diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2014-05-20 11:57:52 +0100 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2014-05-20 11:57:52 +0100 |
commit | ca8c0fab9504f000216308cafc833eb957fe9284 (patch) | |
tree | 5ee125a6112ff816903ac08f2c0de6d62c987061 /util | |
parent | c5fa6c86d0765f837515d1c10654c621724a77e0 (diff) | |
parent | 465bee1da82e43f18d10c43cc7566d0284ad13a9 (diff) |
Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block patches
# gpg: Signature made Mon 19 May 2014 15:21:14 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream: (22 commits)
block: optimize zero writes with bdrv_write_zeroes
blockdev: add a function to parse enum ids from strings
util: add qemu_iovec_is_zero
qcow1: Stricter backing file length check
qcow1: Validate image size (CVE-2014-0223)
qcow1: Validate L2 table size (CVE-2014-0222)
qcow1: Check maximum cluster size
qcow1: Make padding in the header explicit
curl: Add usage documentation
curl: Add sslverify option
curl: Remove broken parsing of options from url
curl: Fix build when curl_multi_socket_action isn't available
qemu-iotests: Fix blkdebug in VM drive in 030
qemu-iotests: Fix core dump suppression in test 039
iotests: Add test for the JSON protocol
block: Allow JSON filenames
check-qdict: Add test for qdict_join()
qdict: Add qdict_join()
block: add test for vhdx image created by Disk2VHD
block: vhdx - account for identical header sections
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'util')
-rw-r--r-- | util/iov.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/util/iov.c b/util/iov.c index 6569b5aae1..49f88388f8 100644 --- a/util/iov.c +++ b/util/iov.c @@ -335,6 +335,27 @@ void qemu_iovec_concat(QEMUIOVector *dst, qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes); } +/* + * Check if the contents of the iovecs are all zero + */ +bool qemu_iovec_is_zero(QEMUIOVector *qiov) +{ + int i; + for (i = 0; i < qiov->niov; i++) { + size_t offs = QEMU_ALIGN_DOWN(qiov->iov[i].iov_len, 4 * sizeof(long)); + uint8_t *ptr = qiov->iov[i].iov_base; + if (offs && !buffer_is_zero(qiov->iov[i].iov_base, offs)) { + return false; + } + for (; offs < qiov->iov[i].iov_len; offs++) { + if (ptr[offs]) { + return false; + } + } + } + return true; +} + void qemu_iovec_destroy(QEMUIOVector *qiov) { assert(qiov->nalloc != -1); |