File:  [Qemu by Fabrice Bellard] / qemu / block.c
Revision 1.1.1.19 (vendor branch): download - view: text, annotated - select for diffs
Tue Apr 24 18:34:00 2018 UTC (19 months, 2 weeks ago) by root
Branches: qemu, MAIN
CVS tags: qemu0140, HEAD
qemu 0.14.0

    1: /*
    2:  * QEMU System Emulator block driver
    3:  *
    4:  * Copyright (c) 2003 Fabrice Bellard
    5:  *
    6:  * Permission is hereby granted, free of charge, to any person obtaining a copy
    7:  * of this software and associated documentation files (the "Software"), to deal
    8:  * in the Software without restriction, including without limitation the rights
    9:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   10:  * copies of the Software, and to permit persons to whom the Software is
   11:  * furnished to do so, subject to the following conditions:
   12:  *
   13:  * The above copyright notice and this permission notice shall be included in
   14:  * all copies or substantial portions of the Software.
   15:  *
   16:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   17:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   18:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
   19:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   20:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   21:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   22:  * THE SOFTWARE.
   23:  */
   24: #include "config-host.h"
   25: #include "qemu-common.h"
   26: #include "trace.h"
   27: #include "monitor.h"
   28: #include "block_int.h"
   29: #include "module.h"
   30: #include "qemu-objects.h"
   31: 
   32: #ifdef CONFIG_BSD
   33: #include <sys/types.h>
   34: #include <sys/stat.h>
   35: #include <sys/ioctl.h>
   36: #include <sys/queue.h>
   37: #ifndef __DragonFly__
   38: #include <sys/disk.h>
   39: #endif
   40: #endif
   41: 
   42: #ifdef _WIN32
   43: #include <windows.h>
   44: #endif
   45: 
   46: static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
   47:         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
   48:         BlockDriverCompletionFunc *cb, void *opaque);
   49: static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
   50:         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
   51:         BlockDriverCompletionFunc *cb, void *opaque);
   52: static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
   53:         BlockDriverCompletionFunc *cb, void *opaque);
   54: static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs,
   55:         BlockDriverCompletionFunc *cb, void *opaque);
   56: static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
   57:                         uint8_t *buf, int nb_sectors);
   58: static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
   59:                          const uint8_t *buf, int nb_sectors);
   60: 
   61: static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
   62:     QTAILQ_HEAD_INITIALIZER(bdrv_states);
   63: 
   64: static QLIST_HEAD(, BlockDriver) bdrv_drivers =
   65:     QLIST_HEAD_INITIALIZER(bdrv_drivers);
   66: 
   67: /* The device to use for VM snapshots */
   68: static BlockDriverState *bs_snapshots;
   69: 
   70: /* If non-zero, use only whitelisted block drivers */
   71: static int use_bdrv_whitelist;
   72: 
   73: #ifdef _WIN32
   74: static int is_windows_drive_prefix(const char *filename)
   75: {
   76:     return (((filename[0] >= 'a' && filename[0] <= 'z') ||
   77:              (filename[0] >= 'A' && filename[0] <= 'Z')) &&
   78:             filename[1] == ':');
   79: }
   80: 
   81: int is_windows_drive(const char *filename)
   82: {
   83:     if (is_windows_drive_prefix(filename) &&
   84:         filename[2] == '\0')
   85:         return 1;
   86:     if (strstart(filename, "\\\\.\\", NULL) ||
   87:         strstart(filename, "//./", NULL))
   88:         return 1;
   89:     return 0;
   90: }
   91: #endif
   92: 
   93: /* check if the path starts with "<protocol>:" */
   94: static int path_has_protocol(const char *path)
   95: {
   96: #ifdef _WIN32
   97:     if (is_windows_drive(path) ||
   98:         is_windows_drive_prefix(path)) {
   99:         return 0;
  100:     }
  101: #endif
  102: 
  103:     return strchr(path, ':') != NULL;
  104: }
  105: 
  106: int path_is_absolute(const char *path)
  107: {
  108:     const char *p;
  109: #ifdef _WIN32
  110:     /* specific case for names like: "\\.\d:" */
  111:     if (*path == '/' || *path == '\\')
  112:         return 1;
  113: #endif
  114:     p = strchr(path, ':');
  115:     if (p)
  116:         p++;
  117:     else
  118:         p = path;
  119: #ifdef _WIN32
  120:     return (*p == '/' || *p == '\\');
  121: #else
  122:     return (*p == '/');
  123: #endif
  124: }
  125: 
  126: /* if filename is absolute, just copy it to dest. Otherwise, build a
  127:    path to it by considering it is relative to base_path. URL are
  128:    supported. */
  129: void path_combine(char *dest, int dest_size,
  130:                   const char *base_path,
  131:                   const char *filename)
  132: {
  133:     const char *p, *p1;
  134:     int len;
  135: 
  136:     if (dest_size <= 0)
  137:         return;
  138:     if (path_is_absolute(filename)) {
  139:         pstrcpy(dest, dest_size, filename);
  140:     } else {
  141:         p = strchr(base_path, ':');
  142:         if (p)
  143:             p++;
  144:         else
  145:             p = base_path;
  146:         p1 = strrchr(base_path, '/');
  147: #ifdef _WIN32
  148:         {
  149:             const char *p2;
  150:             p2 = strrchr(base_path, '\\');
  151:             if (!p1 || p2 > p1)
  152:                 p1 = p2;
  153:         }
  154: #endif
  155:         if (p1)
  156:             p1++;
  157:         else
  158:             p1 = base_path;
  159:         if (p1 > p)
  160:             p = p1;
  161:         len = p - base_path;
  162:         if (len > dest_size - 1)
  163:             len = dest_size - 1;
  164:         memcpy(dest, base_path, len);
  165:         dest[len] = '\0';
  166:         pstrcat(dest, dest_size, filename);
  167:     }
  168: }
  169: 
  170: void bdrv_register(BlockDriver *bdrv)
  171: {
  172:     if (!bdrv->bdrv_aio_readv) {
  173:         /* add AIO emulation layer */
  174:         bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
  175:         bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
  176:     } else if (!bdrv->bdrv_read) {
  177:         /* add synchronous IO emulation layer */
  178:         bdrv->bdrv_read = bdrv_read_em;
  179:         bdrv->bdrv_write = bdrv_write_em;
  180:     }
  181: 
  182:     if (!bdrv->bdrv_aio_flush)
  183:         bdrv->bdrv_aio_flush = bdrv_aio_flush_em;
  184: 
  185:     QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
  186: }
  187: 
  188: /* create a new block device (by default it is empty) */
  189: BlockDriverState *bdrv_new(const char *device_name)
  190: {
  191:     BlockDriverState *bs;
  192: 
  193:     bs = qemu_mallocz(sizeof(BlockDriverState));
  194:     pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
  195:     if (device_name[0] != '\0') {
  196:         QTAILQ_INSERT_TAIL(&bdrv_states, bs, list);
  197:     }
  198:     return bs;
  199: }
  200: 
  201: BlockDriver *bdrv_find_format(const char *format_name)
  202: {
  203:     BlockDriver *drv1;
  204:     QLIST_FOREACH(drv1, &bdrv_drivers, list) {
  205:         if (!strcmp(drv1->format_name, format_name)) {
  206:             return drv1;
  207:         }
  208:     }
  209:     return NULL;
  210: }
  211: 
  212: static int bdrv_is_whitelisted(BlockDriver *drv)
  213: {
  214:     static const char *whitelist[] = {
  215:         CONFIG_BDRV_WHITELIST
  216:     };
  217:     const char **p;
  218: 
  219:     if (!whitelist[0])
  220:         return 1;               /* no whitelist, anything goes */
  221: 
  222:     for (p = whitelist; *p; p++) {
  223:         if (!strcmp(drv->format_name, *p)) {
  224:             return 1;
  225:         }
  226:     }
  227:     return 0;
  228: }
  229: 
  230: BlockDriver *bdrv_find_whitelisted_format(const char *format_name)
  231: {
  232:     BlockDriver *drv = bdrv_find_format(format_name);
  233:     return drv && bdrv_is_whitelisted(drv) ? drv : NULL;
  234: }
  235: 
  236: int bdrv_create(BlockDriver *drv, const char* filename,
  237:     QEMUOptionParameter *options)
  238: {
  239:     if (!drv->bdrv_create)
  240:         return -ENOTSUP;
  241: 
  242:     return drv->bdrv_create(filename, options);
  243: }
  244: 
  245: int bdrv_create_file(const char* filename, QEMUOptionParameter *options)
  246: {
  247:     BlockDriver *drv;
  248: 
  249:     drv = bdrv_find_protocol(filename);
  250:     if (drv == NULL) {
  251:         return -ENOENT;
  252:     }
  253: 
  254:     return bdrv_create(drv, filename, options);
  255: }
  256: 
  257: #ifdef _WIN32
  258: void get_tmp_filename(char *filename, int size)
  259: {
  260:     char temp_dir[MAX_PATH];
  261: 
  262:     GetTempPath(MAX_PATH, temp_dir);
  263:     GetTempFileName(temp_dir, "qem", 0, filename);
  264: }
  265: #else
  266: void get_tmp_filename(char *filename, int size)
  267: {
  268:     int fd;
  269:     const char *tmpdir;
  270:     /* XXX: race condition possible */
  271:     tmpdir = getenv("TMPDIR");
  272:     if (!tmpdir)
  273:         tmpdir = "/tmp";
  274:     snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
  275:     fd = mkstemp(filename);
  276:     close(fd);
  277: }
  278: #endif
  279: 
  280: /*
  281:  * Detect host devices. By convention, /dev/cdrom[N] is always
  282:  * recognized as a host CDROM.
  283:  */
  284: static BlockDriver *find_hdev_driver(const char *filename)
  285: {
  286:     int score_max = 0, score;
  287:     BlockDriver *drv = NULL, *d;
  288: 
  289:     QLIST_FOREACH(d, &bdrv_drivers, list) {
  290:         if (d->bdrv_probe_device) {
  291:             score = d->bdrv_probe_device(filename);
  292:             if (score > score_max) {
  293:                 score_max = score;
  294:                 drv = d;
  295:             }
  296:         }
  297:     }
  298: 
  299:     return drv;
  300: }
  301: 
  302: BlockDriver *bdrv_find_protocol(const char *filename)
  303: {
  304:     BlockDriver *drv1;
  305:     char protocol[128];
  306:     int len;
  307:     const char *p;
  308: 
  309:     /* TODO Drivers without bdrv_file_open must be specified explicitly */
  310: 
  311:     /*
  312:      * XXX(hch): we really should not let host device detection
  313:      * override an explicit protocol specification, but moving this
  314:      * later breaks access to device names with colons in them.
  315:      * Thanks to the brain-dead persistent naming schemes on udev-
  316:      * based Linux systems those actually are quite common.
  317:      */
  318:     drv1 = find_hdev_driver(filename);
  319:     if (drv1) {
  320:         return drv1;
  321:     }
  322: 
  323:     if (!path_has_protocol(filename)) {
  324:         return bdrv_find_format("file");
  325:     }
  326:     p = strchr(filename, ':');
  327:     assert(p != NULL);
  328:     len = p - filename;
  329:     if (len > sizeof(protocol) - 1)
  330:         len = sizeof(protocol) - 1;
  331:     memcpy(protocol, filename, len);
  332:     protocol[len] = '\0';
  333:     QLIST_FOREACH(drv1, &bdrv_drivers, list) {
  334:         if (drv1->protocol_name &&
  335:             !strcmp(drv1->protocol_name, protocol)) {
  336:             return drv1;
  337:         }
  338:     }
  339:     return NULL;
  340: }
  341: 
  342: static int find_image_format(const char *filename, BlockDriver **pdrv)
  343: {
  344:     int ret, score, score_max;
  345:     BlockDriver *drv1, *drv;
  346:     uint8_t buf[2048];
  347:     BlockDriverState *bs;
  348: 
  349:     ret = bdrv_file_open(&bs, filename, 0);
  350:     if (ret < 0) {
  351:         *pdrv = NULL;
  352:         return ret;
  353:     }
  354: 
  355:     /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
  356:     if (bs->sg || !bdrv_is_inserted(bs)) {
  357:         bdrv_delete(bs);
  358:         drv = bdrv_find_format("raw");
  359:         if (!drv) {
  360:             ret = -ENOENT;
  361:         }
  362:         *pdrv = drv;
  363:         return ret;
  364:     }
  365: 
  366:     ret = bdrv_pread(bs, 0, buf, sizeof(buf));
  367:     bdrv_delete(bs);
  368:     if (ret < 0) {
  369:         *pdrv = NULL;
  370:         return ret;
  371:     }
  372: 
  373:     score_max = 0;
  374:     drv = NULL;
  375:     QLIST_FOREACH(drv1, &bdrv_drivers, list) {
  376:         if (drv1->bdrv_probe) {
  377:             score = drv1->bdrv_probe(buf, ret, filename);
  378:             if (score > score_max) {
  379:                 score_max = score;
  380:                 drv = drv1;
  381:             }
  382:         }
  383:     }
  384:     if (!drv) {
  385:         ret = -ENOENT;
  386:     }
  387:     *pdrv = drv;
  388:     return ret;
  389: }
  390: 
  391: /**
  392:  * Set the current 'total_sectors' value
  393:  */
  394: static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
  395: {
  396:     BlockDriver *drv = bs->drv;
  397: 
  398:     /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
  399:     if (bs->sg)
  400:         return 0;
  401: 
  402:     /* query actual device if possible, otherwise just trust the hint */
  403:     if (drv->bdrv_getlength) {
  404:         int64_t length = drv->bdrv_getlength(bs);
  405:         if (length < 0) {
  406:             return length;
  407:         }
  408:         hint = length >> BDRV_SECTOR_BITS;
  409:     }
  410: 
  411:     bs->total_sectors = hint;
  412:     return 0;
  413: }
  414: 
  415: /*
  416:  * Common part for opening disk images and files
  417:  */
  418: static int bdrv_open_common(BlockDriverState *bs, const char *filename,
  419:     int flags, BlockDriver *drv)
  420: {
  421:     int ret, open_flags;
  422: 
  423:     assert(drv != NULL);
  424: 
  425:     bs->file = NULL;
  426:     bs->total_sectors = 0;
  427:     bs->encrypted = 0;
  428:     bs->valid_key = 0;
  429:     bs->open_flags = flags;
  430:     /* buffer_alignment defaulted to 512, drivers can change this value */
  431:     bs->buffer_alignment = 512;
  432: 
  433:     pstrcpy(bs->filename, sizeof(bs->filename), filename);
  434: 
  435:     if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
  436:         return -ENOTSUP;
  437:     }
  438: 
  439:     bs->drv = drv;
  440:     bs->opaque = qemu_mallocz(drv->instance_size);
  441: 
  442:     /*
  443:      * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a
  444:      * write cache to the guest.  We do need the fdatasync to flush
  445:      * out transactions for block allocations, and we maybe have a
  446:      * volatile write cache in our backing device to deal with.
  447:      */
  448:     if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE))
  449:         bs->enable_write_cache = 1;
  450: 
  451:     /*
  452:      * Clear flags that are internal to the block layer before opening the
  453:      * image.
  454:      */
  455:     open_flags = flags & ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
  456: 
  457:     /*
  458:      * Snapshots should be writeable.
  459:      */
  460:     if (bs->is_temporary) {
  461:         open_flags |= BDRV_O_RDWR;
  462:     }
  463: 
  464:     /* Open the image, either directly or using a protocol */
  465:     if (drv->bdrv_file_open) {
  466:         ret = drv->bdrv_file_open(bs, filename, open_flags);
  467:     } else {
  468:         ret = bdrv_file_open(&bs->file, filename, open_flags);
  469:         if (ret >= 0) {
  470:             ret = drv->bdrv_open(bs, open_flags);
  471:         }
  472:     }
  473: 
  474:     if (ret < 0) {
  475:         goto free_and_fail;
  476:     }
  477: 
  478:     bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR);
  479: 
  480:     ret = refresh_total_sectors(bs, bs->total_sectors);
  481:     if (ret < 0) {
  482:         goto free_and_fail;
  483:     }
  484: 
  485: #ifndef _WIN32
  486:     if (bs->is_temporary) {
  487:         unlink(filename);
  488:     }
  489: #endif
  490:     return 0;
  491: 
  492: free_and_fail:
  493:     if (bs->file) {
  494:         bdrv_delete(bs->file);
  495:         bs->file = NULL;
  496:     }
  497:     qemu_free(bs->opaque);
  498:     bs->opaque = NULL;
  499:     bs->drv = NULL;
  500:     return ret;
  501: }
  502: 
  503: /*
  504:  * Opens a file using a protocol (file, host_device, nbd, ...)
  505:  */
  506: int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
  507: {
  508:     BlockDriverState *bs;
  509:     BlockDriver *drv;
  510:     int ret;
  511: 
  512:     drv = bdrv_find_protocol(filename);
  513:     if (!drv) {
  514:         return -ENOENT;
  515:     }
  516: 
  517:     bs = bdrv_new("");
  518:     ret = bdrv_open_common(bs, filename, flags, drv);
  519:     if (ret < 0) {
  520:         bdrv_delete(bs);
  521:         return ret;
  522:     }
  523:     bs->growable = 1;
  524:     *pbs = bs;
  525:     return 0;
  526: }
  527: 
  528: /*
  529:  * Opens a disk image (raw, qcow2, vmdk, ...)
  530:  */
  531: int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
  532:               BlockDriver *drv)
  533: {
  534:     int ret;
  535: 
  536:     if (flags & BDRV_O_SNAPSHOT) {
  537:         BlockDriverState *bs1;
  538:         int64_t total_size;
  539:         int is_protocol = 0;
  540:         BlockDriver *bdrv_qcow2;
  541:         QEMUOptionParameter *options;
  542:         char tmp_filename[PATH_MAX];
  543:         char backing_filename[PATH_MAX];
  544: 
  545:         /* if snapshot, we create a temporary backing file and open it
  546:            instead of opening 'filename' directly */
  547: 
  548:         /* if there is a backing file, use it */
  549:         bs1 = bdrv_new("");
  550:         ret = bdrv_open(bs1, filename, 0, drv);
  551:         if (ret < 0) {
  552:             bdrv_delete(bs1);
  553:             return ret;
  554:         }
  555:         total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK;
  556: 
  557:         if (bs1->drv && bs1->drv->protocol_name)
  558:             is_protocol = 1;
  559: 
  560:         bdrv_delete(bs1);
  561: 
  562:         get_tmp_filename(tmp_filename, sizeof(tmp_filename));
  563: 
  564:         /* Real path is meaningless for protocols */
  565:         if (is_protocol)
  566:             snprintf(backing_filename, sizeof(backing_filename),
  567:                      "%s", filename);
  568:         else if (!realpath(filename, backing_filename))
  569:             return -errno;
  570: 
  571:         bdrv_qcow2 = bdrv_find_format("qcow2");
  572:         options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
  573: 
  574:         set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size);
  575:         set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
  576:         if (drv) {
  577:             set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
  578:                 drv->format_name);
  579:         }
  580: 
  581:         ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
  582:         free_option_parameters(options);
  583:         if (ret < 0) {
  584:             return ret;
  585:         }
  586: 
  587:         filename = tmp_filename;
  588:         drv = bdrv_qcow2;
  589:         bs->is_temporary = 1;
  590:     }
  591: 
  592:     /* Find the right image format driver */
  593:     if (!drv) {
  594:         ret = find_image_format(filename, &drv);
  595:     }
  596: 
  597:     if (!drv) {
  598:         goto unlink_and_fail;
  599:     }
  600: 
  601:     /* Open the image */
  602:     ret = bdrv_open_common(bs, filename, flags, drv);
  603:     if (ret < 0) {
  604:         goto unlink_and_fail;
  605:     }
  606: 
  607:     /* If there is a backing file, use it */
  608:     if ((flags & BDRV_O_NO_BACKING) == 0 && bs->backing_file[0] != '\0') {
  609:         char backing_filename[PATH_MAX];
  610:         int back_flags;
  611:         BlockDriver *back_drv = NULL;
  612: 
  613:         bs->backing_hd = bdrv_new("");
  614: 
  615:         if (path_has_protocol(bs->backing_file)) {
  616:             pstrcpy(backing_filename, sizeof(backing_filename),
  617:                     bs->backing_file);
  618:         } else {
  619:             path_combine(backing_filename, sizeof(backing_filename),
  620:                          filename, bs->backing_file);
  621:         }
  622: 
  623:         if (bs->backing_format[0] != '\0') {
  624:             back_drv = bdrv_find_format(bs->backing_format);
  625:         }
  626: 
  627:         /* backing files always opened read-only */
  628:         back_flags =
  629:             flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
  630: 
  631:         ret = bdrv_open(bs->backing_hd, backing_filename, back_flags, back_drv);
  632:         if (ret < 0) {
  633:             bdrv_close(bs);
  634:             return ret;
  635:         }
  636:         if (bs->is_temporary) {
  637:             bs->backing_hd->keep_read_only = !(flags & BDRV_O_RDWR);
  638:         } else {
  639:             /* base image inherits from "parent" */
  640:             bs->backing_hd->keep_read_only = bs->keep_read_only;
  641:         }
  642:     }
  643: 
  644:     if (!bdrv_key_required(bs)) {
  645:         /* call the change callback */
  646:         bs->media_changed = 1;
  647:         if (bs->change_cb)
  648:             bs->change_cb(bs->change_opaque, CHANGE_MEDIA);
  649:     }
  650: 
  651:     return 0;
  652: 
  653: unlink_and_fail:
  654:     if (bs->is_temporary) {
  655:         unlink(filename);
  656:     }
  657:     return ret;
  658: }
  659: 
  660: void bdrv_close(BlockDriverState *bs)
  661: {
  662:     if (bs->drv) {
  663:         if (bs == bs_snapshots) {
  664:             bs_snapshots = NULL;
  665:         }
  666:         if (bs->backing_hd) {
  667:             bdrv_delete(bs->backing_hd);
  668:             bs->backing_hd = NULL;
  669:         }
  670:         bs->drv->bdrv_close(bs);
  671:         qemu_free(bs->opaque);
  672: #ifdef _WIN32
  673:         if (bs->is_temporary) {
  674:             unlink(bs->filename);
  675:         }
  676: #endif
  677:         bs->opaque = NULL;
  678:         bs->drv = NULL;
  679: 
  680:         if (bs->file != NULL) {
  681:             bdrv_close(bs->file);
  682:         }
  683: 
  684:         /* call the change callback */
  685:         bs->media_changed = 1;
  686:         if (bs->change_cb)
  687:             bs->change_cb(bs->change_opaque, CHANGE_MEDIA);
  688:     }
  689: }
  690: 
  691: void bdrv_close_all(void)
  692: {
  693:     BlockDriverState *bs;
  694: 
  695:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
  696:         bdrv_close(bs);
  697:     }
  698: }
  699: 
  700: void bdrv_delete(BlockDriverState *bs)
  701: {
  702:     assert(!bs->peer);
  703: 
  704:     /* remove from list, if necessary */
  705:     if (bs->device_name[0] != '\0') {
  706:         QTAILQ_REMOVE(&bdrv_states, bs, list);
  707:     }
  708: 
  709:     bdrv_close(bs);
  710:     if (bs->file != NULL) {
  711:         bdrv_delete(bs->file);
  712:     }
  713: 
  714:     assert(bs != bs_snapshots);
  715:     qemu_free(bs);
  716: }
  717: 
  718: int bdrv_attach(BlockDriverState *bs, DeviceState *qdev)
  719: {
  720:     if (bs->peer) {
  721:         return -EBUSY;
  722:     }
  723:     bs->peer = qdev;
  724:     return 0;
  725: }
  726: 
  727: void bdrv_detach(BlockDriverState *bs, DeviceState *qdev)
  728: {
  729:     assert(bs->peer == qdev);
  730:     bs->peer = NULL;
  731: }
  732: 
  733: DeviceState *bdrv_get_attached(BlockDriverState *bs)
  734: {
  735:     return bs->peer;
  736: }
  737: 
  738: /*
  739:  * Run consistency checks on an image
  740:  *
  741:  * Returns 0 if the check could be completed (it doesn't mean that the image is
  742:  * free of errors) or -errno when an internal error occured. The results of the
  743:  * check are stored in res.
  744:  */
  745: int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res)
  746: {
  747:     if (bs->drv->bdrv_check == NULL) {
  748:         return -ENOTSUP;
  749:     }
  750: 
  751:     memset(res, 0, sizeof(*res));
  752:     return bs->drv->bdrv_check(bs, res);
  753: }
  754: 
  755: #define COMMIT_BUF_SECTORS 2048
  756: 
  757: /* commit COW file into the raw image */
  758: int bdrv_commit(BlockDriverState *bs)
  759: {
  760:     BlockDriver *drv = bs->drv;
  761:     BlockDriver *backing_drv;
  762:     int64_t sector, total_sectors;
  763:     int n, ro, open_flags;
  764:     int ret = 0, rw_ret = 0;
  765:     uint8_t *buf;
  766:     char filename[1024];
  767:     BlockDriverState *bs_rw, *bs_ro;
  768: 
  769:     if (!drv)
  770:         return -ENOMEDIUM;
  771:     
  772:     if (!bs->backing_hd) {
  773:         return -ENOTSUP;
  774:     }
  775: 
  776:     if (bs->backing_hd->keep_read_only) {
  777:         return -EACCES;
  778:     }
  779: 
  780:     backing_drv = bs->backing_hd->drv;
  781:     ro = bs->backing_hd->read_only;
  782:     strncpy(filename, bs->backing_hd->filename, sizeof(filename));
  783:     open_flags =  bs->backing_hd->open_flags;
  784: 
  785:     if (ro) {
  786:         /* re-open as RW */
  787:         bdrv_delete(bs->backing_hd);
  788:         bs->backing_hd = NULL;
  789:         bs_rw = bdrv_new("");
  790:         rw_ret = bdrv_open(bs_rw, filename, open_flags | BDRV_O_RDWR,
  791:             backing_drv);
  792:         if (rw_ret < 0) {
  793:             bdrv_delete(bs_rw);
  794:             /* try to re-open read-only */
  795:             bs_ro = bdrv_new("");
  796:             ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR,
  797:                 backing_drv);
  798:             if (ret < 0) {
  799:                 bdrv_delete(bs_ro);
  800:                 /* drive not functional anymore */
  801:                 bs->drv = NULL;
  802:                 return ret;
  803:             }
  804:             bs->backing_hd = bs_ro;
  805:             return rw_ret;
  806:         }
  807:         bs->backing_hd = bs_rw;
  808:     }
  809: 
  810:     total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
  811:     buf = qemu_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE);
  812: 
  813:     for (sector = 0; sector < total_sectors; sector += n) {
  814:         if (drv->bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n)) {
  815: 
  816:             if (bdrv_read(bs, sector, buf, n) != 0) {
  817:                 ret = -EIO;
  818:                 goto ro_cleanup;
  819:             }
  820: 
  821:             if (bdrv_write(bs->backing_hd, sector, buf, n) != 0) {
  822:                 ret = -EIO;
  823:                 goto ro_cleanup;
  824:             }
  825:         }
  826:     }
  827: 
  828:     if (drv->bdrv_make_empty) {
  829:         ret = drv->bdrv_make_empty(bs);
  830:         bdrv_flush(bs);
  831:     }
  832: 
  833:     /*
  834:      * Make sure all data we wrote to the backing device is actually
  835:      * stable on disk.
  836:      */
  837:     if (bs->backing_hd)
  838:         bdrv_flush(bs->backing_hd);
  839: 
  840: ro_cleanup:
  841:     qemu_free(buf);
  842: 
  843:     if (ro) {
  844:         /* re-open as RO */
  845:         bdrv_delete(bs->backing_hd);
  846:         bs->backing_hd = NULL;
  847:         bs_ro = bdrv_new("");
  848:         ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR,
  849:             backing_drv);
  850:         if (ret < 0) {
  851:             bdrv_delete(bs_ro);
  852:             /* drive not functional anymore */
  853:             bs->drv = NULL;
  854:             return ret;
  855:         }
  856:         bs->backing_hd = bs_ro;
  857:         bs->backing_hd->keep_read_only = 0;
  858:     }
  859: 
  860:     return ret;
  861: }
  862: 
  863: void bdrv_commit_all(void)
  864: {
  865:     BlockDriverState *bs;
  866: 
  867:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
  868:         bdrv_commit(bs);
  869:     }
  870: }
  871: 
  872: /*
  873:  * Return values:
  874:  * 0        - success
  875:  * -EINVAL  - backing format specified, but no file
  876:  * -ENOSPC  - can't update the backing file because no space is left in the
  877:  *            image file header
  878:  * -ENOTSUP - format driver doesn't support changing the backing file
  879:  */
  880: int bdrv_change_backing_file(BlockDriverState *bs,
  881:     const char *backing_file, const char *backing_fmt)
  882: {
  883:     BlockDriver *drv = bs->drv;
  884: 
  885:     if (drv->bdrv_change_backing_file != NULL) {
  886:         return drv->bdrv_change_backing_file(bs, backing_file, backing_fmt);
  887:     } else {
  888:         return -ENOTSUP;
  889:     }
  890: }
  891: 
  892: static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
  893:                                    size_t size)
  894: {
  895:     int64_t len;
  896: 
  897:     if (!bdrv_is_inserted(bs))
  898:         return -ENOMEDIUM;
  899: 
  900:     if (bs->growable)
  901:         return 0;
  902: 
  903:     len = bdrv_getlength(bs);
  904: 
  905:     if (offset < 0)
  906:         return -EIO;
  907: 
  908:     if ((offset > len) || (len - offset < size))
  909:         return -EIO;
  910: 
  911:     return 0;
  912: }
  913: 
  914: static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
  915:                               int nb_sectors)
  916: {
  917:     return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
  918:                                    nb_sectors * BDRV_SECTOR_SIZE);
  919: }
  920: 
  921: /* return < 0 if error. See bdrv_write() for the return codes */
  922: int bdrv_read(BlockDriverState *bs, int64_t sector_num,
  923:               uint8_t *buf, int nb_sectors)
  924: {
  925:     BlockDriver *drv = bs->drv;
  926: 
  927:     if (!drv)
  928:         return -ENOMEDIUM;
  929:     if (bdrv_check_request(bs, sector_num, nb_sectors))
  930:         return -EIO;
  931: 
  932:     return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
  933: }
  934: 
  935: static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num,
  936:                              int nb_sectors, int dirty)
  937: {
  938:     int64_t start, end;
  939:     unsigned long val, idx, bit;
  940: 
  941:     start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
  942:     end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
  943: 
  944:     for (; start <= end; start++) {
  945:         idx = start / (sizeof(unsigned long) * 8);
  946:         bit = start % (sizeof(unsigned long) * 8);
  947:         val = bs->dirty_bitmap[idx];
  948:         if (dirty) {
  949:             if (!(val & (1UL << bit))) {
  950:                 bs->dirty_count++;
  951:                 val |= 1UL << bit;
  952:             }
  953:         } else {
  954:             if (val & (1UL << bit)) {
  955:                 bs->dirty_count--;
  956:                 val &= ~(1UL << bit);
  957:             }
  958:         }
  959:         bs->dirty_bitmap[idx] = val;
  960:     }
  961: }
  962: 
  963: /* Return < 0 if error. Important errors are:
  964:   -EIO         generic I/O error (may happen for all errors)
  965:   -ENOMEDIUM   No media inserted.
  966:   -EINVAL      Invalid sector number or nb_sectors
  967:   -EACCES      Trying to write a read-only device
  968: */
  969: int bdrv_write(BlockDriverState *bs, int64_t sector_num,
  970:                const uint8_t *buf, int nb_sectors)
  971: {
  972:     BlockDriver *drv = bs->drv;
  973:     if (!bs->drv)
  974:         return -ENOMEDIUM;
  975:     if (bs->read_only)
  976:         return -EACCES;
  977:     if (bdrv_check_request(bs, sector_num, nb_sectors))
  978:         return -EIO;
  979: 
  980:     if (bs->dirty_bitmap) {
  981:         set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
  982:     }
  983: 
  984:     if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
  985:         bs->wr_highest_sector = sector_num + nb_sectors - 1;
  986:     }
  987: 
  988:     return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
  989: }
  990: 
  991: int bdrv_pread(BlockDriverState *bs, int64_t offset,
  992:                void *buf, int count1)
  993: {
  994:     uint8_t tmp_buf[BDRV_SECTOR_SIZE];
  995:     int len, nb_sectors, count;
  996:     int64_t sector_num;
  997:     int ret;
  998: 
  999:     count = count1;
 1000:     /* first read to align to sector start */
 1001:     len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
 1002:     if (len > count)
 1003:         len = count;
 1004:     sector_num = offset >> BDRV_SECTOR_BITS;
 1005:     if (len > 0) {
 1006:         if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
 1007:             return ret;
 1008:         memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len);
 1009:         count -= len;
 1010:         if (count == 0)
 1011:             return count1;
 1012:         sector_num++;
 1013:         buf += len;
 1014:     }
 1015: 
 1016:     /* read the sectors "in place" */
 1017:     nb_sectors = count >> BDRV_SECTOR_BITS;
 1018:     if (nb_sectors > 0) {
 1019:         if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0)
 1020:             return ret;
 1021:         sector_num += nb_sectors;
 1022:         len = nb_sectors << BDRV_SECTOR_BITS;
 1023:         buf += len;
 1024:         count -= len;
 1025:     }
 1026: 
 1027:     /* add data from the last sector */
 1028:     if (count > 0) {
 1029:         if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
 1030:             return ret;
 1031:         memcpy(buf, tmp_buf, count);
 1032:     }
 1033:     return count1;
 1034: }
 1035: 
 1036: int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
 1037:                 const void *buf, int count1)
 1038: {
 1039:     uint8_t tmp_buf[BDRV_SECTOR_SIZE];
 1040:     int len, nb_sectors, count;
 1041:     int64_t sector_num;
 1042:     int ret;
 1043: 
 1044:     count = count1;
 1045:     /* first write to align to sector start */
 1046:     len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
 1047:     if (len > count)
 1048:         len = count;
 1049:     sector_num = offset >> BDRV_SECTOR_BITS;
 1050:     if (len > 0) {
 1051:         if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
 1052:             return ret;
 1053:         memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len);
 1054:         if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
 1055:             return ret;
 1056:         count -= len;
 1057:         if (count == 0)
 1058:             return count1;
 1059:         sector_num++;
 1060:         buf += len;
 1061:     }
 1062: 
 1063:     /* write the sectors "in place" */
 1064:     nb_sectors = count >> BDRV_SECTOR_BITS;
 1065:     if (nb_sectors > 0) {
 1066:         if ((ret = bdrv_write(bs, sector_num, buf, nb_sectors)) < 0)
 1067:             return ret;
 1068:         sector_num += nb_sectors;
 1069:         len = nb_sectors << BDRV_SECTOR_BITS;
 1070:         buf += len;
 1071:         count -= len;
 1072:     }
 1073: 
 1074:     /* add data from the last sector */
 1075:     if (count > 0) {
 1076:         if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
 1077:             return ret;
 1078:         memcpy(tmp_buf, buf, count);
 1079:         if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
 1080:             return ret;
 1081:     }
 1082:     return count1;
 1083: }
 1084: 
 1085: /*
 1086:  * Writes to the file and ensures that no writes are reordered across this
 1087:  * request (acts as a barrier)
 1088:  *
 1089:  * Returns 0 on success, -errno in error cases.
 1090:  */
 1091: int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
 1092:     const void *buf, int count)
 1093: {
 1094:     int ret;
 1095: 
 1096:     ret = bdrv_pwrite(bs, offset, buf, count);
 1097:     if (ret < 0) {
 1098:         return ret;
 1099:     }
 1100: 
 1101:     /* No flush needed for cache=writethrough, it uses O_DSYNC */
 1102:     if ((bs->open_flags & BDRV_O_CACHE_MASK) != 0) {
 1103:         bdrv_flush(bs);
 1104:     }
 1105: 
 1106:     return 0;
 1107: }
 1108: 
 1109: /*
 1110:  * Writes to the file and ensures that no writes are reordered across this
 1111:  * request (acts as a barrier)
 1112:  *
 1113:  * Returns 0 on success, -errno in error cases.
 1114:  */
 1115: int bdrv_write_sync(BlockDriverState *bs, int64_t sector_num,
 1116:     const uint8_t *buf, int nb_sectors)
 1117: {
 1118:     return bdrv_pwrite_sync(bs, BDRV_SECTOR_SIZE * sector_num,
 1119:         buf, BDRV_SECTOR_SIZE * nb_sectors);
 1120: }
 1121: 
 1122: /**
 1123:  * Truncate file to 'offset' bytes (needed only for file protocols)
 1124:  */
 1125: int bdrv_truncate(BlockDriverState *bs, int64_t offset)
 1126: {
 1127:     BlockDriver *drv = bs->drv;
 1128:     int ret;
 1129:     if (!drv)
 1130:         return -ENOMEDIUM;
 1131:     if (!drv->bdrv_truncate)
 1132:         return -ENOTSUP;
 1133:     if (bs->read_only)
 1134:         return -EACCES;
 1135:     if (bdrv_in_use(bs))
 1136:         return -EBUSY;
 1137:     ret = drv->bdrv_truncate(bs, offset);
 1138:     if (ret == 0) {
 1139:         ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
 1140:         if (bs->change_cb) {
 1141:             bs->change_cb(bs->change_opaque, CHANGE_SIZE);
 1142:         }
 1143:     }
 1144:     return ret;
 1145: }
 1146: 
 1147: /**
 1148:  * Length of a file in bytes. Return < 0 if error or unknown.
 1149:  */
 1150: int64_t bdrv_getlength(BlockDriverState *bs)
 1151: {
 1152:     BlockDriver *drv = bs->drv;
 1153:     if (!drv)
 1154:         return -ENOMEDIUM;
 1155: 
 1156:     /* Fixed size devices use the total_sectors value for speed instead of
 1157:        issuing a length query (like lseek) on each call.  Also, legacy block
 1158:        drivers don't provide a bdrv_getlength function and must use
 1159:        total_sectors. */
 1160:     if (!bs->growable || !drv->bdrv_getlength) {
 1161:         return bs->total_sectors * BDRV_SECTOR_SIZE;
 1162:     }
 1163:     return drv->bdrv_getlength(bs);
 1164: }
 1165: 
 1166: /* return 0 as number of sectors if no device present or error */
 1167: void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
 1168: {
 1169:     int64_t length;
 1170:     length = bdrv_getlength(bs);
 1171:     if (length < 0)
 1172:         length = 0;
 1173:     else
 1174:         length = length >> BDRV_SECTOR_BITS;
 1175:     *nb_sectors_ptr = length;
 1176: }
 1177: 
 1178: struct partition {
 1179:         uint8_t boot_ind;           /* 0x80 - active */
 1180:         uint8_t head;               /* starting head */
 1181:         uint8_t sector;             /* starting sector */
 1182:         uint8_t cyl;                /* starting cylinder */
 1183:         uint8_t sys_ind;            /* What partition type */
 1184:         uint8_t end_head;           /* end head */
 1185:         uint8_t end_sector;         /* end sector */
 1186:         uint8_t end_cyl;            /* end cylinder */
 1187:         uint32_t start_sect;        /* starting sector counting from 0 */
 1188:         uint32_t nr_sects;          /* nr of sectors in partition */
 1189: } __attribute__((packed));
 1190: 
 1191: /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
 1192: static int guess_disk_lchs(BlockDriverState *bs,
 1193:                            int *pcylinders, int *pheads, int *psectors)
 1194: {
 1195:     uint8_t buf[BDRV_SECTOR_SIZE];
 1196:     int ret, i, heads, sectors, cylinders;
 1197:     struct partition *p;
 1198:     uint32_t nr_sects;
 1199:     uint64_t nb_sectors;
 1200: 
 1201:     bdrv_get_geometry(bs, &nb_sectors);
 1202: 
 1203:     ret = bdrv_read(bs, 0, buf, 1);
 1204:     if (ret < 0)
 1205:         return -1;
 1206:     /* test msdos magic */
 1207:     if (buf[510] != 0x55 || buf[511] != 0xaa)
 1208:         return -1;
 1209:     for(i = 0; i < 4; i++) {
 1210:         p = ((struct partition *)(buf + 0x1be)) + i;
 1211:         nr_sects = le32_to_cpu(p->nr_sects);
 1212:         if (nr_sects && p->end_head) {
 1213:             /* We make the assumption that the partition terminates on
 1214:                a cylinder boundary */
 1215:             heads = p->end_head + 1;
 1216:             sectors = p->end_sector & 63;
 1217:             if (sectors == 0)
 1218:                 continue;
 1219:             cylinders = nb_sectors / (heads * sectors);
 1220:             if (cylinders < 1 || cylinders > 16383)
 1221:                 continue;
 1222:             *pheads = heads;
 1223:             *psectors = sectors;
 1224:             *pcylinders = cylinders;
 1225: #if 0
 1226:             printf("guessed geometry: LCHS=%d %d %d\n",
 1227:                    cylinders, heads, sectors);
 1228: #endif
 1229:             return 0;
 1230:         }
 1231:     }
 1232:     return -1;
 1233: }
 1234: 
 1235: void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
 1236: {
 1237:     int translation, lba_detected = 0;
 1238:     int cylinders, heads, secs;
 1239:     uint64_t nb_sectors;
 1240: 
 1241:     /* if a geometry hint is available, use it */
 1242:     bdrv_get_geometry(bs, &nb_sectors);
 1243:     bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
 1244:     translation = bdrv_get_translation_hint(bs);
 1245:     if (cylinders != 0) {
 1246:         *pcyls = cylinders;
 1247:         *pheads = heads;
 1248:         *psecs = secs;
 1249:     } else {
 1250:         if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
 1251:             if (heads > 16) {
 1252:                 /* if heads > 16, it means that a BIOS LBA
 1253:                    translation was active, so the default
 1254:                    hardware geometry is OK */
 1255:                 lba_detected = 1;
 1256:                 goto default_geometry;
 1257:             } else {
 1258:                 *pcyls = cylinders;
 1259:                 *pheads = heads;
 1260:                 *psecs = secs;
 1261:                 /* disable any translation to be in sync with
 1262:                    the logical geometry */
 1263:                 if (translation == BIOS_ATA_TRANSLATION_AUTO) {
 1264:                     bdrv_set_translation_hint(bs,
 1265:                                               BIOS_ATA_TRANSLATION_NONE);
 1266:                 }
 1267:             }
 1268:         } else {
 1269:         default_geometry:
 1270:             /* if no geometry, use a standard physical disk geometry */
 1271:             cylinders = nb_sectors / (16 * 63);
 1272: 
 1273:             if (cylinders > 16383)
 1274:                 cylinders = 16383;
 1275:             else if (cylinders < 2)
 1276:                 cylinders = 2;
 1277:             *pcyls = cylinders;
 1278:             *pheads = 16;
 1279:             *psecs = 63;
 1280:             if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
 1281:                 if ((*pcyls * *pheads) <= 131072) {
 1282:                     bdrv_set_translation_hint(bs,
 1283:                                               BIOS_ATA_TRANSLATION_LARGE);
 1284:                 } else {
 1285:                     bdrv_set_translation_hint(bs,
 1286:                                               BIOS_ATA_TRANSLATION_LBA);
 1287:                 }
 1288:             }
 1289:         }
 1290:         bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
 1291:     }
 1292: }
 1293: 
 1294: void bdrv_set_geometry_hint(BlockDriverState *bs,
 1295:                             int cyls, int heads, int secs)
 1296: {
 1297:     bs->cyls = cyls;
 1298:     bs->heads = heads;
 1299:     bs->secs = secs;
 1300: }
 1301: 
 1302: void bdrv_set_type_hint(BlockDriverState *bs, int type)
 1303: {
 1304:     bs->type = type;
 1305:     bs->removable = ((type == BDRV_TYPE_CDROM ||
 1306:                       type == BDRV_TYPE_FLOPPY));
 1307: }
 1308: 
 1309: void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
 1310: {
 1311:     bs->translation = translation;
 1312: }
 1313: 
 1314: void bdrv_get_geometry_hint(BlockDriverState *bs,
 1315:                             int *pcyls, int *pheads, int *psecs)
 1316: {
 1317:     *pcyls = bs->cyls;
 1318:     *pheads = bs->heads;
 1319:     *psecs = bs->secs;
 1320: }
 1321: 
 1322: int bdrv_get_type_hint(BlockDriverState *bs)
 1323: {
 1324:     return bs->type;
 1325: }
 1326: 
 1327: int bdrv_get_translation_hint(BlockDriverState *bs)
 1328: {
 1329:     return bs->translation;
 1330: }
 1331: 
 1332: void bdrv_set_on_error(BlockDriverState *bs, BlockErrorAction on_read_error,
 1333:                        BlockErrorAction on_write_error)
 1334: {
 1335:     bs->on_read_error = on_read_error;
 1336:     bs->on_write_error = on_write_error;
 1337: }
 1338: 
 1339: BlockErrorAction bdrv_get_on_error(BlockDriverState *bs, int is_read)
 1340: {
 1341:     return is_read ? bs->on_read_error : bs->on_write_error;
 1342: }
 1343: 
 1344: void bdrv_set_removable(BlockDriverState *bs, int removable)
 1345: {
 1346:     bs->removable = removable;
 1347:     if (removable && bs == bs_snapshots) {
 1348:         bs_snapshots = NULL;
 1349:     }
 1350: }
 1351: 
 1352: int bdrv_is_removable(BlockDriverState *bs)
 1353: {
 1354:     return bs->removable;
 1355: }
 1356: 
 1357: int bdrv_is_read_only(BlockDriverState *bs)
 1358: {
 1359:     return bs->read_only;
 1360: }
 1361: 
 1362: int bdrv_is_sg(BlockDriverState *bs)
 1363: {
 1364:     return bs->sg;
 1365: }
 1366: 
 1367: int bdrv_enable_write_cache(BlockDriverState *bs)
 1368: {
 1369:     return bs->enable_write_cache;
 1370: }
 1371: 
 1372: /* XXX: no longer used */
 1373: void bdrv_set_change_cb(BlockDriverState *bs,
 1374:                         void (*change_cb)(void *opaque, int reason),
 1375:                         void *opaque)
 1376: {
 1377:     bs->change_cb = change_cb;
 1378:     bs->change_opaque = opaque;
 1379: }
 1380: 
 1381: int bdrv_is_encrypted(BlockDriverState *bs)
 1382: {
 1383:     if (bs->backing_hd && bs->backing_hd->encrypted)
 1384:         return 1;
 1385:     return bs->encrypted;
 1386: }
 1387: 
 1388: int bdrv_key_required(BlockDriverState *bs)
 1389: {
 1390:     BlockDriverState *backing_hd = bs->backing_hd;
 1391: 
 1392:     if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
 1393:         return 1;
 1394:     return (bs->encrypted && !bs->valid_key);
 1395: }
 1396: 
 1397: int bdrv_set_key(BlockDriverState *bs, const char *key)
 1398: {
 1399:     int ret;
 1400:     if (bs->backing_hd && bs->backing_hd->encrypted) {
 1401:         ret = bdrv_set_key(bs->backing_hd, key);
 1402:         if (ret < 0)
 1403:             return ret;
 1404:         if (!bs->encrypted)
 1405:             return 0;
 1406:     }
 1407:     if (!bs->encrypted) {
 1408:         return -EINVAL;
 1409:     } else if (!bs->drv || !bs->drv->bdrv_set_key) {
 1410:         return -ENOMEDIUM;
 1411:     }
 1412:     ret = bs->drv->bdrv_set_key(bs, key);
 1413:     if (ret < 0) {
 1414:         bs->valid_key = 0;
 1415:     } else if (!bs->valid_key) {
 1416:         bs->valid_key = 1;
 1417:         /* call the change callback now, we skipped it on open */
 1418:         bs->media_changed = 1;
 1419:         if (bs->change_cb)
 1420:             bs->change_cb(bs->change_opaque, CHANGE_MEDIA);
 1421:     }
 1422:     return ret;
 1423: }
 1424: 
 1425: void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
 1426: {
 1427:     if (!bs->drv) {
 1428:         buf[0] = '\0';
 1429:     } else {
 1430:         pstrcpy(buf, buf_size, bs->drv->format_name);
 1431:     }
 1432: }
 1433: 
 1434: void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 1435:                          void *opaque)
 1436: {
 1437:     BlockDriver *drv;
 1438: 
 1439:     QLIST_FOREACH(drv, &bdrv_drivers, list) {
 1440:         it(opaque, drv->format_name);
 1441:     }
 1442: }
 1443: 
 1444: BlockDriverState *bdrv_find(const char *name)
 1445: {
 1446:     BlockDriverState *bs;
 1447: 
 1448:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
 1449:         if (!strcmp(name, bs->device_name)) {
 1450:             return bs;
 1451:         }
 1452:     }
 1453:     return NULL;
 1454: }
 1455: 
 1456: BlockDriverState *bdrv_next(BlockDriverState *bs)
 1457: {
 1458:     if (!bs) {
 1459:         return QTAILQ_FIRST(&bdrv_states);
 1460:     }
 1461:     return QTAILQ_NEXT(bs, list);
 1462: }
 1463: 
 1464: void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
 1465: {
 1466:     BlockDriverState *bs;
 1467: 
 1468:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
 1469:         it(opaque, bs);
 1470:     }
 1471: }
 1472: 
 1473: const char *bdrv_get_device_name(BlockDriverState *bs)
 1474: {
 1475:     return bs->device_name;
 1476: }
 1477: 
 1478: int bdrv_flush(BlockDriverState *bs)
 1479: {
 1480:     if (bs->open_flags & BDRV_O_NO_FLUSH) {
 1481:         return 0;
 1482:     }
 1483: 
 1484:     if (bs->drv && bs->drv->bdrv_flush) {
 1485:         return bs->drv->bdrv_flush(bs);
 1486:     }
 1487: 
 1488:     /*
 1489:      * Some block drivers always operate in either writethrough or unsafe mode
 1490:      * and don't support bdrv_flush therefore. Usually qemu doesn't know how
 1491:      * the server works (because the behaviour is hardcoded or depends on
 1492:      * server-side configuration), so we can't ensure that everything is safe
 1493:      * on disk. Returning an error doesn't work because that would break guests
 1494:      * even if the server operates in writethrough mode.
 1495:      *
 1496:      * Let's hope the user knows what he's doing.
 1497:      */
 1498:     return 0;
 1499: }
 1500: 
 1501: void bdrv_flush_all(void)
 1502: {
 1503:     BlockDriverState *bs;
 1504: 
 1505:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
 1506:         if (bs->drv && !bdrv_is_read_only(bs) &&
 1507:             (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) {
 1508:             bdrv_flush(bs);
 1509:         }
 1510:     }
 1511: }
 1512: 
 1513: int bdrv_has_zero_init(BlockDriverState *bs)
 1514: {
 1515:     assert(bs->drv);
 1516: 
 1517:     if (bs->drv->bdrv_has_zero_init) {
 1518:         return bs->drv->bdrv_has_zero_init(bs);
 1519:     }
 1520: 
 1521:     return 1;
 1522: }
 1523: 
 1524: int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
 1525: {
 1526:     if (!bs->drv) {
 1527:         return -ENOMEDIUM;
 1528:     }
 1529:     if (!bs->drv->bdrv_discard) {
 1530:         return 0;
 1531:     }
 1532:     return bs->drv->bdrv_discard(bs, sector_num, nb_sectors);
 1533: }
 1534: 
 1535: /*
 1536:  * Returns true iff the specified sector is present in the disk image. Drivers
 1537:  * not implementing the functionality are assumed to not support backing files,
 1538:  * hence all their sectors are reported as allocated.
 1539:  *
 1540:  * 'pnum' is set to the number of sectors (including and immediately following
 1541:  * the specified sector) that are known to be in the same
 1542:  * allocated/unallocated state.
 1543:  *
 1544:  * 'nb_sectors' is the max value 'pnum' should be set to.
 1545:  */
 1546: int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 1547: 	int *pnum)
 1548: {
 1549:     int64_t n;
 1550:     if (!bs->drv->bdrv_is_allocated) {
 1551:         if (sector_num >= bs->total_sectors) {
 1552:             *pnum = 0;
 1553:             return 0;
 1554:         }
 1555:         n = bs->total_sectors - sector_num;
 1556:         *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
 1557:         return 1;
 1558:     }
 1559:     return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
 1560: }
 1561: 
 1562: void bdrv_mon_event(const BlockDriverState *bdrv,
 1563:                     BlockMonEventAction action, int is_read)
 1564: {
 1565:     QObject *data;
 1566:     const char *action_str;
 1567: 
 1568:     switch (action) {
 1569:     case BDRV_ACTION_REPORT:
 1570:         action_str = "report";
 1571:         break;
 1572:     case BDRV_ACTION_IGNORE:
 1573:         action_str = "ignore";
 1574:         break;
 1575:     case BDRV_ACTION_STOP:
 1576:         action_str = "stop";
 1577:         break;
 1578:     default:
 1579:         abort();
 1580:     }
 1581: 
 1582:     data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
 1583:                               bdrv->device_name,
 1584:                               action_str,
 1585:                               is_read ? "read" : "write");
 1586:     monitor_protocol_event(QEVENT_BLOCK_IO_ERROR, data);
 1587: 
 1588:     qobject_decref(data);
 1589: }
 1590: 
 1591: static void bdrv_print_dict(QObject *obj, void *opaque)
 1592: {
 1593:     QDict *bs_dict;
 1594:     Monitor *mon = opaque;
 1595: 
 1596:     bs_dict = qobject_to_qdict(obj);
 1597: 
 1598:     monitor_printf(mon, "%s: type=%s removable=%d",
 1599:                         qdict_get_str(bs_dict, "device"),
 1600:                         qdict_get_str(bs_dict, "type"),
 1601:                         qdict_get_bool(bs_dict, "removable"));
 1602: 
 1603:     if (qdict_get_bool(bs_dict, "removable")) {
 1604:         monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked"));
 1605:     }
 1606: 
 1607:     if (qdict_haskey(bs_dict, "inserted")) {
 1608:         QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted"));
 1609: 
 1610:         monitor_printf(mon, " file=");
 1611:         monitor_print_filename(mon, qdict_get_str(qdict, "file"));
 1612:         if (qdict_haskey(qdict, "backing_file")) {
 1613:             monitor_printf(mon, " backing_file=");
 1614:             monitor_print_filename(mon, qdict_get_str(qdict, "backing_file"));
 1615:         }
 1616:         monitor_printf(mon, " ro=%d drv=%s encrypted=%d",
 1617:                             qdict_get_bool(qdict, "ro"),
 1618:                             qdict_get_str(qdict, "drv"),
 1619:                             qdict_get_bool(qdict, "encrypted"));
 1620:     } else {
 1621:         monitor_printf(mon, " [not inserted]");
 1622:     }
 1623: 
 1624:     monitor_printf(mon, "\n");
 1625: }
 1626: 
 1627: void bdrv_info_print(Monitor *mon, const QObject *data)
 1628: {
 1629:     qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon);
 1630: }
 1631: 
 1632: void bdrv_info(Monitor *mon, QObject **ret_data)
 1633: {
 1634:     QList *bs_list;
 1635:     BlockDriverState *bs;
 1636: 
 1637:     bs_list = qlist_new();
 1638: 
 1639:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
 1640:         QObject *bs_obj;
 1641:         const char *type = "unknown";
 1642: 
 1643:         switch(bs->type) {
 1644:         case BDRV_TYPE_HD:
 1645:             type = "hd";
 1646:             break;
 1647:         case BDRV_TYPE_CDROM:
 1648:             type = "cdrom";
 1649:             break;
 1650:         case BDRV_TYPE_FLOPPY:
 1651:             type = "floppy";
 1652:             break;
 1653:         }
 1654: 
 1655:         bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': %s, "
 1656:                                     "'removable': %i, 'locked': %i }",
 1657:                                     bs->device_name, type, bs->removable,
 1658:                                     bs->locked);
 1659: 
 1660:         if (bs->drv) {
 1661:             QObject *obj;
 1662:             QDict *bs_dict = qobject_to_qdict(bs_obj);
 1663: 
 1664:             obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, "
 1665:                                      "'encrypted': %i }",
 1666:                                      bs->filename, bs->read_only,
 1667:                                      bs->drv->format_name,
 1668:                                      bdrv_is_encrypted(bs));
 1669:             if (bs->backing_file[0] != '\0') {
 1670:                 QDict *qdict = qobject_to_qdict(obj);
 1671:                 qdict_put(qdict, "backing_file",
 1672:                           qstring_from_str(bs->backing_file));
 1673:             }
 1674: 
 1675:             qdict_put_obj(bs_dict, "inserted", obj);
 1676:         }
 1677:         qlist_append_obj(bs_list, bs_obj);
 1678:     }
 1679: 
 1680:     *ret_data = QOBJECT(bs_list);
 1681: }
 1682: 
 1683: static void bdrv_stats_iter(QObject *data, void *opaque)
 1684: {
 1685:     QDict *qdict;
 1686:     Monitor *mon = opaque;
 1687: 
 1688:     qdict = qobject_to_qdict(data);
 1689:     monitor_printf(mon, "%s:", qdict_get_str(qdict, "device"));
 1690: 
 1691:     qdict = qobject_to_qdict(qdict_get(qdict, "stats"));
 1692:     monitor_printf(mon, " rd_bytes=%" PRId64
 1693:                         " wr_bytes=%" PRId64
 1694:                         " rd_operations=%" PRId64
 1695:                         " wr_operations=%" PRId64
 1696:                         "\n",
 1697:                         qdict_get_int(qdict, "rd_bytes"),
 1698:                         qdict_get_int(qdict, "wr_bytes"),
 1699:                         qdict_get_int(qdict, "rd_operations"),
 1700:                         qdict_get_int(qdict, "wr_operations"));
 1701: }
 1702: 
 1703: void bdrv_stats_print(Monitor *mon, const QObject *data)
 1704: {
 1705:     qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon);
 1706: }
 1707: 
 1708: static QObject* bdrv_info_stats_bs(BlockDriverState *bs)
 1709: {
 1710:     QObject *res;
 1711:     QDict *dict;
 1712: 
 1713:     res = qobject_from_jsonf("{ 'stats': {"
 1714:                              "'rd_bytes': %" PRId64 ","
 1715:                              "'wr_bytes': %" PRId64 ","
 1716:                              "'rd_operations': %" PRId64 ","
 1717:                              "'wr_operations': %" PRId64 ","
 1718:                              "'wr_highest_offset': %" PRId64
 1719:                              "} }",
 1720:                              bs->rd_bytes, bs->wr_bytes,
 1721:                              bs->rd_ops, bs->wr_ops,
 1722:                              bs->wr_highest_sector *
 1723:                              (uint64_t)BDRV_SECTOR_SIZE);
 1724:     dict  = qobject_to_qdict(res);
 1725: 
 1726:     if (*bs->device_name) {
 1727:         qdict_put(dict, "device", qstring_from_str(bs->device_name));
 1728:     }
 1729: 
 1730:     if (bs->file) {
 1731:         QObject *parent = bdrv_info_stats_bs(bs->file);
 1732:         qdict_put_obj(dict, "parent", parent);
 1733:     }
 1734: 
 1735:     return res;
 1736: }
 1737: 
 1738: void bdrv_info_stats(Monitor *mon, QObject **ret_data)
 1739: {
 1740:     QObject *obj;
 1741:     QList *devices;
 1742:     BlockDriverState *bs;
 1743: 
 1744:     devices = qlist_new();
 1745: 
 1746:     QTAILQ_FOREACH(bs, &bdrv_states, list) {
 1747:         obj = bdrv_info_stats_bs(bs);
 1748:         qlist_append_obj(devices, obj);
 1749:     }
 1750: 
 1751:     *ret_data = QOBJECT(devices);
 1752: }
 1753: 
 1754: const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
 1755: {
 1756:     if (bs->backing_hd && bs->backing_hd->encrypted)
 1757:         return bs->backing_file;
 1758:     else if (bs->encrypted)
 1759:         return bs->filename;
 1760:     else
 1761:         return NULL;
 1762: }
 1763: 
 1764: void bdrv_get_backing_filename(BlockDriverState *bs,
 1765:                                char *filename, int filename_size)
 1766: {
 1767:     if (!bs->backing_file) {
 1768:         pstrcpy(filename, filename_size, "");
 1769:     } else {
 1770:         pstrcpy(filename, filename_size, bs->backing_file);
 1771:     }
 1772: }
 1773: 
 1774: int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
 1775:                           const uint8_t *buf, int nb_sectors)
 1776: {
 1777:     BlockDriver *drv = bs->drv;
 1778:     if (!drv)
 1779:         return -ENOMEDIUM;
 1780:     if (!drv->bdrv_write_compressed)
 1781:         return -ENOTSUP;
 1782:     if (bdrv_check_request(bs, sector_num, nb_sectors))
 1783:         return -EIO;
 1784: 
 1785:     if (bs->dirty_bitmap) {
 1786:         set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
 1787:     }
 1788: 
 1789:     return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
 1790: }
 1791: 
 1792: int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 1793: {
 1794:     BlockDriver *drv = bs->drv;
 1795:     if (!drv)
 1796:         return -ENOMEDIUM;
 1797:     if (!drv->bdrv_get_info)
 1798:         return -ENOTSUP;
 1799:     memset(bdi, 0, sizeof(*bdi));
 1800:     return drv->bdrv_get_info(bs, bdi);
 1801: }
 1802: 
 1803: int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
 1804:                       int64_t pos, int size)
 1805: {
 1806:     BlockDriver *drv = bs->drv;
 1807:     if (!drv)
 1808:         return -ENOMEDIUM;
 1809:     if (drv->bdrv_save_vmstate)
 1810:         return drv->bdrv_save_vmstate(bs, buf, pos, size);
 1811:     if (bs->file)
 1812:         return bdrv_save_vmstate(bs->file, buf, pos, size);
 1813:     return -ENOTSUP;
 1814: }
 1815: 
 1816: int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
 1817:                       int64_t pos, int size)
 1818: {
 1819:     BlockDriver *drv = bs->drv;
 1820:     if (!drv)
 1821:         return -ENOMEDIUM;
 1822:     if (drv->bdrv_load_vmstate)
 1823:         return drv->bdrv_load_vmstate(bs, buf, pos, size);
 1824:     if (bs->file)
 1825:         return bdrv_load_vmstate(bs->file, buf, pos, size);
 1826:     return -ENOTSUP;
 1827: }
 1828: 
 1829: void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
 1830: {
 1831:     BlockDriver *drv = bs->drv;
 1832: 
 1833:     if (!drv || !drv->bdrv_debug_event) {
 1834:         return;
 1835:     }
 1836: 
 1837:     return drv->bdrv_debug_event(bs, event);
 1838: 
 1839: }
 1840: 
 1841: /**************************************************************/
 1842: /* handling of snapshots */
 1843: 
 1844: int bdrv_can_snapshot(BlockDriverState *bs)
 1845: {
 1846:     BlockDriver *drv = bs->drv;
 1847:     if (!drv || bdrv_is_removable(bs) || bdrv_is_read_only(bs)) {
 1848:         return 0;
 1849:     }
 1850: 
 1851:     if (!drv->bdrv_snapshot_create) {
 1852:         if (bs->file != NULL) {
 1853:             return bdrv_can_snapshot(bs->file);
 1854:         }
 1855:         return 0;
 1856:     }
 1857: 
 1858:     return 1;
 1859: }
 1860: 
 1861: int bdrv_is_snapshot(BlockDriverState *bs)
 1862: {
 1863:     return !!(bs->open_flags & BDRV_O_SNAPSHOT);
 1864: }
 1865: 
 1866: BlockDriverState *bdrv_snapshots(void)
 1867: {
 1868:     BlockDriverState *bs;
 1869: 
 1870:     if (bs_snapshots) {
 1871:         return bs_snapshots;
 1872:     }
 1873: 
 1874:     bs = NULL;
 1875:     while ((bs = bdrv_next(bs))) {
 1876:         if (bdrv_can_snapshot(bs)) {
 1877:             bs_snapshots = bs;
 1878:             return bs;
 1879:         }
 1880:     }
 1881:     return NULL;
 1882: }
 1883: 
 1884: int bdrv_snapshot_create(BlockDriverState *bs,
 1885:                          QEMUSnapshotInfo *sn_info)
 1886: {
 1887:     BlockDriver *drv = bs->drv;
 1888:     if (!drv)
 1889:         return -ENOMEDIUM;
 1890:     if (drv->bdrv_snapshot_create)
 1891:         return drv->bdrv_snapshot_create(bs, sn_info);
 1892:     if (bs->file)
 1893:         return bdrv_snapshot_create(bs->file, sn_info);
 1894:     return -ENOTSUP;
 1895: }
 1896: 
 1897: int bdrv_snapshot_goto(BlockDriverState *bs,
 1898:                        const char *snapshot_id)
 1899: {
 1900:     BlockDriver *drv = bs->drv;
 1901:     int ret, open_ret;
 1902: 
 1903:     if (!drv)
 1904:         return -ENOMEDIUM;
 1905:     if (drv->bdrv_snapshot_goto)
 1906:         return drv->bdrv_snapshot_goto(bs, snapshot_id);
 1907: 
 1908:     if (bs->file) {
 1909:         drv->bdrv_close(bs);
 1910:         ret = bdrv_snapshot_goto(bs->file, snapshot_id);
 1911:         open_ret = drv->bdrv_open(bs, bs->open_flags);
 1912:         if (open_ret < 0) {
 1913:             bdrv_delete(bs->file);
 1914:             bs->drv = NULL;
 1915:             return open_ret;
 1916:         }
 1917:         return ret;
 1918:     }
 1919: 
 1920:     return -ENOTSUP;
 1921: }
 1922: 
 1923: int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
 1924: {
 1925:     BlockDriver *drv = bs->drv;
 1926:     if (!drv)
 1927:         return -ENOMEDIUM;
 1928:     if (drv->bdrv_snapshot_delete)
 1929:         return drv->bdrv_snapshot_delete(bs, snapshot_id);
 1930:     if (bs->file)
 1931:         return bdrv_snapshot_delete(bs->file, snapshot_id);
 1932:     return -ENOTSUP;
 1933: }
 1934: 
 1935: int bdrv_snapshot_list(BlockDriverState *bs,
 1936:                        QEMUSnapshotInfo **psn_info)
 1937: {
 1938:     BlockDriver *drv = bs->drv;
 1939:     if (!drv)
 1940:         return -ENOMEDIUM;
 1941:     if (drv->bdrv_snapshot_list)
 1942:         return drv->bdrv_snapshot_list(bs, psn_info);
 1943:     if (bs->file)
 1944:         return bdrv_snapshot_list(bs->file, psn_info);
 1945:     return -ENOTSUP;
 1946: }
 1947: 
 1948: int bdrv_snapshot_load_tmp(BlockDriverState *bs,
 1949:         const char *snapshot_name)
 1950: {
 1951:     BlockDriver *drv = bs->drv;
 1952:     if (!drv) {
 1953:         return -ENOMEDIUM;
 1954:     }
 1955:     if (!bs->read_only) {
 1956:         return -EINVAL;
 1957:     }
 1958:     if (drv->bdrv_snapshot_load_tmp) {
 1959:         return drv->bdrv_snapshot_load_tmp(bs, snapshot_name);
 1960:     }
 1961:     return -ENOTSUP;
 1962: }
 1963: 
 1964: #define NB_SUFFIXES 4
 1965: 
 1966: char *get_human_readable_size(char *buf, int buf_size, int64_t size)
 1967: {
 1968:     static const char suffixes[NB_SUFFIXES] = "KMGT";
 1969:     int64_t base;
 1970:     int i;
 1971: 
 1972:     if (size <= 999) {
 1973:         snprintf(buf, buf_size, "%" PRId64, size);
 1974:     } else {
 1975:         base = 1024;
 1976:         for(i = 0; i < NB_SUFFIXES; i++) {
 1977:             if (size < (10 * base)) {
 1978:                 snprintf(buf, buf_size, "%0.1f%c",
 1979:                          (double)size / base,
 1980:                          suffixes[i]);
 1981:                 break;
 1982:             } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
 1983:                 snprintf(buf, buf_size, "%" PRId64 "%c",
 1984:                          ((size + (base >> 1)) / base),
 1985:                          suffixes[i]);
 1986:                 break;
 1987:             }
 1988:             base = base * 1024;
 1989:         }
 1990:     }
 1991:     return buf;
 1992: }
 1993: 
 1994: char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
 1995: {
 1996:     char buf1[128], date_buf[128], clock_buf[128];
 1997: #ifdef _WIN32
 1998:     struct tm *ptm;
 1999: #else
 2000:     struct tm tm;
 2001: #endif
 2002:     time_t ti;
 2003:     int64_t secs;
 2004: 
 2005:     if (!sn) {
 2006:         snprintf(buf, buf_size,
 2007:                  "%-10s%-20s%7s%20s%15s",
 2008:                  "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
 2009:     } else {
 2010:         ti = sn->date_sec;
 2011: #ifdef _WIN32
 2012:         ptm = localtime(&ti);
 2013:         strftime(date_buf, sizeof(date_buf),
 2014:                  "%Y-%m-%d %H:%M:%S", ptm);
 2015: #else
 2016:         localtime_r(&ti, &tm);
 2017:         strftime(date_buf, sizeof(date_buf),
 2018:                  "%Y-%m-%d %H:%M:%S", &tm);
 2019: #endif
 2020:         secs = sn->vm_clock_nsec / 1000000000;
 2021:         snprintf(clock_buf, sizeof(clock_buf),
 2022:                  "%02d:%02d:%02d.%03d",
 2023:                  (int)(secs / 3600),
 2024:                  (int)((secs / 60) % 60),
 2025:                  (int)(secs % 60),
 2026:                  (int)((sn->vm_clock_nsec / 1000000) % 1000));
 2027:         snprintf(buf, buf_size,
 2028:                  "%-10s%-20s%7s%20s%15s",
 2029:                  sn->id_str, sn->name,
 2030:                  get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
 2031:                  date_buf,
 2032:                  clock_buf);
 2033:     }
 2034:     return buf;
 2035: }
 2036: 
 2037: 
 2038: /**************************************************************/
 2039: /* async I/Os */
 2040: 
 2041: BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
 2042:                                  QEMUIOVector *qiov, int nb_sectors,
 2043:                                  BlockDriverCompletionFunc *cb, void *opaque)
 2044: {
 2045:     BlockDriver *drv = bs->drv;
 2046:     BlockDriverAIOCB *ret;
 2047: 
 2048:     trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);
 2049: 
 2050:     if (!drv)
 2051:         return NULL;
 2052:     if (bdrv_check_request(bs, sector_num, nb_sectors))
 2053:         return NULL;
 2054: 
 2055:     ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
 2056:                               cb, opaque);
 2057: 
 2058:     if (ret) {
 2059: 	/* Update stats even though technically transfer has not happened. */
 2060: 	bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
 2061: 	bs->rd_ops ++;
 2062:     }
 2063: 
 2064:     return ret;
 2065: }
 2066: 
 2067: typedef struct BlockCompleteData {
 2068:     BlockDriverCompletionFunc *cb;
 2069:     void *opaque;
 2070:     BlockDriverState *bs;
 2071:     int64_t sector_num;
 2072:     int nb_sectors;
 2073: } BlockCompleteData;
 2074: 
 2075: static void block_complete_cb(void *opaque, int ret)
 2076: {
 2077:     BlockCompleteData *b = opaque;
 2078: 
 2079:     if (b->bs->dirty_bitmap) {
 2080:         set_dirty_bitmap(b->bs, b->sector_num, b->nb_sectors, 1);
 2081:     }
 2082:     b->cb(b->opaque, ret);
 2083:     qemu_free(b);
 2084: }
 2085: 
 2086: static BlockCompleteData *blk_dirty_cb_alloc(BlockDriverState *bs,
 2087:                                              int64_t sector_num,
 2088:                                              int nb_sectors,
 2089:                                              BlockDriverCompletionFunc *cb,
 2090:                                              void *opaque)
 2091: {
 2092:     BlockCompleteData *blkdata = qemu_mallocz(sizeof(BlockCompleteData));
 2093: 
 2094:     blkdata->bs = bs;
 2095:     blkdata->cb = cb;
 2096:     blkdata->opaque = opaque;
 2097:     blkdata->sector_num = sector_num;
 2098:     blkdata->nb_sectors = nb_sectors;
 2099: 
 2100:     return blkdata;
 2101: }
 2102: 
 2103: BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
 2104:                                   QEMUIOVector *qiov, int nb_sectors,
 2105:                                   BlockDriverCompletionFunc *cb, void *opaque)
 2106: {
 2107:     BlockDriver *drv = bs->drv;
 2108:     BlockDriverAIOCB *ret;
 2109:     BlockCompleteData *blk_cb_data;
 2110: 
 2111:     trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque);
 2112: 
 2113:     if (!drv)
 2114:         return NULL;
 2115:     if (bs->read_only)
 2116:         return NULL;
 2117:     if (bdrv_check_request(bs, sector_num, nb_sectors))
 2118:         return NULL;
 2119: 
 2120:     if (bs->dirty_bitmap) {
 2121:         blk_cb_data = blk_dirty_cb_alloc(bs, sector_num, nb_sectors, cb,
 2122:                                          opaque);
 2123:         cb = &block_complete_cb;
 2124:         opaque = blk_cb_data;
 2125:     }
 2126: 
 2127:     ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors,
 2128:                                cb, opaque);
 2129: 
 2130:     if (ret) {
 2131:         /* Update stats even though technically transfer has not happened. */
 2132:         bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
 2133:         bs->wr_ops ++;
 2134:         if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
 2135:             bs->wr_highest_sector = sector_num + nb_sectors - 1;
 2136:         }
 2137:     }
 2138: 
 2139:     return ret;
 2140: }
 2141: 
 2142: 
 2143: typedef struct MultiwriteCB {
 2144:     int error;
 2145:     int num_requests;
 2146:     int num_callbacks;
 2147:     struct {
 2148:         BlockDriverCompletionFunc *cb;
 2149:         void *opaque;
 2150:         QEMUIOVector *free_qiov;
 2151:         void *free_buf;
 2152:     } callbacks[];
 2153: } MultiwriteCB;
 2154: 
 2155: static void multiwrite_user_cb(MultiwriteCB *mcb)
 2156: {
 2157:     int i;
 2158: 
 2159:     for (i = 0; i < mcb->num_callbacks; i++) {
 2160:         mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error);
 2161:         if (mcb->callbacks[i].free_qiov) {
 2162:             qemu_iovec_destroy(mcb->callbacks[i].free_qiov);
 2163:         }
 2164:         qemu_free(mcb->callbacks[i].free_qiov);
 2165:         qemu_vfree(mcb->callbacks[i].free_buf);
 2166:     }
 2167: }
 2168: 
 2169: static void multiwrite_cb(void *opaque, int ret)
 2170: {
 2171:     MultiwriteCB *mcb = opaque;
 2172: 
 2173:     trace_multiwrite_cb(mcb, ret);
 2174: 
 2175:     if (ret < 0 && !mcb->error) {
 2176:         mcb->error = ret;
 2177:     }
 2178: 
 2179:     mcb->num_requests--;
 2180:     if (mcb->num_requests == 0) {
 2181:         multiwrite_user_cb(mcb);
 2182:         qemu_free(mcb);
 2183:     }
 2184: }
 2185: 
 2186: static int multiwrite_req_compare(const void *a, const void *b)
 2187: {
 2188:     const BlockRequest *req1 = a, *req2 = b;
 2189: 
 2190:     /*
 2191:      * Note that we can't simply subtract req2->sector from req1->sector
 2192:      * here as that could overflow the return value.
 2193:      */
 2194:     if (req1->sector > req2->sector) {
 2195:         return 1;
 2196:     } else if (req1->sector < req2->sector) {
 2197:         return -1;
 2198:     } else {
 2199:         return 0;
 2200:     }
 2201: }
 2202: 
 2203: /*
 2204:  * Takes a bunch of requests and tries to merge them. Returns the number of
 2205:  * requests that remain after merging.
 2206:  */
 2207: static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
 2208:     int num_reqs, MultiwriteCB *mcb)
 2209: {
 2210:     int i, outidx;
 2211: 
 2212:     // Sort requests by start sector
 2213:     qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
 2214: 
 2215:     // Check if adjacent requests touch the same clusters. If so, combine them,
 2216:     // filling up gaps with zero sectors.
 2217:     outidx = 0;
 2218:     for (i = 1; i < num_reqs; i++) {
 2219:         int merge = 0;
 2220:         int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors;
 2221: 
 2222:         // This handles the cases that are valid for all block drivers, namely
 2223:         // exactly sequential writes and overlapping writes.
 2224:         if (reqs[i].sector <= oldreq_last) {
 2225:             merge = 1;
 2226:         }
 2227: 
 2228:         // The block driver may decide that it makes sense to combine requests
 2229:         // even if there is a gap of some sectors between them. In this case,
 2230:         // the gap is filled with zeros (therefore only applicable for yet
 2231:         // unused space in format like qcow2).
 2232:         if (!merge && bs->drv->bdrv_merge_requests) {
 2233:             merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]);
 2234:         }
 2235: 
 2236:         if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) {
 2237:             merge = 0;
 2238:         }
 2239: 
 2240:         if (merge) {
 2241:             size_t size;
 2242:             QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov));
 2243:             qemu_iovec_init(qiov,
 2244:                 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
 2245: 
 2246:             // Add the first request to the merged one. If the requests are
 2247:             // overlapping, drop the last sectors of the first request.
 2248:             size = (reqs[i].sector - reqs[outidx].sector) << 9;
 2249:             qemu_iovec_concat(qiov, reqs[outidx].qiov, size);
 2250: 
 2251:             // We might need to add some zeros between the two requests
 2252:             if (reqs[i].sector > oldreq_last) {
 2253:                 size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9;
 2254:                 uint8_t *buf = qemu_blockalign(bs, zero_bytes);
 2255:                 memset(buf, 0, zero_bytes);
 2256:                 qemu_iovec_add(qiov, buf, zero_bytes);
 2257:                 mcb->callbacks[i].free_buf = buf;
 2258:             }
 2259: 
 2260:             // Add the second request
 2261:             qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size);
 2262: 
 2263:             reqs[outidx].nb_sectors = qiov->size >> 9;
 2264:             reqs[outidx].qiov = qiov;
 2265: 
 2266:             mcb->callbacks[i].free_qiov = reqs[outidx].qiov;
 2267:         } else {
 2268:             outidx++;
 2269:             reqs[outidx].sector     = reqs[i].sector;
 2270:             reqs[outidx].nb_sectors = reqs[i].nb_sectors;
 2271:             reqs[outidx].qiov       = reqs[i].qiov;
 2272:         }
 2273:     }
 2274: 
 2275:     return outidx + 1;
 2276: }
 2277: 
 2278: /*
 2279:  * Submit multiple AIO write requests at once.
 2280:  *
 2281:  * On success, the function returns 0 and all requests in the reqs array have
 2282:  * been submitted. In error case this function returns -1, and any of the
 2283:  * requests may or may not be submitted yet. In particular, this means that the
 2284:  * callback will be called for some of the requests, for others it won't. The
 2285:  * caller must check the error field of the BlockRequest to wait for the right
 2286:  * callbacks (if error != 0, no callback will be called).
 2287:  *
 2288:  * The implementation may modify the contents of the reqs array, e.g. to merge
 2289:  * requests. However, the fields opaque and error are left unmodified as they
 2290:  * are used to signal failure for a single request to the caller.
 2291:  */
 2292: int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs)
 2293: {
 2294:     BlockDriverAIOCB *acb;
 2295:     MultiwriteCB *mcb;
 2296:     int i;
 2297: 
 2298:     if (num_reqs == 0) {
 2299:         return 0;
 2300:     }
 2301: 
 2302:     // Create MultiwriteCB structure
 2303:     mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks));
 2304:     mcb->num_requests = 0;
 2305:     mcb->num_callbacks = num_reqs;
 2306: 
 2307:     for (i = 0; i < num_reqs; i++) {
 2308:         mcb->callbacks[i].cb = reqs[i].cb;
 2309:         mcb->callbacks[i].opaque = reqs[i].opaque;
 2310:     }
 2311: 
 2312:     // Check for mergable requests
 2313:     num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
 2314: 
 2315:     trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs);
 2316: 
 2317:     /*
 2318:      * Run the aio requests. As soon as one request can't be submitted
 2319:      * successfully, fail all requests that are not yet submitted (we must
 2320:      * return failure for all requests anyway)
 2321:      *
 2322:      * num_requests cannot be set to the right value immediately: If
 2323:      * bdrv_aio_writev fails for some request, num_requests would be too high
 2324:      * and therefore multiwrite_cb() would never recognize the multiwrite
 2325:      * request as completed. We also cannot use the loop variable i to set it
 2326:      * when the first request fails because the callback may already have been
 2327:      * called for previously submitted requests. Thus, num_requests must be
 2328:      * incremented for each request that is submitted.
 2329:      *
 2330:      * The problem that callbacks may be called early also means that we need
 2331:      * to take care that num_requests doesn't become 0 before all requests are
 2332:      * submitted - multiwrite_cb() would consider the multiwrite request
 2333:      * completed. A dummy request that is "completed" by a manual call to
 2334:      * multiwrite_cb() takes care of this.
 2335:      */
 2336:     mcb->num_requests = 1;
 2337: 
 2338:     // Run the aio requests
 2339:     for (i = 0; i < num_reqs; i++) {
 2340:         mcb->num_requests++;
 2341:         acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov,
 2342:             reqs[i].nb_sectors, multiwrite_cb, mcb);
 2343: 
 2344:         if (acb == NULL) {
 2345:             // We can only fail the whole thing if no request has been
 2346:             // submitted yet. Otherwise we'll wait for the submitted AIOs to
 2347:             // complete and report the error in the callback.
 2348:             if (i == 0) {
 2349:                 trace_bdrv_aio_multiwrite_earlyfail(mcb);
 2350:                 goto fail;
 2351:             } else {
 2352:                 trace_bdrv_aio_multiwrite_latefail(mcb, i);
 2353:                 multiwrite_cb(mcb, -EIO);
 2354:                 break;
 2355:             }
 2356:         }
 2357:     }
 2358: 
 2359:     /* Complete the dummy request */
 2360:     multiwrite_cb(mcb, 0);
 2361: 
 2362:     return 0;
 2363: 
 2364: fail:
 2365:     for (i = 0; i < mcb->num_callbacks; i++) {
 2366:         reqs[i].error = -EIO;
 2367:     }
 2368:     qemu_free(mcb);
 2369:     return -1;
 2370: }
 2371: 
 2372: BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
 2373:         BlockDriverCompletionFunc *cb, void *opaque)
 2374: {
 2375:     BlockDriver *drv = bs->drv;
 2376: 
 2377:     if (bs->open_flags & BDRV_O_NO_FLUSH) {
 2378:         return bdrv_aio_noop_em(bs, cb, opaque);
 2379:     }
 2380: 
 2381:     if (!drv)
 2382:         return NULL;
 2383:     return drv->bdrv_aio_flush(bs, cb, opaque);
 2384: }
 2385: 
 2386: void bdrv_aio_cancel(BlockDriverAIOCB *acb)
 2387: {
 2388:     acb->pool->cancel(acb);
 2389: }
 2390: 
 2391: 
 2392: /**************************************************************/
 2393: /* async block device emulation */
 2394: 
 2395: typedef struct BlockDriverAIOCBSync {
 2396:     BlockDriverAIOCB common;
 2397:     QEMUBH *bh;
 2398:     int ret;
 2399:     /* vector translation state */
 2400:     QEMUIOVector *qiov;
 2401:     uint8_t *bounce;
 2402:     int is_write;
 2403: } BlockDriverAIOCBSync;
 2404: 
 2405: static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
 2406: {
 2407:     BlockDriverAIOCBSync *acb =
 2408:         container_of(blockacb, BlockDriverAIOCBSync, common);
 2409:     qemu_bh_delete(acb->bh);
 2410:     acb->bh = NULL;
 2411:     qemu_aio_release(acb);
 2412: }
 2413: 
 2414: static AIOPool bdrv_em_aio_pool = {
 2415:     .aiocb_size         = sizeof(BlockDriverAIOCBSync),
 2416:     .cancel             = bdrv_aio_cancel_em,
 2417: };
 2418: 
 2419: static void bdrv_aio_bh_cb(void *opaque)
 2420: {
 2421:     BlockDriverAIOCBSync *acb = opaque;
 2422: 
 2423:     if (!acb->is_write)
 2424:         qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size);
 2425:     qemu_vfree(acb->bounce);
 2426:     acb->common.cb(acb->common.opaque, acb->ret);
 2427:     qemu_bh_delete(acb->bh);
 2428:     acb->bh = NULL;
 2429:     qemu_aio_release(acb);
 2430: }
 2431: 
 2432: static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
 2433:                                             int64_t sector_num,
 2434:                                             QEMUIOVector *qiov,
 2435:                                             int nb_sectors,
 2436:                                             BlockDriverCompletionFunc *cb,
 2437:                                             void *opaque,
 2438:                                             int is_write)
 2439: 
 2440: {
 2441:     BlockDriverAIOCBSync *acb;
 2442: 
 2443:     acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
 2444:     acb->is_write = is_write;
 2445:     acb->qiov = qiov;
 2446:     acb->bounce = qemu_blockalign(bs, qiov->size);
 2447: 
 2448:     if (!acb->bh)
 2449:         acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
 2450: 
 2451:     if (is_write) {
 2452:         qemu_iovec_to_buffer(acb->qiov, acb->bounce);
 2453:         acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
 2454:     } else {
 2455:         acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
 2456:     }
 2457: 
 2458:     qemu_bh_schedule(acb->bh);
 2459: 
 2460:     return &acb->common;
 2461: }
 2462: 
 2463: static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
 2464:         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 2465:         BlockDriverCompletionFunc *cb, void *opaque)
 2466: {
 2467:     return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
 2468: }
 2469: 
 2470: static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
 2471:         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 2472:         BlockDriverCompletionFunc *cb, void *opaque)
 2473: {
 2474:     return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
 2475: }
 2476: 
 2477: static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
 2478:         BlockDriverCompletionFunc *cb, void *opaque)
 2479: {
 2480:     BlockDriverAIOCBSync *acb;
 2481: 
 2482:     acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
 2483:     acb->is_write = 1; /* don't bounce in the completion hadler */
 2484:     acb->qiov = NULL;
 2485:     acb->bounce = NULL;
 2486:     acb->ret = 0;
 2487: 
 2488:     if (!acb->bh)
 2489:         acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
 2490: 
 2491:     bdrv_flush(bs);
 2492:     qemu_bh_schedule(acb->bh);
 2493:     return &acb->common;
 2494: }
 2495: 
 2496: static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs,
 2497:         BlockDriverCompletionFunc *cb, void *opaque)
 2498: {
 2499:     BlockDriverAIOCBSync *acb;
 2500: 
 2501:     acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
 2502:     acb->is_write = 1; /* don't bounce in the completion handler */
 2503:     acb->qiov = NULL;
 2504:     acb->bounce = NULL;
 2505:     acb->ret = 0;
 2506: 
 2507:     if (!acb->bh) {
 2508:         acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
 2509:     }
 2510: 
 2511:     qemu_bh_schedule(acb->bh);
 2512:     return &acb->common;
 2513: }
 2514: 
 2515: /**************************************************************/
 2516: /* sync block device emulation */
 2517: 
 2518: static void bdrv_rw_em_cb(void *opaque, int ret)
 2519: {
 2520:     *(int *)opaque = ret;
 2521: }
 2522: 
 2523: #define NOT_DONE 0x7fffffff
 2524: 
 2525: static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
 2526:                         uint8_t *buf, int nb_sectors)
 2527: {
 2528:     int async_ret;
 2529:     BlockDriverAIOCB *acb;
 2530:     struct iovec iov;
 2531:     QEMUIOVector qiov;
 2532: 
 2533:     async_context_push();
 2534: 
 2535:     async_ret = NOT_DONE;
 2536:     iov.iov_base = (void *)buf;
 2537:     iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
 2538:     qemu_iovec_init_external(&qiov, &iov, 1);
 2539:     acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors,
 2540:         bdrv_rw_em_cb, &async_ret);
 2541:     if (acb == NULL) {
 2542:         async_ret = -1;
 2543:         goto fail;
 2544:     }
 2545: 
 2546:     while (async_ret == NOT_DONE) {
 2547:         qemu_aio_wait();
 2548:     }
 2549: 
 2550: 
 2551: fail:
 2552:     async_context_pop();
 2553:     return async_ret;
 2554: }
 2555: 
 2556: static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
 2557:                          const uint8_t *buf, int nb_sectors)
 2558: {
 2559:     int async_ret;
 2560:     BlockDriverAIOCB *acb;
 2561:     struct iovec iov;
 2562:     QEMUIOVector qiov;
 2563: 
 2564:     async_context_push();
 2565: 
 2566:     async_ret = NOT_DONE;
 2567:     iov.iov_base = (void *)buf;
 2568:     iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
 2569:     qemu_iovec_init_external(&qiov, &iov, 1);
 2570:     acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors,
 2571:         bdrv_rw_em_cb, &async_ret);
 2572:     if (acb == NULL) {
 2573:         async_ret = -1;
 2574:         goto fail;
 2575:     }
 2576:     while (async_ret == NOT_DONE) {
 2577:         qemu_aio_wait();
 2578:     }
 2579: 
 2580: fail:
 2581:     async_context_pop();
 2582:     return async_ret;
 2583: }
 2584: 
 2585: void bdrv_init(void)
 2586: {
 2587:     module_call_init(MODULE_INIT_BLOCK);
 2588: }
 2589: 
 2590: void bdrv_init_with_whitelist(void)
 2591: {
 2592:     use_bdrv_whitelist = 1;
 2593:     bdrv_init();
 2594: }
 2595: 
 2596: void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
 2597:                    BlockDriverCompletionFunc *cb, void *opaque)
 2598: {
 2599:     BlockDriverAIOCB *acb;
 2600: 
 2601:     if (pool->free_aiocb) {
 2602:         acb = pool->free_aiocb;
 2603:         pool->free_aiocb = acb->next;
 2604:     } else {
 2605:         acb = qemu_mallocz(pool->aiocb_size);
 2606:         acb->pool = pool;
 2607:     }
 2608:     acb->bs = bs;
 2609:     acb->cb = cb;
 2610:     acb->opaque = opaque;
 2611:     return acb;
 2612: }
 2613: 
 2614: void qemu_aio_release(void *p)
 2615: {
 2616:     BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p;
 2617:     AIOPool *pool = acb->pool;
 2618:     acb->next = pool->free_aiocb;
 2619:     pool->free_aiocb = acb;
 2620: }
 2621: 
 2622: /**************************************************************/
 2623: /* removable device support */
 2624: 
 2625: /**
 2626:  * Return TRUE if the media is present
 2627:  */
 2628: int bdrv_is_inserted(BlockDriverState *bs)
 2629: {
 2630:     BlockDriver *drv = bs->drv;
 2631:     int ret;
 2632:     if (!drv)
 2633:         return 0;
 2634:     if (!drv->bdrv_is_inserted)
 2635:         return !bs->tray_open;
 2636:     ret = drv->bdrv_is_inserted(bs);
 2637:     return ret;
 2638: }
 2639: 
 2640: /**
 2641:  * Return TRUE if the media changed since the last call to this
 2642:  * function. It is currently only used for floppy disks
 2643:  */
 2644: int bdrv_media_changed(BlockDriverState *bs)
 2645: {
 2646:     BlockDriver *drv = bs->drv;
 2647:     int ret;
 2648: 
 2649:     if (!drv || !drv->bdrv_media_changed)
 2650:         ret = -ENOTSUP;
 2651:     else
 2652:         ret = drv->bdrv_media_changed(bs);
 2653:     if (ret == -ENOTSUP)
 2654:         ret = bs->media_changed;
 2655:     bs->media_changed = 0;
 2656:     return ret;
 2657: }
 2658: 
 2659: /**
 2660:  * If eject_flag is TRUE, eject the media. Otherwise, close the tray
 2661:  */
 2662: int bdrv_eject(BlockDriverState *bs, int eject_flag)
 2663: {
 2664:     BlockDriver *drv = bs->drv;
 2665:     int ret;
 2666: 
 2667:     if (bs->locked) {
 2668:         return -EBUSY;
 2669:     }
 2670: 
 2671:     if (!drv || !drv->bdrv_eject) {
 2672:         ret = -ENOTSUP;
 2673:     } else {
 2674:         ret = drv->bdrv_eject(bs, eject_flag);
 2675:     }
 2676:     if (ret == -ENOTSUP) {
 2677:         ret = 0;
 2678:     }
 2679:     if (ret >= 0) {
 2680:         bs->tray_open = eject_flag;
 2681:     }
 2682: 
 2683:     return ret;
 2684: }
 2685: 
 2686: int bdrv_is_locked(BlockDriverState *bs)
 2687: {
 2688:     return bs->locked;
 2689: }
 2690: 
 2691: /**
 2692:  * Lock or unlock the media (if it is locked, the user won't be able
 2693:  * to eject it manually).
 2694:  */
 2695: void bdrv_set_locked(BlockDriverState *bs, int locked)
 2696: {
 2697:     BlockDriver *drv = bs->drv;
 2698: 
 2699:     bs->locked = locked;
 2700:     if (drv && drv->bdrv_set_locked) {
 2701:         drv->bdrv_set_locked(bs, locked);
 2702:     }
 2703: }
 2704: 
 2705: /* needed for generic scsi interface */
 2706: 
 2707: int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
 2708: {
 2709:     BlockDriver *drv = bs->drv;
 2710: 
 2711:     if (drv && drv->bdrv_ioctl)
 2712:         return drv->bdrv_ioctl(bs, req, buf);
 2713:     return -ENOTSUP;
 2714: }
 2715: 
 2716: BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
 2717:         unsigned long int req, void *buf,
 2718:         BlockDriverCompletionFunc *cb, void *opaque)
 2719: {
 2720:     BlockDriver *drv = bs->drv;
 2721: 
 2722:     if (drv && drv->bdrv_aio_ioctl)
 2723:         return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
 2724:     return NULL;
 2725: }
 2726: 
 2727: 
 2728: 
 2729: void *qemu_blockalign(BlockDriverState *bs, size_t size)
 2730: {
 2731:     return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
 2732: }
 2733: 
 2734: void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable)
 2735: {
 2736:     int64_t bitmap_size;
 2737: 
 2738:     bs->dirty_count = 0;
 2739:     if (enable) {
 2740:         if (!bs->dirty_bitmap) {
 2741:             bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
 2742:                     BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
 2743:             bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
 2744: 
 2745:             bs->dirty_bitmap = qemu_mallocz(bitmap_size);
 2746:         }
 2747:     } else {
 2748:         if (bs->dirty_bitmap) {
 2749:             qemu_free(bs->dirty_bitmap);
 2750:             bs->dirty_bitmap = NULL;
 2751:         }
 2752:     }
 2753: }
 2754: 
 2755: int bdrv_get_dirty(BlockDriverState *bs, int64_t sector)
 2756: {
 2757:     int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
 2758: 
 2759:     if (bs->dirty_bitmap &&
 2760:         (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) {
 2761:         return !!(bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] &
 2762:             (1UL << (chunk % (sizeof(unsigned long) * 8))));
 2763:     } else {
 2764:         return 0;
 2765:     }
 2766: }
 2767: 
 2768: void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
 2769:                       int nr_sectors)
 2770: {
 2771:     set_dirty_bitmap(bs, cur_sector, nr_sectors, 0);
 2772: }
 2773: 
 2774: int64_t bdrv_get_dirty_count(BlockDriverState *bs)
 2775: {
 2776:     return bs->dirty_count;
 2777: }
 2778: 
 2779: void bdrv_set_in_use(BlockDriverState *bs, int in_use)
 2780: {
 2781:     assert(bs->in_use != in_use);
 2782:     bs->in_use = in_use;
 2783: }
 2784: 
 2785: int bdrv_in_use(BlockDriverState *bs)
 2786: {
 2787:     return bs->in_use;
 2788: }
 2789: 
 2790: int bdrv_img_create(const char *filename, const char *fmt,
 2791:                     const char *base_filename, const char *base_fmt,
 2792:                     char *options, uint64_t img_size, int flags)
 2793: {
 2794:     QEMUOptionParameter *param = NULL, *create_options = NULL;
 2795:     QEMUOptionParameter *backing_fmt, *backing_file;
 2796:     BlockDriverState *bs = NULL;
 2797:     BlockDriver *drv, *proto_drv;
 2798:     BlockDriver *backing_drv = NULL;
 2799:     int ret = 0;
 2800: 
 2801:     /* Find driver and parse its options */
 2802:     drv = bdrv_find_format(fmt);
 2803:     if (!drv) {
 2804:         error_report("Unknown file format '%s'", fmt);
 2805:         ret = -EINVAL;
 2806:         goto out;
 2807:     }
 2808: 
 2809:     proto_drv = bdrv_find_protocol(filename);
 2810:     if (!proto_drv) {
 2811:         error_report("Unknown protocol '%s'", filename);
 2812:         ret = -EINVAL;
 2813:         goto out;
 2814:     }
 2815: 
 2816:     create_options = append_option_parameters(create_options,
 2817:                                               drv->create_options);
 2818:     create_options = append_option_parameters(create_options,
 2819:                                               proto_drv->create_options);
 2820: 
 2821:     /* Create parameter list with default values */
 2822:     param = parse_option_parameters("", create_options, param);
 2823: 
 2824:     set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size);
 2825: 
 2826:     /* Parse -o options */
 2827:     if (options) {
 2828:         param = parse_option_parameters(options, create_options, param);
 2829:         if (param == NULL) {
 2830:             error_report("Invalid options for file format '%s'.", fmt);
 2831:             ret = -EINVAL;
 2832:             goto out;
 2833:         }
 2834:     }
 2835: 
 2836:     if (base_filename) {
 2837:         if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE,
 2838:                                  base_filename)) {
 2839:             error_report("Backing file not supported for file format '%s'",
 2840:                          fmt);
 2841:             ret = -EINVAL;
 2842:             goto out;
 2843:         }
 2844:     }
 2845: 
 2846:     if (base_fmt) {
 2847:         if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) {
 2848:             error_report("Backing file format not supported for file "
 2849:                          "format '%s'", fmt);
 2850:             ret = -EINVAL;
 2851:             goto out;
 2852:         }
 2853:     }
 2854: 
 2855:     backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
 2856:     if (backing_file && backing_file->value.s) {
 2857:         if (!strcmp(filename, backing_file->value.s)) {
 2858:             error_report("Error: Trying to create an image with the "
 2859:                          "same filename as the backing file");
 2860:             ret = -EINVAL;
 2861:             goto out;
 2862:         }
 2863:     }
 2864: 
 2865:     backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT);
 2866:     if (backing_fmt && backing_fmt->value.s) {
 2867:         backing_drv = bdrv_find_format(backing_fmt->value.s);
 2868:         if (!backing_drv) {
 2869:             error_report("Unknown backing file format '%s'",
 2870:                          backing_fmt->value.s);
 2871:             ret = -EINVAL;
 2872:             goto out;
 2873:         }
 2874:     }
 2875: 
 2876:     // The size for the image must always be specified, with one exception:
 2877:     // If we are using a backing file, we can obtain the size from there
 2878:     if (get_option_parameter(param, BLOCK_OPT_SIZE)->value.n == -1) {
 2879:         if (backing_file && backing_file->value.s) {
 2880:             uint64_t size;
 2881:             char buf[32];
 2882: 
 2883:             bs = bdrv_new("");
 2884: 
 2885:             ret = bdrv_open(bs, backing_file->value.s, flags, backing_drv);
 2886:             if (ret < 0) {
 2887:                 error_report("Could not open '%s'", backing_file->value.s);
 2888:                 goto out;
 2889:             }
 2890:             bdrv_get_geometry(bs, &size);
 2891:             size *= 512;
 2892: 
 2893:             snprintf(buf, sizeof(buf), "%" PRId64, size);
 2894:             set_option_parameter(param, BLOCK_OPT_SIZE, buf);
 2895:         } else {
 2896:             error_report("Image creation needs a size parameter");
 2897:             ret = -EINVAL;
 2898:             goto out;
 2899:         }
 2900:     }
 2901: 
 2902:     printf("Formatting '%s', fmt=%s ", filename, fmt);
 2903:     print_option_parameters(param);
 2904:     puts("");
 2905: 
 2906:     ret = bdrv_create(drv, filename, param);
 2907: 
 2908:     if (ret < 0) {
 2909:         if (ret == -ENOTSUP) {
 2910:             error_report("Formatting or formatting option not supported for "
 2911:                          "file format '%s'", fmt);
 2912:         } else if (ret == -EFBIG) {
 2913:             error_report("The image size is too large for file format '%s'",
 2914:                          fmt);
 2915:         } else {
 2916:             error_report("%s: error while creating %s: %s", filename, fmt,
 2917:                          strerror(-ret));
 2918:         }
 2919:     }
 2920: 
 2921: out:
 2922:     free_option_parameters(create_options);
 2923:     free_option_parameters(param);
 2924: 
 2925:     if (bs) {
 2926:         bdrv_delete(bs);
 2927:     }
 2928: 
 2929:     return ret;
 2930: }

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