Commit 927f11e1 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

file-posix: Support .bdrv_co_create 



This adds the .bdrv_co_create driver callback to file, which enables
image creation over QMP.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
parent b0292b85

block/file-posix.c

+56 −23
Original line number Diff line number Diff line
@@ -1982,34 +1982,25 @@ static int64_t raw_get_allocated_file_size(BlockDriverState *bs) 
    return (int64_t)st.st_blocks * 512;

}



static int coroutine_fn raw_co_create_opts(const char *filename, QemuOpts *opts,

                                           Error **errp)

static int raw_co_create(BlockdevCreateOptions *options, Error **errp)

{

    BlockdevCreateOptionsFile *file_opts;

    int fd;

    int result = 0;

    int64_t total_size = 0;

    bool nocow = false;

    PreallocMode prealloc;

    char *buf = NULL;

    Error *local_err = NULL;



    strstart(filename, "file:", &filename);

    /* Validate options and set default values */

    assert(options->driver == BLOCKDEV_DRIVER_FILE);

    file_opts = &options->u.file;



    /* Read out options */

    total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),

                          BDRV_SECTOR_SIZE);

    nocow = qemu_opt_get_bool(opts, BLOCK_OPT_NOCOW, false);

    buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);

    prealloc = qapi_enum_parse(&PreallocMode_lookup, buf,

                               PREALLOC_MODE_OFF, &local_err);

    g_free(buf);

    if (local_err) {

        error_propagate(errp, local_err);

        result = -EINVAL;

        goto out;

    if (!file_opts->has_nocow) {

        file_opts->nocow = false;

    }

    if (!file_opts->has_preallocation) {

        file_opts->preallocation = PREALLOC_MODE_OFF;

    }



    fd = qemu_open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY,

    /* Create file */

    fd = qemu_open(file_opts->filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY,

                   0644);

    if (fd < 0) {

        result = -errno;
@@ -2017,7 +2008,7 @@ static int coroutine_fn raw_co_create_opts(const char *filename, QemuOpts *opts, 
        goto out;

    }



    if (nocow) {

    if (file_opts->nocow) {

#ifdef __linux__

        /* Set NOCOW flag to solve performance issue on fs like btrfs.

         * This is an optimisation. The FS_IOC_SETFLAGS ioctl return value
@@ -2032,7 +2023,8 @@ static int coroutine_fn raw_co_create_opts(const char *filename, QemuOpts *opts, 
#endif

    }



    result = raw_regular_truncate(fd, total_size, prealloc, errp);

    result = raw_regular_truncate(fd, file_opts->size, file_opts->preallocation,

                                  errp);

    if (result < 0) {

        goto out_close;

    }
@@ -2046,6 +2038,46 @@ out: 
    return result;

}



static int coroutine_fn raw_co_create_opts(const char *filename, QemuOpts *opts,

                                           Error **errp)

{

    BlockdevCreateOptions options;

    int64_t total_size = 0;

    bool nocow = false;

    PreallocMode prealloc;

    char *buf = NULL;

    Error *local_err = NULL;



    /* Skip file: protocol prefix */

    strstart(filename, "file:", &filename);



    /* Read out options */

    total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),

                          BDRV_SECTOR_SIZE);

    nocow = qemu_opt_get_bool(opts, BLOCK_OPT_NOCOW, false);

    buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);

    prealloc = qapi_enum_parse(&PreallocMode_lookup, buf,

                               PREALLOC_MODE_OFF, &local_err);

    g_free(buf);

    if (local_err) {

        error_propagate(errp, local_err);

        return -EINVAL;

    }



    options = (BlockdevCreateOptions) {

        .driver     = BLOCKDEV_DRIVER_FILE,

        .u.file     = {

            .filename           = (char *) filename,

            .size               = total_size,

            .has_preallocation  = true,

            .preallocation      = prealloc,

            .has_nocow          = true,

            .nocow              = nocow,

        },

    };

    return raw_co_create(&options, errp);

}



/*

 * Find allocation range in @bs around offset @start.

 * May change underlying file descriptor's file offset.
@@ -2277,6 +2309,7 @@ BlockDriver bdrv_file = { 
    .bdrv_reopen_commit = raw_reopen_commit,

    .bdrv_reopen_abort = raw_reopen_abort,

    .bdrv_close = raw_close,

    .bdrv_co_create = raw_co_create,

    .bdrv_co_create_opts = raw_co_create_opts,

    .bdrv_has_zero_init = bdrv_has_zero_init_1,

    .bdrv_co_block_status = raw_co_block_status,

qapi/block-core.json

+19 −1
Original line number Diff line number Diff line
@@ -3358,6 +3358,24 @@ 
##

{ 'command': 'blockdev-del', 'data': { 'node-name': 'str' } }



##

# @BlockdevCreateOptionsFile:

#

# Driver specific image creation options for file.

#

# @filename         Filename for the new image file

# @size             Size of the virtual disk in bytes

# @preallocation    Preallocation mode for the new image (default: off)

# @nocow            Turn off copy-on-write (valid only on btrfs; default: off)

#

# Since: 2.12

##

{ 'struct': 'BlockdevCreateOptionsFile',

  'data': { 'filename':         'str',

            'size':             'size',

            '*preallocation':   'PreallocMode',

            '*nocow':           'bool' } }



##

# @BlockdevQcow2Version:

#
@@ -3429,7 +3447,7 @@ 
      'bochs':          'BlockdevCreateNotSupported',

      'cloop':          'BlockdevCreateNotSupported',

      'dmg':            'BlockdevCreateNotSupported',

      'file':           'BlockdevCreateNotSupported',

      'file':           'BlockdevCreateOptionsFile',

      'ftp':            'BlockdevCreateNotSupported',

      'ftps':           'BlockdevCreateNotSupported',

      'gluster':        'BlockdevCreateNotSupported',