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[88.21.207.26]) by smtp.gmail.com with ESMTPSA id k6sm12762713wma.19.2020.05.04.02.46.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 May 2020 02:46:57 -0700 (PDT) From: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= To: qemu-devel@nongnu.org Subject: [PATCH 3/6] sysemu/block-backend: Document blk_read()/blk_pwrite() Date: Mon, 4 May 2020 11:46:38 +0200 Message-Id: <20200504094641.4963-4-philmd@redhat.com> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20200504094641.4963-1-philmd@redhat.com> References: <20200504094641.4963-1-philmd@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.120; envelope-from=philmd@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/04 04:24:57 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Fam Zheng , qemu-block@nongnu.org, Maxim Levitsky , Keith Busch , Stefan Hajnoczi , Max Reitz , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The blk_read()/blk_pwrite() return value is not obvious, document it. Signed-off-by: Philippe Mathieu-Daudé --- include/sysemu/block-backend.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index f2dcf63ae3..823b8e94a7 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -153,7 +153,31 @@ BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset, int bytes, BdrvRequestFlags flags, BlockCompletionFunc *cb, void *opaque); int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags); + +/** + * blk_pread: + * + * @blk - the block backend where the buffer content is going to be read from + * @offset: position in bytes to read at + * @buf: the data buffer + * @bytes: number of bytes to read + * + * Returns: the number of bytes read on success, or a negative errno otherwise. + */ int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int bytes); + +/** + * blk_pwrite: + * + * @blk - the block backend where the buffer content is going to be written to + * @offset: position in bytes to write at + * @buf: the data buffer + * @bytes: number of bytes of @buf to write + * @flags: request flags + * + * Returns: the number of bytes consumed on success, + * or a negative errno otherwise. + */ int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int bytes, BdrvRequestFlags flags); int64_t blk_getlength(BlockBackend *blk);