From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53781) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a19w0-0007Cf-1O for qemu-devel@nongnu.org; Tue, 24 Nov 2015 04:30:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a19vy-00088X-06 for qemu-devel@nongnu.org; Tue, 24 Nov 2015 04:30:47 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:40507) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a19vw-00087P-KM for qemu-devel@nongnu.org; Tue, 24 Nov 2015 04:30:45 -0500 From: zhanghailiang Date: Tue, 24 Nov 2015 17:25:22 +0800 Message-ID: <1448357149-17572-13-git-send-email-zhang.zhanghailiang@huawei.com> In-Reply-To: <1448357149-17572-1-git-send-email-zhang.zhanghailiang@huawei.com> References: <1448357149-17572-1-git-send-email-zhang.zhanghailiang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH COLO-Frame v11 12/39] QEMUSizedBuffer: Introduce two help functions for qsb List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: lizhijian@cn.fujitsu.com, quintela@redhat.com, yunhong.jiang@intel.com, eddie.dong@intel.com, peter.huangpeng@huawei.com, dgilbert@redhat.com, zhanghailiang , arei.gonglei@huawei.com, stefanha@redhat.com, amit.shah@redhat.com, hongyang.yang@easystack.cn Introduce two new QEMUSizedBuffer APIs which will be used by COLO to buffer VM state: One is qsb_put_buffer(), which put the content of a given QEMUSizedBuffer into QEMUFile, this is used to send buffered VM state to secondary. Another is qsb_fill_buffer(), read 'size' bytes of data from the file into qsb, this is used to get VM state from socket into a buffer. Signed-off-by: zhanghailiang Signed-off-by: Li Zhijian Reviewed-by: Dr. David Alan Gilbert --- v11: - size_t'ify these two help functions (Dave's suggestion) --- include/migration/qemu-file.h | 3 ++- migration/qemu-file-buf.c | 61 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+), 1 deletion(-) diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index b5d08d2..ca6a582 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -150,7 +150,8 @@ ssize_t qsb_get_buffer(const QEMUSizedBuffer *, off_t start, size_t count, uint8_t *buf); ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *buf, off_t pos, size_t count); - +void qsb_put_buffer(QEMUFile *f, QEMUSizedBuffer *qsb, size_t size); +size_t qsb_fill_buffer(QEMUSizedBuffer *qsb, QEMUFile *f, size_t size); /* * For use on files opened with qemu_bufopen diff --git a/migration/qemu-file-buf.c b/migration/qemu-file-buf.c index 49516b8..c50a495 100644 --- a/migration/qemu-file-buf.c +++ b/migration/qemu-file-buf.c @@ -366,6 +366,67 @@ ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *source, return count; } +/** + * Put the content of a given QEMUSizedBuffer into QEMUFile. + * + * @f: A QEMUFile + * @qsb: A QEMUSizedBuffer + * @size: size of content to write + */ +void qsb_put_buffer(QEMUFile *f, QEMUSizedBuffer *qsb, size_t size) +{ + size_t l; + int i; + + for (i = 0; i < qsb->n_iov && size > 0; i++) { + l = MIN(qsb->iov[i].iov_len, size); + qemu_put_buffer(f, qsb->iov[i].iov_base, l); + size -= l; + } +} + +/* + * Read 'size' bytes of data from the file into qsb. + * always fill from pos 0 and used after qsb_create(). + * + * It will return size bytes unless there was an error, in which case it will + * return as many as it managed to read (assuming blocking fd's which + * all current QEMUFile are) + */ +size_t qsb_fill_buffer(QEMUSizedBuffer *qsb, QEMUFile *f, size_t size) +{ + ssize_t rc = qsb_grow(qsb, size); + ssize_t pending = size; + int i; + uint8_t *buf = NULL; + + qsb->used = 0; + + if (rc < 0) { + return rc; + } + + for (i = 0; i < qsb->n_iov && pending > 0; i++) { + size_t doneone = 0; + /* read until iov full */ + while (doneone < qsb->iov[i].iov_len && pending > 0) { + size_t readone = 0; + + buf = qsb->iov[i].iov_base; + readone = qemu_get_buffer(f, buf, + MIN(qsb->iov[i].iov_len - doneone, pending)); + if (readone == 0) { + return qsb->used; + } + buf += readone; + doneone += readone; + pending -= readone; + qsb->used += readone; + } + } + return qsb->used; +} + typedef struct QEMUBuffer { QEMUSizedBuffer *qsb; QEMUFile *file; -- 1.8.3.1