From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47130) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yb0PM-00081e-13 for qemu-devel@nongnu.org; Thu, 26 Mar 2015 01:32:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yb0PH-0007Et-MT for qemu-devel@nongnu.org; Thu, 26 Mar 2015 01:32:43 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:41820) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yb0PG-0007DI-V6 for qemu-devel@nongnu.org; Thu, 26 Mar 2015 01:32:39 -0400 From: zhanghailiang Date: Thu, 26 Mar 2015 13:29:14 +0800 Message-ID: <1427347774-8960-9-git-send-email-zhang.zhanghailiang@huawei.com> In-Reply-To: <1427347774-8960-1-git-send-email-zhang.zhanghailiang@huawei.com> References: <1427347774-8960-1-git-send-email-zhang.zhanghailiang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [RFC PATCH v4 08/28] 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, amit.shah@redhat.com, Yang Hongyang , david@gibson.dropbear.id.au 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: Yang Hongyang Signed-off-by: zhanghailiang --- include/migration/qemu-file.h | 3 ++- migration/qemu-file-buf.c | 58 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 60 insertions(+), 1 deletion(-) diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index 745a850..09a0e2a 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -140,7 +140,8 @@ 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, int size); +int qsb_fill_buffer(QEMUSizedBuffer *qsb, QEMUFile *f, int size); /* * For use on files opened with qemu_bufopen diff --git a/migration/qemu-file-buf.c b/migration/qemu-file-buf.c index 16a51a1..686f417 100644 --- a/migration/qemu-file-buf.c +++ b/migration/qemu-file-buf.c @@ -365,6 +365,64 @@ 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, int size) +{ + int i, l; + + 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) + */ +int qsb_fill_buffer(QEMUSizedBuffer *qsb, QEMUFile *f, int size) +{ + ssize_t rc = qsb_grow(qsb, size); + int pending = size, i; + qsb->used = 0; + uint8_t *buf = NULL; + + if (rc < 0) { + return rc; + } + + for (i = 0; i < qsb->n_iov && pending > 0; i++) { + int doneone = 0; + /* read until iov full */ + while (doneone < qsb->iov[i].iov_len && pending > 0) { + int 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; -- 1.7.12.4