From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48821) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adKaw-0001ST-0i for qemu-devel@nongnu.org; Tue, 08 Mar 2016 11:34:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1adKas-0002ge-1q for qemu-devel@nongnu.org; Tue, 08 Mar 2016 11:34:49 -0500 From: Kevin Wolf Date: Tue, 8 Mar 2016 17:34:23 +0100 Message-Id: <1457454872-12183-3-git-send-email-kwolf@redhat.com> In-Reply-To: <1457454872-12183-1-git-send-email-kwolf@redhat.com> References: <1457454872-12183-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH 02/11] block: Introduce blk_set_allow_write_beyond_eof() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org We check that the guest can't write beyond the end of its disk, but for other internal users it can make sense to allow growing a file. Signed-off-by: Kevin Wolf --- block/block-backend.c | 23 ++++++++++++++++------- include/sysemu/block-backend.h | 1 + 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index ebdf78a..03e71b4 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -50,6 +50,8 @@ struct BlockBackend { bool iostatus_enabled; BlockDeviceIoStatus iostatus; + bool allow_write_beyond_eof; + NotifierList remove_bs_notifiers, insert_bs_notifiers; }; @@ -579,6 +581,11 @@ void blk_iostatus_set_err(BlockBackend *blk, int error) } } +void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow) +{ + blk->allow_write_beyond_eof = allow; +} + static int blk_check_byte_request(BlockBackend *blk, int64_t offset, size_t size) { @@ -592,17 +599,19 @@ static int blk_check_byte_request(BlockBackend *blk, int64_t offset, return -ENOMEDIUM; } - len = blk_getlength(blk); - if (len < 0) { - return len; - } - if (offset < 0) { return -EIO; } - if (offset > len || len - offset < size) { - return -EIO; + if (!blk->allow_write_beyond_eof) { + len = blk_getlength(blk); + if (len < 0) { + return len; + } + + if (offset > len || len - offset < size) { + return -EIO; + } } return 0; diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index 66c5cf2..00d69ba 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -78,6 +78,7 @@ void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs); void blk_hide_on_behalf_of_hmp_drive_del(BlockBackend *blk); +void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow); void blk_iostatus_enable(BlockBackend *blk); bool blk_iostatus_is_enabled(const BlockBackend *blk); BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk); -- 1.8.3.1