } - if (read_only) { - for (p = whitelist_ro; *p; p++) { - if (!strcmp(drv->format_name, *p)) { - return 1; - } - } - } - return 0; -} - -bool bdrv_uses_whitelist(void) -{ - return use_bdrv_whitelist; -} - -typedef struct CreateCo { - BlockDriver *drv; - char *filename; - QemuOpts *opts; - int ret; - Error *err; -} CreateCo; - -static void coroutine_fn bdrv_create_co_entry(void *opaque) -{ - Error *local_err = NULL; - int ret; - - CreateCo *cco = opaque; - assert(cco->drv); - - ret = cco->drv->bdrv_create(cco->filename, cco->opts, &local_err); - if (local_err) { - error_propagate(&cco->err, local_err); - } - cco->ret = ret; -} - -int bdrv_create(BlockDriver *drv, const char* filename, - QemuOpts *opts, Error **errp) -{ - int ret; - - Coroutine *co; - CreateCo cco = { - .drv = drv, - .filename = g_strdup(filename), - .opts = opts, - .ret = NOT_DONE, - .err = NULL, - }; - - if (!drv->bdrv_create) { - error_setg(errp, "Driver '%s' does not support image creation", drv->format_name); - ret = -ENOTSUP; - goto out; - } - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_create_co_entry(&cco); - } else { - co = qemu_coroutine_create(bdrv_create_co_entry); - qemu_coroutine_enter(co, &cco); - while (cco.ret == NOT_DONE) { - aio_poll(qemu_get_aio_context(), true); - } - } - - ret = cco.ret; - if (ret < 0) { - if (cco.err) { - error_propagate(errp, cco.err); - } else { - error_setg_errno(errp, -ret, "Could not create image"); - } - } - -out: - g_free(cco.filename); - return ret; -} - -int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp) -{ - BlockDriver *drv; - Error *local_err = NULL; - int ret; - - drv = bdrv_find_protocol(filename, true, errp); - if (drv == NULL) { - return -ENOENT; - } - - ret = bdrv_create(drv, filename, opts, &local_err); - if (local_err) { - error_propagate(errp, local_err); - } - return ret; -} - -/** - * Try to get @bs's logical and physical block size. - * On success, store them in @bsz struct and return 0. - * On failure return -errno. - * @bs must not be empty. - */ -int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_probe_blocksizes) { - return drv->bdrv_probe_blocksizes(bs, bsz); - } - - return -ENOTSUP; -} - -/** - * Try to get @bs's geometry (cyls, heads, sectors). - * On success, store them in @geo struct and return 0. - * On failure return -errno. - * @bs must not be empty. - */ -int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_probe_geometry) { - return drv->bdrv_probe_geometry(bs, geo); - } - - return -ENOTSUP; -} - -/* - * Create a uniquely-named empty temporary file. - * Return 0 upon success, otherwise a negative errno value. - */ -int get_tmp_filename(char *filename, int size) -{ -#ifdef _WIN32 - char temp_dir[MAX_PATH]; - /* GetTempFileName requires that its output buffer (4th param) - have length MAX_PATH or greater. */ - assert(size >= MAX_PATH); - return (GetTempPath(MAX_PATH, temp_dir) - && GetTempFileName(temp_dir, "qem", 0, filename) - ? 0 : -GetLastError()); -#else - int fd; - const char *tmpdir; - tmpdir = getenv("TMPDIR"); - if (!tmpdir) { - tmpdir = "/var/tmp"; - } - if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) { - return -EOVERFLOW; - } - fd = mkstemp(filename); - if (fd < 0) { - return -errno; - } - if (close(fd) != 0) { - unlink(filename); - return -errno; - } - return 0; -#endif -} - -/* - * Detect host devices. By convention, /dev/cdrom[N] is always - * recognized as a host CDROM. - */ -static BlockDriver *find_hdev_driver(const char *filename) -{ - int score_max = 0, score; - BlockDriver *drv = NULL, *d; - - QLIST_FOREACH(d, &bdrv_drivers, list) { - if (d->bdrv_probe_device) { - score = d->bdrv_probe_device(filename); - if (score > score_max) { - score_max = score; - drv = d; - } - } - } - - return drv; -} - -BlockDriver *bdrv_find_protocol(const char *filename, - bool allow_protocol_prefix, - Error **errp) -{ - BlockDriver *drv1; - char protocol[128]; - int len; - const char *p; - - /* TODO Drivers without bdrv_file_open must be specified explicitly */ - - /* - * XXX(hch): we really should not let host device detection - * override an explicit protocol specification, but moving this - * later breaks access to device names with colons in them. - * Thanks to the brain-dead persistent naming schemes on udev- - * based Linux systems those actually are quite common. - */ - drv1 = find_hdev_driver(filename); - if (drv1) { - return drv1; - } - - if (!path_has_protocol(filename) || !allow_protocol_prefix) { - return &bdrv_file; - } - - p = strchr(filename, ':'); - assert(p != NULL); - len = p - filename; - if (len > sizeof(protocol) - 1) - len = sizeof(protocol) - 1; - memcpy(protocol, filename, len); - protocol[len] = '\0'; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (drv1->protocol_name && - !strcmp(drv1->protocol_name, protocol)) { - return drv1; - } - } - - error_setg(errp, "Unknown protocol '%s'", protocol); - return NULL; -} - -/* - * Guess image format by probing its contents. - * This is not a good idea when your image is raw (CVE-2008-2004), but - * we do it anyway for backward compatibility. - * - * @buf contains the image's first @buf_size bytes. - * @buf_size is the buffer size in bytes (generally BLOCK_PROBE_BUF_SIZE, - * but can be smaller if the image file is smaller) - * @filename is its filename. - * - * For all block drivers, call the bdrv_probe() method to get its - * probing score. - * Return the first block driver with the highest probing score. - */ -BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, - const char *filename) -{ - int score_max = 0, score; - BlockDriver *drv = NULL, *d; - - QLIST_FOREACH(d, &bdrv_drivers, list) { - if (d->bdrv_probe) { - score = d->bdrv_probe(buf, buf_size, filename); - if (score > score_max) { - score_max = score; - drv = d; - } - } - } - - return drv; -} - -static int find_image_format(BlockDriverState *bs, const char *filename, - BlockDriver **pdrv, Error **errp) -{ - BlockDriver *drv; - uint8_t buf[BLOCK_PROBE_BUF_SIZE]; - int ret = 0; - - /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ - if (bdrv_is_sg(bs) || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) { - *pdrv = &bdrv_raw; - return ret; - } - - ret = bdrv_pread(bs, 0, buf, sizeof(buf)); - if (ret < 0) { - error_setg_errno(errp, -ret, "Could not read image for determining its " - "format"); - *pdrv = NULL; - return ret; - } - - drv = bdrv_probe_all(buf, ret, filename); - if (!drv) { - error_setg(errp, "Could not determine image format: No compatible " - "driver found"); - ret = -ENOENT; - } - *pdrv = drv; - return ret; -} - -/** - * Set the current 'total_sectors' value - * Return 0 on success, -errno on error. - */ -static int refresh_total_sectors(BlockDriverState *bs, int64_t hint) -{ - BlockDriver *drv = bs->drv; - - /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */ - if (bdrv_is_sg(bs)) - return 0; - - /* query actual device if possible, otherwise just trust the hint */ - if (drv->bdrv_getlength) { - int64_t length = drv->bdrv_getlength(bs); - if (length < 0) { - return length; - } - hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE); - } - - bs->total_sectors = hint; - return 0; -} - -/** - * Combines a QDict of new block driver @options with any missing options taken - * from @old_options, so that leaving out an option defaults to its old value. - */ -static void bdrv_join_options(BlockDriverState *bs, QDict *options, - QDict *old_options) -{ - if (bs->drv && bs->drv->bdrv_join_options) { - bs->drv->bdrv_join_options(options, old_options); - } else { - qdict_join(options, old_options, false); - } -} - -/** - * Set open flags for a given discard mode - * - * Return 0 on success, -1 if the discard mode was invalid. - */ -int bdrv_parse_discard_flags(const char *mode, int *flags) -{ - *flags &= ~BDRV_O_UNMAP; - - if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) { - /* do nothing */ - } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) { - *flags |= BDRV_O_UNMAP; - } else { - return -1; - } - - return 0; -} - -/** - * Set open flags for a given cache mode - * - * Return 0 on success, -1 if the cache mode was invalid. - */ -int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough) -{ - *flags &= ~BDRV_O_CACHE_MASK; - - if (!strcmp(mode, "off") || !strcmp(mode, "none")) { - *writethrough = false; - *flags |= BDRV_O_NOCACHE; - } else if (!strcmp(mode, "directsync")) { - *writethrough = true; - *flags |= BDRV_O_NOCACHE; - } else if (!strcmp(mode, "writeback")) { - *writethrough = false; - } else if (!strcmp(mode, "unsafe")) { - *writethrough = false; - *flags |= BDRV_O_NO_FLUSH; - } else if (!strcmp(mode, "writethrough")) { - *writethrough = true; - } else { - return -1; - } - - return 0; -} - -/* - * Returns the options and flags that a temporary snapshot should get, based on - * the originally requested flags (the originally requested image will have - * flags like a backing file) - */ -static void bdrv_temp_snapshot_options(int *child_flags, QDict *child_options, - int parent_flags, QDict *parent_options) -{ - *child_flags = (parent_flags & ~BDRV_O_SNAPSHOT) | BDRV_O_TEMPORARY; - - /* For temporary files, unconditional cache=unsafe is fine */ - qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off"); - qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); -} - -/* - * Returns the options and flags that bs->file should get if a protocol driver - * is expected, based on the given options and flags for the parent BDS - */ -static void bdrv_inherited_options(int *child_flags, QDict *child_options, - int parent_flags, QDict *parent_options) -{ - int flags = parent_flags; - - /* Enable protocol handling, disable format probing for bs->file */ - flags |= BDRV_O_PROTOCOL; - - /* If the cache mode isn't explicitly set, inherit direct and no-flush from - * the parent. */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT); - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH); - - /* Our block drivers take care to send flushes and respect unmap policy, - * so we can default to enable both on lower layers regardless of the - * corresponding parent options. */ - flags |= BDRV_O_UNMAP; - - /* Clear flags that only apply to the top layer */ - flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ | - BDRV_O_NO_IO); - - *child_flags = flags; -} - -const BdrvChildRole child_file = { - .inherit_options = bdrv_inherited_options, -}; - -/* - * Returns the options and flags that bs->file should get if the use of formats - * (and not only protocols) is permitted for it, based on the given options and - * flags for the parent BDS - */ -static void bdrv_inherited_fmt_options(int *child_flags, QDict *child_options, - int parent_flags, QDict *parent_options) -{ - child_file.inherit_options(child_flags, child_options, - parent_flags, parent_options); - - *child_flags &= ~(BDRV_O_PROTOCOL | BDRV_O_NO_IO); -} - -const BdrvChildRole child_format = { - .inherit_options = bdrv_inherited_fmt_options, -}; - -/* - * Returns the options and flags that bs->backing should get, based on the - * given options and flags for the parent BDS - */ -static void bdrv_backing_options(int *child_flags, QDict *child_options, - int parent_flags, QDict *parent_options) -{ - int flags = parent_flags; - - /* The cache mode is inherited unmodified for backing files; except WCE, - * which is only applied on the top level (BlockBackend) */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT); - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH); - - /* backing files always opened read-only */ - flags &= ~(BDRV_O_RDWR | BDRV_O_COPY_ON_READ); - - /* snapshot=on is handled on the top layer */ - flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_TEMPORARY); - - *child_flags = flags; -} - -static const BdrvChildRole child_backing = { - .inherit_options = bdrv_backing_options, -}; - -static int bdrv_open_flags(BlockDriverState *bs, int flags) -{ - int open_flags = flags; - - /* - * Clear flags that are internal to the block layer before opening the - * image. - */ - open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL); - - /* - * Snapshots should be writable. - */ - if (flags & BDRV_O_TEMPORARY) { - open_flags |= BDRV_O_RDWR; - } - - return open_flags; -} - -static void update_flags_from_options(int *flags, QemuOpts *opts) -{ - *flags &= ~BDRV_O_CACHE_MASK; - - assert(qemu_opt_find(opts, BDRV_OPT_CACHE_NO_FLUSH)); - if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) { - *flags |= BDRV_O_NO_FLUSH; - } - - assert(qemu_opt_find(opts, BDRV_OPT_CACHE_DIRECT)); - if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_DIRECT, false)) { - *flags |= BDRV_O_NOCACHE; - } -} - -static void update_options_from_flags(QDict *options, int flags) -{ - if (!qdict_haskey(options, BDRV_OPT_CACHE_DIRECT)) { - qdict_put(options, BDRV_OPT_CACHE_DIRECT, - qbool_from_bool(flags & BDRV_O_NOCACHE)); - } - if (!qdict_haskey(options, BDRV_OPT_CACHE_NO_FLUSH)) { - qdict_put(options, BDRV_OPT_CACHE_NO_FLUSH, - qbool_from_bool(flags & BDRV_O_NO_FLUSH)); - } -} - -static void bdrv_assign_node_name(BlockDriverState *bs, - const char *node_name, - Error **errp) -{ - char *gen_node_name = NULL; - - if (!node_name) { - node_name = gen_node_name = id_generate(ID_BLOCK); - } else if (!id_wellformed(node_name)) { - /* - * Check for empty string or invalid characters, but not if it is - * generated (generated names use characters not available to the user) - */ - error_setg(errp, "Invalid node name"); - return; - } - - /* takes care of avoiding namespaces collisions */ - if (blk_by_name(node_name)) { - error_setg(errp, "node-name=%s is conflicting with a device id", - node_name); - goto out; - } - - /* takes care of avoiding duplicates node names */ - if (bdrv_find_node(node_name)) { - error_setg(errp, "Duplicate node name"); - goto out; - } - - /* copy node name into the bs and insert it into the graph list */ - pstrcpy(bs->node_name, sizeof(bs->node_name), node_name); - QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list); -out: - g_free(gen_node_name); -} - -static QemuOptsList bdrv_runtime_opts = { - .name = "bdrv_common", - .head = QTAILQ_HEAD_INITIALIZER(bdrv_runtime_opts.head), - .desc = { - { - .name = "node-name", - .type = QEMU_OPT_STRING, - .help = "Node name of the block device node", - }, - { - .name = "driver", - .type = QEMU_OPT_STRING, - .help = "Block driver to use for the node", - }, - { - .name = BDRV_OPT_CACHE_DIRECT, - .type = QEMU_OPT_BOOL, - .help = "Bypass software writeback cache on the host", - }, - { - .name = BDRV_OPT_CACHE_NO_FLUSH, - .type = QEMU_OPT_BOOL, - .help = "Ignore flush requests", - }, - { /* end of list */ } - }, -}; - -/* - * Common part for opening disk images and files - * - * Removes all processed options from *options. - */ -static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file, - QDict *options, Error **errp) -{ - int ret, open_flags; - const char *filename; - const char *driver_name = NULL; - const char *node_name = NULL; - QemuOpts *opts; - BlockDriver *drv; - Error *local_err = NULL; - - assert(bs->file == NULL); - assert(options != NULL && bs->options != options); - - opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); - qemu_opts_absorb_qdict(opts, options, &local_err); - if (local_err) { - error_propagate(errp, local_err); - ret = -EINVAL; - goto fail_opts; - } - - driver_name = qemu_opt_get(opts, "driver"); - drv = bdrv_find_format(driver_name); - assert(drv != NULL); - - if (file != NULL) { - filename = file->bs->filename; - } else { - filename = qdict_get_try_str(options, "filename"); - } - - if (drv->bdrv_needs_filename && !filename) { - error_setg(errp, "The '%s' block driver requires a file name", - drv->format_name); - ret = -EINVAL; - goto fail_opts; - } - - trace_bdrv_open_common(bs, filename ?: "", bs->open_flags, - drv->format_name); - - node_name = qemu_opt_get(opts, "node-name"); - bdrv_assign_node_name(bs, node_name, &local_err); - if (local_err) { - error_propagate(errp, local_err); - ret = -EINVAL; - goto fail_opts; - } - - bs->request_alignment = 512; - bs->zero_beyond_eof = true; - bs->read_only = !(bs->open_flags & BDRV_O_RDWR); - - if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) { - error_setg(errp, - !bs->read_only && bdrv_is_whitelisted(drv, true) - ? "Driver '%s' can only be used for read-only devices" - : "Driver '%s' is not whitelisted", - drv->format_name); - ret = -ENOTSUP; - goto fail_opts; - } - - assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */ - if (bs->open_flags & BDRV_O_COPY_ON_READ) { - if (!bs->read_only) { - bdrv_enable_copy_on_read(bs); - } else { - error_setg(errp, "Can't use copy-on-read on read-only device"); - ret = -EINVAL; - goto fail_opts; - } - } - - if (filename != NULL) { - pstrcpy(bs->filename, sizeof(bs->filename), filename); - } else { - bs->filename[0] = '\0'; - } - pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), bs->filename); - - bs->drv = drv; - bs->opaque = g_malloc0(drv->instance_size); - - /* Apply cache mode options */ - update_flags_from_options(&bs->open_flags, opts); - - /* Open the image, either directly or using a protocol */ - open_flags = bdrv_open_flags(bs, bs->open_flags); - if (drv->bdrv_file_open) { - assert(file == NULL); - assert(!drv->bdrv_needs_filename || filename != NULL); - ret = drv->bdrv_file_open(bs, options, open_flags, &local_err); - } else { - if (file == NULL) { - error_setg(errp, "Can't use '%s' as a block driver for the " - "protocol level", drv->format_name); - ret = -EINVAL; - goto free_and_fail; - } - bs->file = file; - ret = drv->bdrv_open(bs, options, open_flags, &local_err); - } - - if (ret < 0) { - if (local_err) { - error_propagate(errp, local_err); - } else if (bs->filename[0]) { - error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename); - } else { - error_setg_errno(errp, -ret, "Could not open image"); - } - goto free_and_fail; - } - - ret = refresh_total_sectors(bs, bs->total_sectors); - if (ret < 0) { - error_setg_errno(errp, -ret, "Could not refresh total sector count"); - goto free_and_fail; - } - - bdrv_refresh_limits(bs, &local_err); - if (local_err) { - error_propagate(errp, local_err); - ret = -EINVAL; - goto free_and_fail; - } - - assert(bdrv_opt_mem_align(bs) != 0); - assert(bdrv_min_mem_align(bs) != 0); - assert((bs->request_alignment != 0) || bdrv_is_sg(bs)); - - qemu_opts_del(opts); - return 0; - -free_and_fail: - bs->file = NULL; - g_free(bs->opaque); - bs->opaque = NULL; - bs->drv = NULL; -fail_opts: - qemu_opts_del(opts); - return ret; -} - -static QDict *parse_json_filename(const char *filename, Error **errp) -{ - QObject *options_obj; - QDict *options; - int ret; - - ret = strstart(filename, "json:", &filename); - assert(ret); - - options_obj = qobject_from_json(filename); - if (!options_obj) { - error_setg(errp, "Could not parse the JSON options"); - return NULL; - } - - if (qobject_type(options_obj) != QTYPE_QDICT) { - qobject_decref(options_obj); - error_setg(errp, "Invalid JSON object given"); - return NULL; - } - - options = qobject_to_qdict(options_obj); - qdict_flatten(options); - - return options; -} - -static void parse_json_protocol(QDict *options, const char **pfilename, - Error **errp) -{ - QDict *json_options; - Error *local_err = NULL; - - /* Parse json: pseudo-protocol */ - if (!*pfilename || !g_str_has_prefix(*pfilename, "json:")) { - return; - } - - json_options = parse_json_filename(*pfilename, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return; - } - - /* Options given in the filename have lower priority than options - * specified directly */ - qdict_join(options, json_options, false); - QDECREF(json_options); - *pfilename = NULL; -} - -/* - * Fills in default options for opening images and converts the legacy - * filename/flags pair to option QDict entries. - * The BDRV_O_PROTOCOL flag in *flags will be set or cleared accordingly if a - * block driver has been specified explicitly. - */ -static int bdrv_fill_options(QDict **options, const char *filename, - int *flags, Error **errp) -{ - const char *drvname; - bool protocol = *flags & BDRV_O_PROTOCOL; - bool parse_filename = false; - BlockDriver *drv = NULL; - Error *local_err = NULL; - - drvname = qdict_get_try_str(*options, "driver"); - if (drvname) { - drv = bdrv_find_format(drvname); - if (!drv) { - error_setg(errp, "Unknown driver '%s'", drvname); - return -ENOENT; - } - /* If the user has explicitly specified the driver, this choice should - * override the BDRV_O_PROTOCOL flag */ - protocol = drv->bdrv_file_open; - } - - if (protocol) { - *flags |= BDRV_O_PROTOCOL; - } else { - *flags &= ~BDRV_O_PROTOCOL; - } - - /* Translate cache options from flags into options */ - update_options_from_flags(*options, *flags); - - /* Fetch the file name from the options QDict if necessary */ - if (protocol && filename) { - if (!qdict_haskey(*options, "filename")) { - qdict_put(*options, "filename", qstring_from_str(filename)); - parse_filename = true; - } else { - error_setg(errp, "Can't specify 'file' and 'filename' options at " - "the same time"); - return -EINVAL; - } - } - - /* Find the right block driver */ - filename = qdict_get_try_str(*options, "filename"); - - if (!drvname && protocol) { - if (filename) { - drv = bdrv_find_protocol(filename, parse_filename, errp); - if (!drv) { - return -EINVAL; - } - - drvname = drv->format_name; - qdict_put(*options, "driver", qstring_from_str(drvname)); - } else { - error_setg(errp, "Must specify either driver or file"); - return -EINVAL; - } - } - - assert(drv || !protocol); - - /* Driver-specific filename parsing */ - if (drv && drv->bdrv_parse_filename && parse_filename) { - drv->bdrv_parse_filename(filename, *options, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return -EINVAL; - } - - if (!drv->bdrv_needs_filename) { - qdict_del(*options, "filename"); - } - } - - return 0; -} - -BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, - const char *child_name, - const BdrvChildRole *child_role) -{ - BdrvChild *child = g_new(BdrvChild, 1); - *child = (BdrvChild) { - .bs = child_bs, - .name = g_strdup(child_name), - .role = child_role, - }; - - QLIST_INSERT_HEAD(&child_bs->parents, child, next_parent); - - return child; -} - -static BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, - BlockDriverState *child_bs, - const char *child_name, - const BdrvChildRole *child_role) -{ - BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role); - QLIST_INSERT_HEAD(&parent_bs->children, child, next); - return child; -} - -static void bdrv_detach_child(BdrvChild *child) -{ - if (child->next.le_prev) { - QLIST_REMOVE(child, next); - child->next.le_prev = NULL; - } - QLIST_REMOVE(child, next_parent); - g_free(child->name); - g_free(child); -} - -void bdrv_root_unref_child(BdrvChild *child) -{ - BlockDriverState *child_bs; - - child_bs = child->bs; - bdrv_detach_child(child); - bdrv_unref(child_bs); -} - -void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child) -{ - if (child == NULL) { - return; - } - - if (child->bs->inherits_from == parent) { - child->bs->inherits_from = NULL; - } - - bdrv_root_unref_child(child); -} - -/* - * Sets the backing file link of a BDS. A new reference is created; callers - * which don't need their own reference any more must call bdrv_unref(). - */ -void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) -{ - if (backing_hd) { - bdrv_ref(backing_hd); - } - - if (bs->backing) { - assert(bs->backing_blocker); - bdrv_op_unblock_all(bs->backing->bs, bs->backing_blocker); - bdrv_unref_child(bs, bs->backing); - } else if (backing_hd) { - error_setg(&bs->backing_blocker, - "node is used as backing hd of '%s'", - bdrv_get_device_or_node_name(bs)); - } - - if (!backing_hd) { - error_free(bs->backing_blocker); - bs->backing_blocker = NULL; - bs->backing = NULL; - goto out; - } - bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing); - bs->open_flags &= ~BDRV_O_NO_BACKING; - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), - backing_hd->drv ? backing_hd->drv->format_name : ""); - - bdrv_op_block_all(backing_hd, bs->backing_blocker); - /* Otherwise we won't be able to commit due to check in bdrv_commit */ - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, - bs->backing_blocker); -out: - bdrv_refresh_limits(bs, NULL); -} - -/* - * Opens the backing file for a BlockDriverState if not yet open - * - * bdref_key specifies the key for the image's BlockdevRef in the options QDict. - * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict - * itself, all options starting with "${bdref_key}." are considered part of the - * BlockdevRef. - * - * TODO Can this be unified with bdrv_open_image()? - */ -int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, - const char *bdref_key, Error **errp) -{ - char *backing_filename = g_malloc0(PATH_MAX); - char *bdref_key_dot; - const char *reference = NULL; - int ret = 0; - BlockDriverState *backing_hd; - QDict *options; - QDict *tmp_parent_options = NULL; - Error *local_err = NULL; - - if (bs->backing != NULL) { - goto free_exit; - } - - /* NULL means an empty set of options */ - if (parent_options == NULL) { - tmp_parent_options = qdict_new(); - parent_options = tmp_parent_options; - } - - bs->open_flags &= ~BDRV_O_NO_BACKING; - - bdref_key_dot = g_strdup_printf("%s.", bdref_key); - qdict_extract_subqdict(parent_options, &options, bdref_key_dot); - g_free(bdref_key_dot); - - reference = qdict_get_try_str(parent_options, bdref_key); - if (reference || qdict_haskey(options, "file.filename")) { - backing_filename[0] = '\0'; - } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { - QDECREF(options); - goto free_exit; - } else { - bdrv_get_full_backing_filename(bs, backing_filename, PATH_MAX, - &local_err); - if (local_err) { - ret = -EINVAL; - error_propagate(errp, local_err); - QDECREF(options); - goto free_exit; - } - } - - if (!bs->drv || !bs->drv->supports_backing) { - ret = -EINVAL; - error_setg(errp, "Driver doesn't support backing files"); - QDECREF(options); - goto free_exit; - } - - if (bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) { - qdict_put(options, "driver", qstring_from_str(bs->backing_format)); - } - - backing_hd = NULL; - ret = bdrv_open_inherit(&backing_hd, - *backing_filename ? backing_filename : NULL, - reference, options, 0, bs, &child_backing, - errp); - if (ret < 0) { - bs->open_flags |= BDRV_O_NO_BACKING; - error_prepend(errp, "Could not open backing file: "); - goto free_exit; - } - - /* Hook up the backing file link; drop our reference, bs owns the - * backing_hd reference now */ - bdrv_set_backing_hd(bs, backing_hd); - bdrv_unref(backing_hd); - - qdict_del(parent_options, bdref_key); - -free_exit: - g_free(backing_filename); - QDECREF(tmp_parent_options); - return ret; -} - -/* - * Opens a disk image whose options are given as BlockdevRef in another block - * device's options. - * - * If allow_none is true, no image will be opened if filename is false and no - * BlockdevRef is given. NULL will be returned, but errp remains unset. - * - * bdrev_key specifies the key for the image's BlockdevRef in the options QDict. - * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict - * itself, all options starting with "${bdref_key}." are considered part of the - * BlockdevRef. - * - * The BlockdevRef will be removed from the options QDict. - */ -BdrvChild *bdrv_open_child(const char *filename, - QDict *options, const char *bdref_key, - BlockDriverState* parent, - const BdrvChildRole *child_role, - bool allow_none, Error **errp) -{ - BdrvChild *c = NULL; - BlockDriverState *bs; - QDict *image_options; - int ret; - char *bdref_key_dot; - const char *reference; - - assert(child_role != NULL); - - bdref_key_dot = g_strdup_printf("%s.", bdref_key); - qdict_extract_subqdict(options, &image_options, bdref_key_dot); - g_free(bdref_key_dot); - - reference = qdict_get_try_str(options, bdref_key); - if (!filename && !reference && !qdict_size(image_options)) { - if (!allow_none) { - error_setg(errp, "A block device must be specified for \"%s\"", - bdref_key); - } - QDECREF(image_options); - goto done; - } - - bs = NULL; - ret = bdrv_open_inherit(&bs, filename, reference, image_options, 0, - parent, child_role, errp); - if (ret < 0) { - goto done; - } - - c = bdrv_attach_child(parent, bs, bdref_key, child_role); - -done: - qdict_del(options, bdref_key); - return c; -} - -static int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, - QDict *snapshot_options, Error **errp) -{ - /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ - char *tmp_filename = g_malloc0(PATH_MAX + 1); - int64_t total_size; - QemuOpts *opts = NULL; - BlockDriverState *bs_snapshot; - Error *local_err = NULL; - int ret; - - /* if snapshot, we create a temporary backing file and open it - instead of opening 'filename' directly */ - - /* Get the required size from the image */ - total_size = bdrv_getlength(bs); - if (total_size < 0) { - ret = total_size; - error_setg_errno(errp, -total_size, "Could not get image size"); - goto out; - } - - /* Create the temporary image */ - ret = get_tmp_filename(tmp_filename, PATH_MAX + 1); - if (ret < 0) { - error_setg_errno(errp, -ret, "Could not get temporary filename"); - goto out; - } - - opts = qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0, - &error_abort); - qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort); - ret = bdrv_create(&bdrv_qcow2, tmp_filename, opts, errp); - qemu_opts_del(opts); - if (ret < 0) { - error_prepend(errp, "Could not create temporary overlay '%s': ", - tmp_filename); - goto out; - } - - /* Prepare options QDict for the temporary file */ - qdict_put(snapshot_options, "file.driver", - qstring_from_str("file")); - qdict_put(snapshot_options, "file.filename", - qstring_from_str(tmp_filename)); - qdict_put(snapshot_options, "driver", - qstring_from_str("qcow2")); - - bs_snapshot = bdrv_new(); - - ret = bdrv_open(&bs_snapshot, NULL, NULL, snapshot_options, - flags, &local_err); - snapshot_options = NULL; - if (ret < 0) { - error_propagate(errp, local_err); - goto out; - } - - bdrv_append(bs_snapshot, bs); - -out: - QDECREF(snapshot_options); - g_free(tmp_filename); - return ret; -} - -/* - * Opens a disk image (raw, qcow2, vmdk, ...) - * - * options is a QDict of options to pass to the block drivers, or NULL for an - * empty set of options. The reference to the QDict belongs to the block layer - * after the call (even on failure), so if the caller intends to reuse the - * dictionary, it needs to use QINCREF() before calling bdrv_open. - * - * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. - * If it is not NULL, the referenced BDS will be reused. - * - * The reference parameter may be used to specify an existing block device which - * should be opened. If specified, neither options nor a filename may be given, - * nor can an existing BDS be reused (that is, *pbs has to be NULL). - */ -static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename, - const char *reference, QDict *options, int flags, - BlockDriverState *parent, - const BdrvChildRole *child_role, Error **errp) -{ - int ret; - BdrvChild *file = NULL; - BlockDriverState *bs; - BlockDriver *drv = NULL; - const char *drvname; - const char *backing; - Error *local_err = NULL; - QDict *snapshot_options = NULL; - int snapshot_flags = 0; - - assert(pbs); - assert(!child_role || !flags); - assert(!child_role == !parent); - - if (reference) { - bool options_non_empty = options ? qdict_size(options) : false; - QDECREF(options); - - if (*pbs) { - error_setg(errp, "Cannot reuse an existing BDS when referencing " - "another block device"); - return -EINVAL; - } - - if (filename || options_non_empty) { - error_setg(errp, "Cannot reference an existing block device with " - "additional options or a new filename"); - return -EINVAL; - } - - bs = bdrv_lookup_bs(reference, reference, errp); - if (!bs) { - return -ENODEV; - } - - if (bs->throttle_state) { - error_setg(errp, "Cannot reference an existing block device for " - "which I/O throttling is enabled"); - return -EINVAL; - } - - bdrv_ref(bs); - *pbs = bs; - return 0; - } - - if (*pbs) { - bs = *pbs; - } else { - bs = bdrv_new(); - } - - /* NULL means an empty set of options */ - if (options == NULL) { - options = qdict_new(); - } - - /* json: syntax counts as explicit options, as if in the QDict */ - parse_json_protocol(options, &filename, &local_err); - if (local_err) { - ret = -EINVAL; - goto fail; - } - - bs->explicit_options = qdict_clone_shallow(options); - - if (child_role) { - bs->inherits_from = parent; - child_role->inherit_options(&flags, options, - parent->open_flags, parent->options); - } - - ret = bdrv_fill_options(&options, filename, &flags, &local_err); - if (local_err) { - goto fail; - } - - bs->open_flags = flags; - bs->options = options; - options = qdict_clone_shallow(options); - - /* Find the right image format driver */ - drvname = qdict_get_try_str(options, "driver"); - if (drvname) { - drv = bdrv_find_format(drvname); - if (!drv) { - error_setg(errp, "Unknown driver: '%s'", drvname); - ret = -EINVAL; - goto fail; - } - } - - assert(drvname || !(flags & BDRV_O_PROTOCOL)); - - backing = qdict_get_try_str(options, "backing"); - if (backing && *backing == '\0') { - flags |= BDRV_O_NO_BACKING; - qdict_del(options, "backing"); - } - - /* Open image file without format layer */ - if ((flags & BDRV_O_PROTOCOL) == 0) { - if (flags & BDRV_O_RDWR) { - flags |= BDRV_O_ALLOW_RDWR; - } - if (flags & BDRV_O_SNAPSHOT) { - snapshot_options = qdict_new(); - bdrv_temp_snapshot_options(&snapshot_flags, snapshot_options, - flags, options); - bdrv_backing_options(&flags, options, flags, options); - } - - bs->open_flags = flags; - - file = bdrv_open_child(filename, options, "file", bs, - &child_file, true, &local_err); - if (local_err) { - ret = -EINVAL; - goto fail; - } - } - - /* Image format probing */ - bs->probed = !drv; - if (!drv && file) { - ret = find_image_format(file->bs, filename, &drv, &local_err); - if (ret < 0) { - goto fail; - } - /* - * This option update would logically belong in bdrv_fill_options(), - * but we first need to open bs->file for the probing to work, while - * opening bs->file already requires the (mostly) final set of options - * so that cache mode etc. can be inherited. - * - * Adding the driver later is somewhat ugly, but it's not an option - * that would ever be inherited, so it's correct. We just need to make - * sure to update both bs->options (which has the full effective - * options for bs) and options (which has file.* already removed). - */ - qdict_put(bs->options, "driver", qstring_from_str(drv->format_name)); - qdict_put(options, "driver", qstring_from_str(drv->format_name)); - } else if (!drv) { - error_setg(errp, "Must specify either driver or file"); - ret = -EINVAL; - goto fail; - } - - /* BDRV_O_PROTOCOL must be set iff a protocol BDS is about to be created */ - assert(!!(flags & BDRV_O_PROTOCOL) == !!drv->bdrv_file_open); - /* file must be NULL if a protocol BDS is about to be created - * (the inverse results in an error message from bdrv_open_common()) */ - assert(!(flags & BDRV_O_PROTOCOL) || !file); - - /* Open the image */ - ret = bdrv_open_common(bs, file, options, &local_err); - if (ret < 0) { - goto fail; - } - - if (file && (bs->file != file)) { - bdrv_unref_child(bs, file); - file = NULL; - } - - /* If there is a backing file, use it */ - if ((flags & BDRV_O_NO_BACKING) == 0) { - ret = bdrv_open_backing_file(bs, options, "backing", &local_err); - if (ret < 0) { - goto close_and_fail; - } - } - - bdrv_refresh_filename(bs); - - /* Check if any unknown options were used */ - if (options && (qdict_size(options) != 0)) { - const QDictEntry *entry = qdict_first(options); - if (flags & BDRV_O_PROTOCOL) { - error_setg(errp, "Block protocol '%s' doesn't support the option " - "'%s'", drv->format_name, entry->key); - } else { - error_setg(errp, - "Block format '%s' does not support the option '%s'", - drv->format_name, entry->key); - } - - ret = -EINVAL; - goto close_and_fail; - } - - if (!bdrv_key_required(bs)) { - if (bs->blk) { - blk_dev_change_media_cb(bs->blk, true); - } - } else if (!runstate_check(RUN_STATE_PRELAUNCH) - && !runstate_check(RUN_STATE_INMIGRATE) - && !runstate_check(RUN_STATE_PAUSED)) { /* HACK */ - error_setg(errp, - "Guest must be stopped for opening of encrypted image"); - ret = -EBUSY; - goto close_and_fail; - } - - QDECREF(options); - *pbs = bs; - - /* For snapshot=on, create a temporary qcow2 overlay. bs points to the - * temporary snapshot afterwards. */ - if (snapshot_flags) { - ret = bdrv_append_temp_snapshot(bs, snapshot_flags, snapshot_options, - &local_err); - snapshot_options = NULL; - if (local_err) { - goto close_and_fail; - } - } - - return 0; - -fail: - if (file != NULL) { - bdrv_unref_child(bs, file); - } - QDECREF(snapshot_options); - QDECREF(bs->explicit_options); - QDECREF(bs->options); - QDECREF(options); - bs->options = NULL; - if (!*pbs) { - /* If *pbs is NULL, a new BDS has been created in this function and - needs to be freed now. Otherwise, it does not need to be closed, - since it has not really been opened yet. */ - bdrv_unref(bs); - } - if (local_err) { - error_propagate(errp, local_err); - } - return ret; - -close_and_fail: - /* See fail path, but now the BDS has to be always closed */ - if (*pbs) { - bdrv_close(bs); - } else { - bdrv_unref(bs); - } - QDECREF(snapshot_options); - QDECREF(options); - if (local_err) { - error_propagate(errp, local_err); - } - return ret; -} - -int bdrv_open(BlockDriverState **pbs, const char *filename, - const char *reference, QDict *options, int flags, Error **errp) -{ - return bdrv_open_inherit(pbs, filename, reference, options, flags, NULL, - NULL, errp); -} - -typedef struct BlockReopenQueueEntry { - bool prepared; - BDRVReopenState state; - QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry; -} BlockReopenQueueEntry; - -/* - * Adds a BlockDriverState to a simple queue for an atomic, transactional - * reopen of multiple devices. - * - * bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT - * already performed, or alternatively may be NULL a new BlockReopenQueue will - * be created and initialized. This newly created BlockReopenQueue should be - * passed back in for subsequent calls that are intended to be of the same - * atomic 'set'. - * - * bs is the BlockDriverState to add to the reopen queue. - * - * options contains the changed options for the associated bs - * (the BlockReopenQueue takes ownership) - * - * flags contains the open flags for the associated bs - * - * returns a pointer to bs_queue, which is either the newly allocated - * bs_queue, or the existing bs_queue being used. - * - */ -static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, - BlockDriverState *bs, - QDict *options, - int flags, - const BdrvChildRole *role, - QDict *parent_options, - int parent_flags) -{ - assert(bs != NULL); - - BlockReopenQueueEntry *bs_entry; - BdrvChild *child; - QDict *old_options, *explicit_options; - - if (bs_queue == NULL) { - bs_queue = g_new0(BlockReopenQueue, 1); - QSIMPLEQ_INIT(bs_queue); - } - - if (!options) { - options = qdict_new(); - } - - /* - * Precedence of options: - * 1. Explicitly passed in options (highest) - * 2. Set in flags (only for top level) - * 3. Retained from explicitly set options of bs - * 4. Inherited from parent node - * 5. Retained from effective options of bs - */ - - if (!parent_options) { - /* - * Any setting represented by flags is always updated. If the - * corresponding QDict option is set, it takes precedence. Otherwise - * the flag is translated into a QDict option. The old setting of bs is - * not considered. - */ - update_options_from_flags(options, flags); - } - - /* Old explicitly set values (don't overwrite by inherited value) */ - old_options = qdict_clone_shallow(bs->explicit_options); - bdrv_join_options(bs, options, old_options); - QDECREF(old_options); - - explicit_options = qdict_clone_shallow(options); - - /* Inherit from parent node */ - if (parent_options) { - assert(!flags); - role->inherit_options(&flags, options, parent_flags, parent_options); - } - - /* Old values are used for options that aren't set yet */ - old_options = qdict_clone_shallow(bs->options); - bdrv_join_options(bs, options, old_options); - QDECREF(old_options); - - /* bdrv_open() masks this flag out */ - flags &= ~BDRV_O_PROTOCOL; - - QLIST_FOREACH(child, &bs->children, next) { - QDict *new_child_options; - char *child_key_dot; - - /* reopen can only change the options of block devices that were - * implicitly created and inherited options. For other (referenced) - * block devices, a syntax like "backing.foo" results in an error. */ - if (child->bs->inherits_from != bs) { - continue; - } - - child_key_dot = g_strdup_printf("%s.", child->name); - qdict_extract_subqdict(options, &new_child_options, child_key_dot); - g_free(child_key_dot); - - bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options, 0, - child->role, options, flags); - } - - bs_entry = g_new0(BlockReopenQueueEntry, 1); - QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry); - - bs_entry->state.bs = bs; - bs_entry->state.options = options; - bs_entry->state.explicit_options = explicit_options; - bs_entry->state.flags = flags; - - return bs_queue; -} - -BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, - BlockDriverState *bs, - QDict *options, int flags) -{ - return bdrv_reopen_queue_child(bs_queue, bs, options, flags, - NULL, NULL, 0); -} - -/* - * Reopen multiple BlockDriverStates atomically & transactionally. - * - * The queue passed in (bs_queue) must have been built up previous - * via bdrv_reopen_queue(). - * - * Reopens all BDS specified in the queue, with the appropriate - * flags. All devices are prepared for reopen, and failure of any - * device will cause all device changes to be abandonded, and intermediate - * data cleaned up. - * - * If all devices prepare successfully, then the changes are committed - * to all devices. - * - */ -int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) -{ - int ret = -1; - BlockReopenQueueEntry *bs_entry, *next; - Error *local_err = NULL; - - assert(bs_queue != NULL); - - bdrv_drain_all(); - - QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) { - if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) { - error_propagate(errp, local_err); - goto cleanup; - } - bs_entry->prepared = true; - } - - /* If we reach this point, we have success and just need to apply the - * changes - */ - QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) { - bdrv_reopen_commit(&bs_entry->state); - } - - ret = 0; - -cleanup: - QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { - if (ret && bs_entry->prepared) { - bdrv_reopen_abort(&bs_entry->state); - } else if (ret) { - QDECREF(bs_entry->state.explicit_options); - } - QDECREF(bs_entry->state.options); - g_free(bs_entry); - } - g_free(bs_queue); - return ret; -} - - -/* Reopen a single BlockDriverState with the specified flags. */ -int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp) -{ - int ret = -1; - Error *local_err = NULL; - BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, NULL, bdrv_flags); - - ret = bdrv_reopen_multiple(queue, &local_err); - if (local_err != NULL) { - error_propagate(errp, local_err); - } - return ret; -} - - -/* - * Prepares a BlockDriverState for reopen. All changes are staged in the - * 'opaque' field of the BDRVReopenState, which is used and allocated by - * the block driver layer .bdrv_reopen_prepare() - * - * bs is the BlockDriverState to reopen - * flags are the new open flags - * queue is the reopen queue - * - * Returns 0 on success, non-zero on error. On error errp will be set - * as well. - * - * On failure, bdrv_reopen_abort() will be called to clean up any data. - * It is the responsibility of the caller to then call the abort() or - * commit() for any other BDS that have been left in a prepare() state - * - */ -int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, - Error **errp) -{ - int ret = -1; - Error *local_err = NULL; - BlockDriver *drv; - QemuOpts *opts; - const char *value; - - assert(reopen_state != NULL); - assert(reopen_state->bs->drv != NULL); - drv = reopen_state->bs->drv; - - /* Process generic block layer options */ - opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); - qemu_opts_absorb_qdict(opts, reopen_state->options, &local_err); - if (local_err) { - error_propagate(errp, local_err); - ret = -EINVAL; - goto error; - } - - update_flags_from_options(&reopen_state->flags, opts); - - /* node-name and driver must be unchanged. Put them back into the QDict, so - * that they are checked at the end of this function. */ - value = qemu_opt_get(opts, "node-name"); - if (value) { - qdict_put(reopen_state->options, "node-name", qstring_from_str(value)); - } - - value = qemu_opt_get(opts, "driver"); - if (value) { - qdict_put(reopen_state->options, "driver", qstring_from_str(value)); - } - - /* if we are to stay read-only, do not allow permission change - * to r/w */ - if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) && - reopen_state->flags & BDRV_O_RDWR) { - error_setg(errp, "Node '%s' is read only", - bdrv_get_device_or_node_name(reopen_state->bs)); - goto error; - } - - - ret = bdrv_flush(reopen_state->bs); - if (ret) { - error_setg_errno(errp, -ret, "Error flushing drive"); - goto error; - } - - if (drv->bdrv_reopen_prepare) { - ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err); - if (ret) { - if (local_err != NULL) { - error_propagate(errp, local_err); - } else { - error_setg(errp, "failed while preparing to reopen image '%s'", - reopen_state->bs->filename); - } - goto error; - } - } else { - /* It is currently mandatory to have a bdrv_reopen_prepare() - * handler for each supported drv. */ - error_setg(errp, "Block format '%s' used by node '%s' " - "does not support reopening files", drv->format_name, - bdrv_get_device_or_node_name(reopen_state->bs)); - ret = -1; - goto error; - } - - /* Options that are not handled are only okay if they are unchanged - * compared to the old state. It is expected that some options are only - * used for the initial open, but not reopen (e.g. filename) */ - if (qdict_size(reopen_state->options)) { - const QDictEntry *entry = qdict_first(reopen_state->options); - - do { - QString *new_obj = qobject_to_qstring(entry->value); - const char *new = qstring_get_str(new_obj); - const char *old = qdict_get_try_str(reopen_state->bs->options, - entry->key); - - if (!old || strcmp(new, old)) { - error_setg(errp, "Cannot change the option '%s'", entry->key); - ret = -EINVAL; - goto error; - } - } while ((entry = qdict_next(reopen_state->options, entry))); - } - - ret = 0; - -error: - qemu_opts_del(opts); - return ret; -} - -/* - * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and - * makes them final by swapping the staging BlockDriverState contents into - * the active BlockDriverState contents. - */ -void bdrv_reopen_commit(BDRVReopenState *reopen_state) -{ - BlockDriver *drv; - - assert(reopen_state != NULL); - drv = reopen_state->bs->drv; - assert(drv != NULL); - - /* If there are any driver level actions to take */ - if (drv->bdrv_reopen_commit) { - drv->bdrv_reopen_commit(reopen_state); - } - - /* set BDS specific flags now */ - QDECREF(reopen_state->bs->explicit_options); - - reopen_state->bs->explicit_options = reopen_state->explicit_options; - reopen_state->bs->open_flags = reopen_state->flags; - reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR); - - bdrv_refresh_limits(reopen_state->bs, NULL); -} - -/* - * Abort the reopen, and delete and free the staged changes in - * reopen_state - */ -void bdrv_reopen_abort(BDRVReopenState *reopen_state) -{ - BlockDriver *drv; - - assert(reopen_state != NULL); - drv = reopen_state->bs->drv; - assert(drv != NULL); - - if (drv->bdrv_reopen_abort) { - drv->bdrv_reopen_abort(reopen_state); - } - - QDECREF(reopen_state->explicit_options); -} - - -static void bdrv_close(BlockDriverState *bs) -{ - BdrvAioNotifier *ban, *ban_next; - - assert(!bs->job); - - /* Disable I/O limits and drain all pending throttled requests */ - if (bs->throttle_state) { - bdrv_io_limits_disable(bs); - } - - bdrv_drained_begin(bs); /* complete I/O */ - bdrv_flush(bs); - bdrv_drain(bs); /* in case flush left pending I/O */ - - bdrv_release_named_dirty_bitmaps(bs); - assert(QLIST_EMPTY(&bs->dirty_bitmaps)); - - if (bs->blk) { - blk_dev_change_media_cb(bs->blk, false); - } - - if (bs->drv) { - BdrvChild *child, *next; - - bs->drv->bdrv_close(bs); - bs->drv = NULL; - - bdrv_set_backing_hd(bs, NULL); - - if (bs->file != NULL) { - bdrv_unref_child(bs, bs->file); - bs->file = NULL; - } - - QLIST_FOREACH_SAFE(child, &bs->children, next, next) { - /* TODO Remove bdrv_unref() from drivers' close function and use - * bdrv_unref_child() here */ - if (child->bs->inherits_from == bs) { - child->bs->inherits_from = NULL; - } - bdrv_detach_child(child); - } - - g_free(bs->opaque); - bs->opaque = NULL; - bs->copy_on_read = 0; - bs->backing_file[0] = '\0'; - bs->backing_format[0] = '\0'; - bs->total_sectors = 0; - bs->encrypted = 0; - bs->valid_key = 0; - bs->sg = 0; - bs->zero_beyond_eof = false; - QDECREF(bs->options); - QDECREF(bs->explicit_options); - bs->options = NULL; - QDECREF(bs->full_open_options); - bs->full_open_options = NULL; - } - - QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { - g_free(ban); - } - QLIST_INIT(&bs->aio_notifiers); - bdrv_drained_end(bs); -} - -void bdrv_close_all(void) -{ - BlockDriverState *bs; - AioContext *aio_context; - - /* Drop references from requests still in flight, such as canceled block - * jobs whose AIO context has not been polled yet */ - bdrv_drain_all(); - - blk_remove_all_bs(); - blockdev_close_all_bdrv_states(); - - /* Cancel all block jobs */ - while (!QTAILQ_EMPTY(&all_bdrv_states)) { - QTAILQ_FOREACH(bs, &all_bdrv_states, bs_list) { - aio_context = bdrv_get_aio_context(bs); - - aio_context_acquire(aio_context); - if (bs->job) { - block_job_cancel_sync(bs->job); - aio_context_release(aio_context); - break; - } - aio_context_release(aio_context); - } - - /* All the remaining BlockDriverStates are referenced directly or - * indirectly from block jobs, so there needs to be at least one BDS - * directly used by a block job */ - assert(bs); - } -} - -/* Fields that need to stay with the top-level BDS */ -static void bdrv_move_feature_fields(BlockDriverState *bs_dest, - BlockDriverState *bs_src) -{ - /* move some fields that need to stay attached to the device */ -} - -static void change_parent_backing_link(BlockDriverState *from, - BlockDriverState *to) -{ - BdrvChild *c, *next; - - if (from->blk) { - /* FIXME We bypass blk_set_bs(), so we need to make these updates - * manually. The root problem is not in this change function, but the - * existence of BlockDriverState.blk. */ - to->blk = from->blk; - from->blk = NULL; - } - - QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { - assert(c->role != &child_backing); - c->bs = to; - QLIST_REMOVE(c, next_parent); - QLIST_INSERT_HEAD(&to->parents, c, next_parent); - bdrv_ref(to); - bdrv_unref(from); - } -} - -static void swap_feature_fields(BlockDriverState *bs_top, - BlockDriverState *bs_new) -{ - BlockDriverState tmp; - - bdrv_move_feature_fields(&tmp, bs_top); - bdrv_move_feature_fields(bs_top, bs_new); - bdrv_move_feature_fields(bs_new, &tmp); - - assert(!bs_new->throttle_state); - if (bs_top->throttle_state) { - assert(bs_top->io_limits_enabled); - bdrv_io_limits_enable(bs_new, throttle_group_get_name(bs_top)); - bdrv_io_limits_disable(bs_top); - } -} - -/* - * Add new bs contents at the top of an image chain while the chain is - * live, while keeping required fields on the top layer. - * - * This will modify the BlockDriverState fields, and swap contents - * between bs_new and bs_top. Both bs_new and bs_top are modified. - * - * bs_new must not be attached to a BlockBackend. - * - * This function does not create any image files. - * - * bdrv_append() takes ownership of a bs_new reference and unrefs it because - * that's what the callers commonly need. bs_new will be referenced by the old - * parents of bs_top after bdrv_append() returns. If the caller needs to keep a - * reference of its own, it must call bdrv_ref(). - */ -void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) -{ - assert(!bdrv_requests_pending(bs_top)); - assert(!bdrv_requests_pending(bs_new)); - - bdrv_ref(bs_top); - change_parent_backing_link(bs_top, bs_new); - - /* Some fields always stay on top of the backing file chain */ - swap_feature_fields(bs_top, bs_new); - - bdrv_set_backing_hd(bs_new, bs_top); - bdrv_unref(bs_top); - - /* bs_new is now referenced by its new parents, we don't need the - * additional reference any more. */ - bdrv_unref(bs_new); -} - -void bdrv_replace_in_backing_chain(BlockDriverState *old, BlockDriverState *new) -{ - assert(!bdrv_requests_pending(old)); - assert(!bdrv_requests_pending(new)); - - bdrv_ref(old); - - if (old->blk) { - /* As long as these fields aren't in BlockBackend, but in the top-level - * BlockDriverState, it's not possible for a BDS to have two BBs. - * - * We really want to copy the fields from old to new, but we go for a - * swap instead so that pointers aren't duplicated and cause trouble. - * (Also, bdrv_swap() used to do the same.) */ - assert(!new->blk); - swap_feature_fields(old, new); - } - change_parent_backing_link(old, new); - - /* Change backing files if a previously independent node is added to the - * chain. For active commit, we replace top by its own (indirect) backing - * file and don't do anything here so we don't build a loop. */ - if (new->backing == NULL && !bdrv_chain_contains(backing_bs(old), new)) { - bdrv_set_backing_hd(new, backing_bs(old)); - bdrv_set_backing_hd(old, NULL); - } - - bdrv_unref(old); -} - -static void bdrv_delete(BlockDriverState *bs) -{ - assert(!bs->job); - assert(bdrv_op_blocker_is_empty(bs)); - assert(!bs->refcnt); - - bdrv_close(bs); - - /* remove from list, if necessary */ - if (bs->node_name[0] != '\0') { - QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list); - } - QTAILQ_REMOVE(&all_bdrv_states, bs, bs_list); - - g_free(bs); -} - -/* - * Run consistency checks on an image - * - * Returns 0 if the check could be completed (it doesn't mean that the image is - * free of errors) or -errno when an internal error occurred. The results of the - * check are stored in res. - */ -int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) -{ - if (bs->drv == NULL) { - return -ENOMEDIUM; - } - if (bs->drv->bdrv_check == NULL) { - return -ENOTSUP; - } - - memset(res, 0, sizeof(*res)); - return bs->drv->bdrv_check(bs, res, fix); -} - -#define COMMIT_BUF_SECTORS 2048 - -/* commit COW file into the raw image */ -int bdrv_commit(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - int64_t sector, total_sectors, length, backing_length; - int n, ro, open_flags; - int ret = 0; - uint8_t *buf = NULL; - - if (!drv) - return -ENOMEDIUM; - - if (!bs->backing) { - return -ENOTSUP; - } - - if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, NULL) || - bdrv_op_is_blocked(bs->backing->bs, BLOCK_OP_TYPE_COMMIT_TARGET, NULL)) { - return -EBUSY; - } - - ro = bs->backing->bs->read_only; - open_flags = bs->backing->bs->open_flags; - - if (ro) { - if (bdrv_reopen(bs->backing->bs, open_flags | BDRV_O_RDWR, NULL)) { - return -EACCES; - } - } - - length = bdrv_getlength(bs); - if (length < 0) { - ret = length; - goto ro_cleanup; - } - - backing_length = bdrv_getlength(bs->backing->bs); - if (backing_length < 0) { - ret = backing_length; - goto ro_cleanup; - } - - /* If our top snapshot is larger than the backing file image, - * grow the backing file image if possible. If not possible, - * we must return an error */ - if (length > backing_length) { - ret = bdrv_truncate(bs->backing->bs, length); - if (ret < 0) { - goto ro_cleanup; - } - } - - total_sectors = length >> BDRV_SECTOR_BITS; - - /* qemu_try_blockalign() for bs will choose an alignment that works for - * bs->backing->bs as well, so no need to compare the alignment manually. */ - buf = qemu_try_blockalign(bs, COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE); - if (buf == NULL) { - ret = -ENOMEM; - goto ro_cleanup; - } - - for (sector = 0; sector < total_sectors; sector += n) { - ret = bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n); - if (ret < 0) { - goto ro_cleanup; - } - if (ret) { - ret = bdrv_read(bs, sector, buf, n); - if (ret < 0) { - goto ro_cleanup; - } - - ret = bdrv_write(bs->backing->bs, sector, buf, n); - if (ret < 0) { - goto ro_cleanup; - } - } - } - - if (drv->bdrv_make_empty) { - ret = drv->bdrv_make_empty(bs); - if (ret < 0) { - goto ro_cleanup; - } - bdrv_flush(bs); - } - - /* - * Make sure all data we wrote to the backing device is actually - * stable on disk. - */ - if (bs->backing) { - bdrv_flush(bs->backing->bs); - } - - ret = 0; -ro_cleanup: - qemu_vfree(buf); - - if (ro) { - /* ignoring error return here */ - bdrv_reopen(bs->backing->bs, open_flags & ~BDRV_O_RDWR, NULL); - } - - return ret; -} - -/* - * Return values: - * 0 - success - * -EINVAL - backing format specified, but no file - * -ENOSPC - can't update the backing file because no space is left in the - * image file header - * -ENOTSUP - format driver doesn't support changing the backing file - */ -int bdrv_change_backing_file(BlockDriverState *bs, - const char *backing_file, const char *backing_fmt) -{ - BlockDriver *drv = bs->drv; - int ret; - - /* Backing file format doesn't make sense without a backing file */ - if (backing_fmt && !backing_file) { - return -EINVAL; - } - - if (drv->bdrv_change_backing_file != NULL) { - ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); - } else { - ret = -ENOTSUP; - } - - if (ret == 0) { - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); - } - return ret; -} - -/* - * Finds the image layer in the chain that has 'bs' as its backing file. - * - * active is the current topmost image. - * - * Returns NULL if bs is not found in active's image chain, - * or if active == bs. - * - * Returns the bottommost base image if bs == NULL. - */ -BlockDriverState *bdrv_find_overlay(BlockDriverState *active, - BlockDriverState *bs) -{ - while (active && bs != backing_bs(active)) { - active = backing_bs(active); - } - - return active; -} - -/* Given a BDS, searches for the base layer. */ -BlockDriverState *bdrv_find_base(BlockDriverState *bs) -{ - return bdrv_find_overlay(bs, NULL); -} - -/* - * Drops images above 'base' up to and including 'top', and sets the image - * above 'top' to have base as its backing file. - * - * Requires that the overlay to 'top' is opened r/w, so that the backing file - * information in 'bs' can be properly updated. - * - * E.g., this will convert the following chain: - * bottom <- base <- intermediate <- top <- active - * - * to - * - * bottom <- base <- active - * - * It is allowed for bottom==base, in which case it converts: - * - * base <- intermediate <- top <- active - * - * to - * - * base <- active - * - * If backing_file_str is non-NULL, it will be used when modifying top's - * overlay image metadata. - * - * Error conditions: - * if active == top, that is considered an error - * - */ -int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top, - BlockDriverState *base, const char *backing_file_str) -{ - BlockDriverState *new_top_bs = NULL; - int ret = -EIO; - - if (!top->drv || !base->drv) { - goto exit; - } - - new_top_bs = bdrv_find_overlay(active, top); - - if (new_top_bs == NULL) { - /* we could not find the image above 'top', this is an error */ - goto exit; - } - - /* special case of new_top_bs->backing->bs already pointing to base - nothing - * to do, no intermediate images */ - if (backing_bs(new_top_bs) == base) { - ret = 0; - goto exit; - } - - /* Make sure that base is in the backing chain of top */ - if (!bdrv_chain_contains(top, base)) { - goto exit; - } - - /* success - we can delete the intermediate states, and link top->base */ - backing_file_str = backing_file_str ? backing_file_str : base->filename; - ret = bdrv_change_backing_file(new_top_bs, backing_file_str, - base->drv ? base->drv->format_name : ""); - if (ret) { - goto exit; - } - bdrv_set_backing_hd(new_top_bs, base); - - ret = 0; -exit: - return ret; -} - -/** - * Truncate file to 'offset' bytes (needed only for file protocols) - */ -int bdrv_truncate(BlockDriverState *bs, int64_t offset) -{ - BlockDriver *drv = bs->drv; - int ret; - if (!drv) - return -ENOMEDIUM; - if (!drv->bdrv_truncate) - return -ENOTSUP; - if (bs->read_only) - return -EACCES; - - ret = drv->bdrv_truncate(bs, offset); - if (ret == 0) { - ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); - bdrv_dirty_bitmap_truncate(bs); - if (bs->blk) { - blk_dev_resize_cb(bs->blk); - } - } - return ret; -} - -/** - * Length of a allocated file in bytes. Sparse files are counted by actual - * allocated space. Return < 0 if error or unknown. - */ -int64_t bdrv_get_allocated_file_size(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - if (!drv) { - return -ENOMEDIUM; - } - if (drv->bdrv_get_allocated_file_size) { - return drv->bdrv_get_allocated_file_size(bs); - } - if (bs->file) { - return bdrv_get_allocated_file_size(bs->file->bs); - } - return -ENOTSUP; -} - -/** - * Return number of sectors on success, -errno on error. - */ -int64_t bdrv_nb_sectors(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - - if (!drv) - return -ENOMEDIUM; - - if (drv->has_variable_length) { - int ret = refresh_total_sectors(bs, bs->total_sectors); - if (ret < 0) { - return ret; - } - } - return bs->total_sectors; -} - -/** - * Return length in bytes on success, -errno on error. - * The length is always a multiple of BDRV_SECTOR_SIZE. - */ -int64_t bdrv_getlength(BlockDriverState *bs) -{ - int64_t ret = bdrv_nb_sectors(bs); - - ret = ret > INT64_MAX / BDRV_SECTOR_SIZE ? -EFBIG : ret; - return ret < 0 ? ret : ret * BDRV_SECTOR_SIZE; -} - -/* return 0 as number of sectors if no device present or error */ -void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) -{ - int64_t nb_sectors = bdrv_nb_sectors(bs); - - *nb_sectors_ptr = nb_sectors < 0 ? 0 : nb_sectors; -} - -int bdrv_is_read_only(BlockDriverState *bs) -{ - return bs->read_only; -} - -int bdrv_is_sg(BlockDriverState *bs) -{ - return bs->sg; -} - -int bdrv_is_encrypted(BlockDriverState *bs) -{ - if (bs->backing && bs->backing->bs->encrypted) { - return 1; - } - return bs->encrypted; -} - -int bdrv_key_required(BlockDriverState *bs) -{ - BdrvChild *backing = bs->backing; - - if (backing && backing->bs->encrypted && !backing->bs->valid_key) { - return 1; - } - return (bs->encrypted && !bs->valid_key); -} - -int bdrv_set_key(BlockDriverState *bs, const char *key) -{ - int ret; - if (bs->backing && bs->backing->bs->encrypted) { - ret = bdrv_set_key(bs->backing->bs, key); - if (ret < 0) - return ret; - if (!bs->encrypted) - return 0; - } - if (!bs->encrypted) { - return -EINVAL; - } else if (!bs->drv || !bs->drv->bdrv_set_key) { - return -ENOMEDIUM; - } - ret = bs->drv->bdrv_set_key(bs, key); - if (ret < 0) { - bs->valid_key = 0; - } else if (!bs->valid_key) { - bs->valid_key = 1; - if (bs->blk) { - /* call the change callback now, we skipped it on open */ - blk_dev_change_media_cb(bs->blk, true); - } - } - return ret; -} - -/* - * Provide an encryption key for @bs. - * If @key is non-null: - * If @bs is not encrypted, fail. - * Else if the key is invalid, fail. - * Else set @bs's key to @key, replacing the existing key, if any. - * If @key is null: - * If @bs is encrypted and still lacks a key, fail. - * Else do nothing. - * On failure, store an error object through @errp if non-null. - */ -void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp) -{ - if (key) { - if (!bdrv_is_encrypted(bs)) { - error_setg(errp, "Node '%s' is not encrypted", - bdrv_get_device_or_node_name(bs)); - } else if (bdrv_set_key(bs, key) < 0) { - error_setg(errp, QERR_INVALID_PASSWORD); - } - } else { - if (bdrv_key_required(bs)) { - error_set(errp, ERROR_CLASS_DEVICE_ENCRYPTED, - "'%s' (%s) is encrypted", - bdrv_get_device_or_node_name(bs), - bdrv_get_encrypted_filename(bs)); - } - } -} - -const char *bdrv_get_format_name(BlockDriverState *bs) -{ - return bs->drv ? bs->drv->format_name : NULL; -} - -static int qsort_strcmp(const void *a, const void *b) -{ - return strcmp(a, b); -} - -void bdrv_iterate_format(void (*it)(void *opaque, const char *name), - void *opaque) -{ - BlockDriver *drv; - int count = 0; - int i; - const char **formats = NULL; - - QLIST_FOREACH(drv, &bdrv_drivers, list) { - if (drv->format_name) { - bool found = false; - int i = count; - while (formats && i && !found) { - found = !strcmp(formats[--i], drv->format_name); - } - - if (!found) { - formats = g_renew(const char *, formats, count + 1); - formats[count++] = drv->format_name; - } - } - } - - qsort(formats, count, sizeof(formats[0]), qsort_strcmp); - - for (i = 0; i < count; i++) { - it(opaque, formats[i]); - } - - g_free(formats); -} - -/* This function is to find a node in the bs graph */ -BlockDriverState *bdrv_find_node(const char *node_name) -{ - BlockDriverState *bs; - - assert(node_name); - - QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { - if (!strcmp(node_name, bs->node_name)) { - return bs; - } - } - return NULL; -} - -/* Put this QMP function here so it can access the static graph_bdrv_states. */ -BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp) -{ - BlockDeviceInfoList *list, *entry; - BlockDriverState *bs; - - list = NULL; - QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { - BlockDeviceInfo *info = bdrv_block_device_info(NULL, bs, errp); - if (!info) { - qapi_free_BlockDeviceInfoList(list); - return NULL; - } - entry = g_malloc0(sizeof(*entry)); - entry->value = info; - entry->next = list; - list = entry; - } - - return list; -} - -BlockDriverState *bdrv_lookup_bs(const char *device, - const char *node_name, - Error **errp) -{ - BlockBackend *blk; - BlockDriverState *bs; - - if (device) { - blk = blk_by_name(device); - - if (blk) { - bs = blk_bs(blk); - if (!bs) { - error_setg(errp, "Device '%s' has no medium", device); - } - - return bs; - } - } - - if (node_name) { - bs = bdrv_find_node(node_name); - - if (bs) { - return bs; - } - } - - error_setg(errp, "Cannot find device=%s nor node_name=%s", - device ? device : "", - node_name ? node_name : ""); - return NULL; -} - -/* If 'base' is in the same chain as 'top', return true. Otherwise, - * return false. If either argument is NULL, return false. */ -bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base) -{ - while (top && top != base) { - top = backing_bs(top); - } - - return top != NULL; -} - -BlockDriverState *bdrv_next_node(BlockDriverState *bs) -{ - if (!bs) { - return QTAILQ_FIRST(&graph_bdrv_states); - } - return QTAILQ_NEXT(bs, node_list); -} - -/* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by - * the monitor or attached to a BlockBackend */ -BlockDriverState *bdrv_next(BlockDriverState *bs) -{ - if (!bs || bs->blk) { - bs = blk_next_root_bs(bs); - if (bs) { - return bs; - } - } - - /* Ignore all BDSs that are attached to a BlockBackend here; they have been - * handled by the above block already */ - do { - bs = bdrv_next_monitor_owned(bs); - } while (bs && bs->blk); - return bs; -} - -const char *bdrv_get_node_name(const BlockDriverState *bs) -{ - return bs->node_name; -} - -/* TODO check what callers really want: bs->node_name or blk_name() */ -const char *bdrv_get_device_name(const BlockDriverState *bs) -{ - return bs->blk ? blk_name(bs->blk) : ""; -} - -/* This can be used to identify nodes that might not have a device - * name associated. Since node and device names live in the same - * namespace, the result is unambiguous. The exception is if both are - * absent, then this returns an empty (non-null) string. */ -const char *bdrv_get_device_or_node_name(const BlockDriverState *bs) -{ - return bs->blk ? blk_name(bs->blk) : bs->node_name; -} - -int bdrv_get_flags(BlockDriverState *bs) -{ - return bs->open_flags; -} - -int bdrv_has_zero_init_1(BlockDriverState *bs) -{ - return 1; -} - -int bdrv_has_zero_init(BlockDriverState *bs) -{ - assert(bs->drv); - - /* If BS is a copy on write image, it is initialized to - the contents of the base image, which may not be zeroes. */ - if (bs->backing) { - return 0; - } - if (bs->drv->bdrv_has_zero_init) { - return bs->drv->bdrv_has_zero_init(bs); - } - - /* safe default */ - return 0; -} - -bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs) -{ - BlockDriverInfo bdi; - - if (bs->backing) { - return false; - } - - if (bdrv_get_info(bs, &bdi) == 0) { - return bdi.unallocated_blocks_are_zero; - } - - return false; -} - -bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs) -{ - BlockDriverInfo bdi; - - if (bs->backing || !(bs->open_flags & BDRV_O_UNMAP)) { - return false; - } - - if (bdrv_get_info(bs, &bdi) == 0) { - return bdi.can_write_zeroes_with_unmap; - } - - return false; -} - -const char *bdrv_get_encrypted_filename(BlockDriverState *bs) -{ - if (bs->backing && bs->backing->bs->encrypted) - return bs->backing_file; - else if (bs->encrypted) - return bs->filename; - else - return NULL; -} - -void bdrv_get_backing_filename(BlockDriverState *bs, - char *filename, int filename_size) -{ - pstrcpy(filename, filename_size, bs->backing_file); -} - -int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) -{ - BlockDriver *drv = bs->drv; - if (!drv) - return -ENOMEDIUM; - if (!drv->bdrv_get_info) - return -ENOTSUP; - memset(bdi, 0, sizeof(*bdi)); - return drv->bdrv_get_info(bs, bdi); -} - -ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - if (drv && drv->bdrv_get_specific_info) { - return drv->bdrv_get_specific_info(bs); - } - return NULL; -} - -void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event) -{ - if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) { - return; - } - - bs->drv->bdrv_debug_event(bs, event); -} - -int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, - const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) { - bs = bs->file ? bs->file->bs : NULL; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) { - return bs->drv->bdrv_debug_breakpoint(bs, event, tag); - } - - return -ENOTSUP; -} - -int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) { - bs = bs->file ? bs->file->bs : NULL; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) { - return bs->drv->bdrv_debug_remove_breakpoint(bs, tag); - } - - return -ENOTSUP; -} - -int bdrv_debug_resume(BlockDriverState *bs, const char *tag) -{ - while (bs && (!bs->drv || !bs->drv->bdrv_debug_resume)) { - bs = bs->file ? bs->file->bs : NULL; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_resume) { - return bs->drv->bdrv_debug_resume(bs, tag); - } - - return -ENOTSUP; -} - -bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) { - bs = bs->file ? bs->file->bs : NULL; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) { - return bs->drv->bdrv_debug_is_suspended(bs, tag); - } - - return false; -} - -int bdrv_is_snapshot(BlockDriverState *bs) -{ - return !!(bs->open_flags & BDRV_O_SNAPSHOT); -} - -/* backing_file can either be relative, or absolute, or a protocol. If it is - * relative, it must be relative to the chain. So, passing in bs->filename - * from a BDS as backing_file should not be done, as that may be relative to - * the CWD rather than the chain. */ -BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, - const char *backing_file) -{ - char *filename_full = NULL; - char *backing_file_full = NULL; - char *filename_tmp = NULL; - int is_protocol = 0; - BlockDriverState *curr_bs = NULL; - BlockDriverState *retval = NULL; - - if (!bs || !bs->drv || !backing_file) { - return NULL; - } - - filename_full = g_malloc(PATH_MAX); - backing_file_full = g_malloc(PATH_MAX); - filename_tmp = g_malloc(PATH_MAX); - - is_protocol = path_has_protocol(backing_file); - - for (curr_bs = bs; curr_bs->backing; curr_bs = curr_bs->backing->bs) { - - /* If either of the filename paths is actually a protocol, then - * compare unmodified paths; otherwise make paths relative */ - if (is_protocol || path_has_protocol(curr_bs->backing_file)) { - if (strcmp(backing_file, curr_bs->backing_file) == 0) { - retval = curr_bs->backing->bs; - break; - } - } else { - /* If not an absolute filename path, make it relative to the current - * image's filename path */ - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - backing_file); - - /* We are going to compare absolute pathnames */ - if (!realpath(filename_tmp, filename_full)) { - continue; - } - - /* We need to make sure the backing filename we are comparing against - * is relative to the current image filename (or absolute) */ - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - curr_bs->backing_file); - - if (!realpath(filename_tmp, backing_file_full)) { - continue; - } - - if (strcmp(backing_file_full, filename_full) == 0) { - retval = curr_bs->backing->bs; - break; - } - } - } - - g_free(filename_full); - g_free(backing_file_full); - g_free(filename_tmp); - return retval; -} - -int bdrv_get_backing_file_depth(BlockDriverState *bs) -{ - if (!bs->drv) { - return 0; - } - - if (!bs->backing) { - return 0; - } - - return 1 + bdrv_get_backing_file_depth(bs->backing->bs); -} - -void bdrv_init(void) -{ - module_call_init(MODULE_INIT_BLOCK); -} - -void bdrv_init_with_whitelist(void) -{ - use_bdrv_whitelist = 1; - bdrv_init(); -} - -void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp) -{ - Error *local_err = NULL; - int ret; - - if (!bs->drv) { - return; - } - - if (!(bs->open_flags & BDRV_O_INACTIVE)) { - return; - } - bs->open_flags &= ~BDRV_O_INACTIVE; - - if (bs->drv->bdrv_invalidate_cache) { - bs->drv->bdrv_invalidate_cache(bs, &local_err); - } else if (bs->file) { - bdrv_invalidate_cache(bs->file->bs, &local_err); - } - if (local_err) { - bs->open_flags |= BDRV_O_INACTIVE; - error_propagate(errp, local_err); - return; - } - - ret = refresh_total_sectors(bs, bs->total_sectors); - if (ret < 0) { - bs->open_flags |= BDRV_O_INACTIVE; - error_setg_errno(errp, -ret, "Could not refresh total sector count"); - return; - } -} - -void bdrv_invalidate_cache_all(Error **errp) -{ - BlockDriverState *bs = NULL; - Error *local_err = NULL; - - while ((bs = bdrv_next(bs)) != NULL) { - AioContext *aio_context = bdrv_get_aio_context(bs); - - aio_context_acquire(aio_context); - bdrv_invalidate_cache(bs, &local_err); - aio_context_release(aio_context); - if (local_err) { - error_propagate(errp, local_err); - return; - } - } -} - -static int bdrv_inactivate(BlockDriverState *bs) -{ - int ret; - - if (bs->drv->bdrv_inactivate) { - ret = bs->drv->bdrv_inactivate(bs); - if (ret < 0) { - return ret; - } - } - - bs->open_flags |= BDRV_O_INACTIVE; - return 0; -} - -int bdrv_inactivate_all(void) -{ - BlockDriverState *bs = NULL; - int ret; - - while ((bs = bdrv_next(bs)) != NULL) { - AioContext *aio_context = bdrv_get_aio_context(bs); - - aio_context_acquire(aio_context); - ret = bdrv_inactivate(bs); - aio_context_release(aio_context); - if (ret < 0) { - return ret; - } - } - - return 0; -} - -/**************************************************************/ -/* removable device support */ - -/** - * Return TRUE if the media is present - */ -bool bdrv_is_inserted(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - BdrvChild *child; - - if (!drv) { - return false; - } - if (drv->bdrv_is_inserted) { - return drv->bdrv_is_inserted(bs); - } - QLIST_FOREACH(child, &bs->children, next) { - if (!bdrv_is_inserted(child->bs)) { - return false; - } - } - return true; -} - -/** - * Return whether the media changed since the last call to this - * function, or -ENOTSUP if we don't know. Most drivers don't know. - */ -int bdrv_media_changed(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_media_changed) { - return drv->bdrv_media_changed(bs); - } - return -ENOTSUP; -} - -/** - * If eject_flag is TRUE, eject the media. Otherwise, close the tray - */ -void bdrv_eject(BlockDriverState *bs, bool eject_flag) -{ - BlockDriver *drv = bs->drv; - const char *device_name; - - if (drv && drv->bdrv_eject) { - drv->bdrv_eject(bs, eject_flag); - } - - device_name = bdrv_get_device_name(bs); - if (device_name[0] != '\0') { - qapi_event_send_device_tray_moved(device_name, - eject_flag, &error_abort); - } -} - -/** - * Lock or unlock the media (if it is locked, the user won't be able - * to eject it manually). - */ -void bdrv_lock_medium(BlockDriverState *bs, bool locked) -{ - BlockDriver *drv = bs->drv; - - trace_bdrv_lock_medium(bs, locked); - - if (drv && drv->bdrv_lock_medium) { - drv->bdrv_lock_medium(bs, locked); - } -} - -/* Get a reference to bs */ -void bdrv_ref(BlockDriverState *bs) -{ - bs->refcnt++; -} - -/* Release a previously grabbed reference to bs. - * If after releasing, reference count is zero, the BlockDriverState is - * deleted. */ -void bdrv_unref(BlockDriverState *bs) -{ - if (!bs) { - return; - } - assert(bs->refcnt > 0); - if (--bs->refcnt == 0) { - bdrv_delete(bs); - } -} - -struct BdrvOpBlocker { - Error *reason; - QLIST_ENTRY(BdrvOpBlocker) list; -}; - -bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp) -{ - BdrvOpBlocker *blocker; - assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); - if (!QLIST_EMPTY(&bs->op_blockers[op])) { - blocker = QLIST_FIRST(&bs->op_blockers[op]); - if (errp) { - *errp = error_copy(blocker->reason); - error_prepend(errp, "Node '%s' is busy: ", - bdrv_get_device_or_node_name(bs)); - } - return true; - } - return false; -} - -void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason) -{ - BdrvOpBlocker *blocker; - assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); - - blocker = g_new0(BdrvOpBlocker, 1); - blocker->reason = reason; - QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list); -} - -void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason) -{ - BdrvOpBlocker *blocker, *next; - assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); - QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) { - if (blocker->reason == reason) { - QLIST_REMOVE(blocker, list); - g_free(blocker); - } - } -} - -void bdrv_op_block_all(BlockDriverState *bs, Error *reason) -{ - int i; - for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { - bdrv_op_block(bs, i, reason); - } -} - -void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason) -{ - int i; - for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { - bdrv_op_unblock(bs, i, reason); - } -} - -bool bdrv_op_blocker_is_empty(BlockDriverState *bs) -{ - int i; - - for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { - if (!QLIST_EMPTY(&bs->op_blockers[i])) { - return false; - } - } - return true; -} - -void bdrv_img_create(const char *filename, const char *fmt, - const char *base_filename, const char *base_fmt, - char *options, uint64_t img_size, int flags, - Error **errp, bool quiet) -{ - QemuOptsList *create_opts = NULL; - QemuOpts *opts = NULL; - const char *backing_fmt, *backing_file; - int64_t size; - BlockDriver *drv, *proto_drv; - Error *local_err = NULL; - int ret = 0; - - /* Find driver and parse its options */ - drv = bdrv_find_format(fmt); - if (!drv) { - error_setg(errp, "Unknown file format '%s'", fmt); - return; - } - - proto_drv = bdrv_find_protocol(filename, true, errp); - if (!proto_drv) { - return; - } - - if (!drv->create_opts) { - error_setg(errp, "Format driver '%s' does not support image creation", - drv->format_name); - return; - } - - if (!proto_drv->create_opts) { - error_setg(errp, "Protocol driver '%s' does not support image creation", - proto_drv->format_name); - return; - } - - create_opts = qemu_opts_append(create_opts, drv->create_opts); - create_opts = qemu_opts_append(create_opts, proto_drv->create_opts); - - /* Create parameter list with default values */ - opts = qemu_opts_create(create_opts, NULL, 0, &error_abort); - qemu_opt_set_number(opts, BLOCK_OPT_SIZE, img_size, &error_abort); - - /* Parse -o options */ - if (options) { - qemu_opts_do_parse(opts, options, NULL, &local_err); - if (local_err) { - error_report_err(local_err); - local_err = NULL; - error_setg(errp, "Invalid options for file format '%s'", fmt); - goto out; - } - } - - if (base_filename) { - qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, &local_err); - if (local_err) { - error_setg(errp, "Backing file not supported for file format '%s'", - fmt); - goto out; - } - } - - if (base_fmt) { - qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, &local_err); - if (local_err) { - error_setg(errp, "Backing file format not supported for file " - "format '%s'", fmt); - goto out; - } - } - - backing_file = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE); - if (backing_file) { - if (!strcmp(filename, backing_file)) { - error_setg(errp, "Error: Trying to create an image with the " - "same filename as the backing file"); - goto out; - } - } - - backing_fmt = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT); - - // The size for the image must always be specified, with one exception: - // If we are using a backing file, we can obtain the size from there - size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0); - if (size == -1) { - if (backing_file) { - BlockDriverState *bs; - char *full_backing = g_new0(char, PATH_MAX); - int64_t size; - int back_flags; - QDict *backing_options = NULL; - - bdrv_get_full_backing_filename_from_filename(filename, backing_file, - full_backing, PATH_MAX, - &local_err); - if (local_err) { - g_free(full_backing); - goto out; - } - - /* backing files always opened read-only */ - back_flags = flags; - back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); - - if (backing_fmt) { - backing_options = qdict_new(); - qdict_put(backing_options, "driver", - qstring_from_str(backing_fmt)); - } - - bs = NULL; - ret = bdrv_open(&bs, full_backing, NULL, backing_options, - back_flags, &local_err); - g_free(full_backing); - if (ret < 0) { - goto out; - } - size = bdrv_getlength(bs); - if (size < 0) { - error_setg_errno(errp, -size, "Could not get size of '%s'", - backing_file); - bdrv_unref(bs); - goto out; - } - - qemu_opt_set_number(opts, BLOCK_OPT_SIZE, size, &error_abort); - - bdrv_unref(bs); - } else { - error_setg(errp, "Image creation needs a size parameter"); - goto out; - } - } - - if (!quiet) { - printf("Formatting '%s', fmt=%s ", filename, fmt); - qemu_opts_print(opts, " "); - puts(""); - } - - ret = bdrv_create(drv, filename, opts, &local_err); - - if (ret == -EFBIG) { - /* This is generally a better message than whatever the driver would - * deliver (especially because of the cluster_size_hint), since that - * is most probably not much different from "image too large". */ - const char *cluster_size_hint = ""; - if (qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE, 0)) { - cluster_size_hint = " (try using a larger cluster size)"; - } - error_setg(errp, "The image size is too large for file format '%s'" - "%s", fmt, cluster_size_hint); - error_free(local_err); - local_err = NULL; - } - -out: - qemu_opts_del(opts); - qemu_opts_free(create_opts); - if (local_err) { - error_propagate(errp, local_err); - } -} - -AioContext *bdrv_get_aio_context(BlockDriverState *bs) -{ - return bs->aio_context; -} - -void bdrv_detach_aio_context(BlockDriverState *bs) -{ - BdrvAioNotifier *baf; - - if (!bs->drv) { - return; - } - - QLIST_FOREACH(baf, &bs->aio_notifiers, list) { - baf->detach_aio_context(baf->opaque); - } - - if (bs->throttle_state) { - throttle_timers_detach_aio_context(&bs->throttle_timers); - } - if (bs->drv->bdrv_detach_aio_context) { - bs->drv->bdrv_detach_aio_context(bs); - } - if (bs->file) { - bdrv_detach_aio_context(bs->file->bs); - } - if (bs->backing) { - bdrv_detach_aio_context(bs->backing->bs); - } - - bs->aio_context = NULL; -} - -void bdrv_attach_aio_context(BlockDriverState *bs, - AioContext *new_context) -{ - BdrvAioNotifier *ban; - - if (!bs->drv) { - return; - } - - bs->aio_context = new_context; - - if (bs->backing) { - bdrv_attach_aio_context(bs->backing->bs, new_context); - } - if (bs->file) { - bdrv_attach_aio_context(bs->file->bs, new_context); - } - if (bs->drv->bdrv_attach_aio_context) { - bs->drv->bdrv_attach_aio_context(bs, new_context); - } - if (bs->throttle_state) { - throttle_timers_attach_aio_context(&bs->throttle_timers, new_context); - } - - QLIST_FOREACH(ban, &bs->aio_notifiers, list) { - ban->attached_aio_context(new_context, ban->opaque); - } -} - -void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context) -{ - bdrv_drain(bs); /* ensure there are no in-flight requests */ - - bdrv_detach_aio_context(bs); - - /* This function executes in the old AioContext so acquire the new one in - * case it runs in a different thread. - */ - aio_context_acquire(new_context); - bdrv_attach_aio_context(bs, new_context); - aio_context_release(new_context); -} - -void bdrv_add_aio_context_notifier(BlockDriverState *bs, - void (*attached_aio_context)(AioContext *new_context, void *opaque), - void (*detach_aio_context)(void *opaque), void *opaque) -{ - BdrvAioNotifier *ban = g_new(BdrvAioNotifier, 1); - *ban = (BdrvAioNotifier){ - .attached_aio_context = attached_aio_context, - .detach_aio_context = detach_aio_context, - .opaque = opaque - }; - - QLIST_INSERT_HEAD(&bs->aio_notifiers, ban, list); -} - -void bdrv_remove_aio_context_notifier(BlockDriverState *bs, - void (*attached_aio_context)(AioContext *, - void *), - void (*detach_aio_context)(void *), - void *opaque) -{ - BdrvAioNotifier *ban, *ban_next; - - QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { - if (ban->attached_aio_context == attached_aio_context && - ban->detach_aio_context == detach_aio_context && - ban->opaque == opaque) - { - QLIST_REMOVE(ban, list); - g_free(ban); - - return; - } - } - - abort(); -} - -int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts, - BlockDriverAmendStatusCB *status_cb, void *cb_opaque) -{ - if (!bs->drv->bdrv_amend_options) { - return -ENOTSUP; - } - return bs->drv->bdrv_amend_options(bs, opts, status_cb, cb_opaque); -} - -/* This function will be called by the bdrv_recurse_is_first_non_filter method - * of block filter and by bdrv_is_first_non_filter. - * It is used to test if the given bs is the candidate or recurse more in the - * node graph. - */ -bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, - BlockDriverState *candidate) -{ - /* return false if basic checks fails */ - if (!bs || !bs->drv) { - return false; - } - - /* the code reached a non block filter driver -> check if the bs is - * the same as the candidate. It's the recursion termination condition. - */ - if (!bs->drv->is_filter) { - return bs == candidate; - } - /* Down this path the driver is a block filter driver */ - - /* If the block filter recursion method is defined use it to recurse down - * the node graph. - */ - if (bs->drv->bdrv_recurse_is_first_non_filter) { - return bs->drv->bdrv_recurse_is_first_non_filter(bs, candidate); - } - - /* the driver is a block filter but don't allow to recurse -> return false - */ - return false; -} - -/* This function checks if the candidate is the first non filter bs down it's - * bs chain. Since we don't have pointers to parents it explore all bs chains - * from the top. Some filters can choose not to pass down the recursion. - */ -bool bdrv_is_first_non_filter(BlockDriverState *candidate) -{ - BlockDriverState *bs = NULL; - - /* walk down the bs forest recursively */ - while ((bs = bdrv_next(bs)) != NULL) { - bool perm; - - /* try to recurse in this top level bs */ - perm = bdrv_recurse_is_first_non_filter(bs, candidate); - - /* candidate is the first non filter */ - if (perm) { - return true; - } - } - - return false; -} - -BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, - const char *node_name, Error **errp) -{ - BlockDriverState *to_replace_bs = bdrv_find_node(node_name); - AioContext *aio_context; - - if (!to_replace_bs) { - error_setg(errp, "Node name '%s' not found", node_name); - return NULL; - } - - aio_context = bdrv_get_aio_context(to_replace_bs); - aio_context_acquire(aio_context); - - if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) { - to_replace_bs = NULL; - goto out; - } - - /* We don't want arbitrary node of the BDS chain to be replaced only the top - * most non filter in order to prevent data corruption. - * Another benefit is that this tests exclude backing files which are - * blocked by the backing blockers. - */ - if (!bdrv_recurse_is_first_non_filter(parent_bs, to_replace_bs)) { - error_setg(errp, "Only top most non filter can be replaced"); - to_replace_bs = NULL; - goto out; - } - -out: - aio_context_release(aio_context); - return to_replace_bs; -} - -static bool append_open_options(QDict *d, BlockDriverState *bs) -{ - const QDictEntry *entry; - QemuOptDesc *desc; - BdrvChild *child; - bool found_any = false; - const char *p; - - for (entry = qdict_first(bs->options); entry; - entry = qdict_next(bs->options, entry)) - { - /* Exclude options for children */ - QLIST_FOREACH(child, &bs->children, next) { - if (strstart(qdict_entry_key(entry), child->name, &p) - && (!*p || *p == '.')) - { - break; - } - } - if (child) { - continue; - } - - /* And exclude all non-driver-specific options */ - for (desc = bdrv_runtime_opts.desc; desc->name; desc++) { - if (!strcmp(qdict_entry_key(entry), desc->name)) { - break; - } - } - if (desc->name) { - continue; - } - - qobject_incref(qdict_entry_value(entry)); - qdict_put_obj(d, qdict_entry_key(entry), qdict_entry_value(entry)); - found_any = true; - } - - return found_any; -} - -/* Updates the following BDS fields: - * - exact_filename: A filename which may be used for opening a block device - * which (mostly) equals the given BDS (even without any - * other options; so reading and writing must return the same - * results, but caching etc. may be different) - * - full_open_options: Options which, when given when opening a block device - * (without a filename), result in a BDS (mostly) - * equalling the given one - * - filename: If exact_filename is set, it is copied here. Otherwise, - * full_open_options is converted to a JSON object, prefixed with - * "json:" (for use through the JSON pseudo protocol) and put here. - */ -void bdrv_refresh_filename(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - QDict *opts; - - if (!drv) { - return; - } - - /* This BDS's file name will most probably depend on its file's name, so - * refresh that first */ - if (bs->file) { - bdrv_refresh_filename(bs->file->bs); - } - - if (drv->bdrv_refresh_filename) { - /* Obsolete information is of no use here, so drop the old file name - * information before refreshing it */ - bs->exact_filename[0] = '\0'; - if (bs->full_open_options) { - QDECREF(bs->full_open_options); - bs->full_open_options = NULL; - } - - opts = qdict_new(); - append_open_options(opts, bs); - drv->bdrv_refresh_filename(bs, opts); - QDECREF(opts); - } else if (bs->file) { - /* Try to reconstruct valid information from the underlying file */ - bool has_open_options; - - bs->exact_filename[0] = '\0'; - if (bs->full_open_options) { - QDECREF(bs->full_open_options); - bs->full_open_options = NULL; - } - - opts = qdict_new(); - has_open_options = append_open_options(opts, bs); - - /* If no specific options have been given for this BDS, the filename of - * the underlying file should suffice for this one as well */ - if (bs->file->bs->exact_filename[0] && !has_open_options) { - strcpy(bs->exact_filename, bs->file->bs->exact_filename); - } - /* Reconstructing the full options QDict is simple for most format block - * drivers, as long as the full options are known for the underlying - * file BDS. The full options QDict of that file BDS should somehow - * contain a representation of the filename, therefore the following - * suffices without querying the (exact_)filename of this BDS. */ - if (bs->file->bs->full_open_options) { - qdict_put_obj(opts, "driver", - QOBJECT(qstring_from_str(drv->format_name))); - QINCREF(bs->file->bs->full_open_options); - qdict_put_obj(opts, "file", - QOBJECT(bs->file->bs->full_open_options)); - - bs->full_open_options = opts; - } else { - QDECREF(opts); - } - } else if (!bs->full_open_options && qdict_size(bs->options)) { - /* There is no underlying file BDS (at least referenced by BDS.file), - * so the full options QDict should be equal to the options given - * specifically for this block device when it was opened (plus the - * driver specification). - * Because those options don't change, there is no need to update - * full_open_options when it's already set. */ - - opts = qdict_new(); - append_open_options(opts, bs); - qdict_put_obj(opts, "driver", - QOBJECT(qstring_from_str(drv->format_name))); - - if (bs->exact_filename[0]) { - /* This may not work for all block protocol drivers (some may - * require this filename to be parsed), but we have to find some - * default solution here, so just include it. If some block driver - * does not support pure options without any filename at all or - * needs some special format of the options QDict, it needs to - * implement the driver-specific bdrv_refresh_filename() function. - */ - qdict_put_obj(opts, "filename", - QOBJECT(qstring_from_str(bs->exact_filename))); - } - - bs->full_open_options = opts; - } - - if (bs->exact_filename[0]) { - pstrcpy(bs->filename, sizeof(bs->filename), bs->exact_filename); - } else if (bs->full_open_options) { - QString *json = qobject_to_json(QOBJECT(bs->full_open_options)); - snprintf(bs->filename, sizeof(bs->filename), "json:%s", - qstring_get_str(json)); - QDECREF(json); - } -} |