Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754356Ab2HaPsl (ORCPT ); Fri, 31 Aug 2012 11:48:41 -0400 Received: from [66.192.166.38] ([66.192.166.38]:55473 "EHLO hancock.steeleye.com" rhost-flags-FAIL-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754264Ab2HaPsk (ORCPT ); Fri, 31 Aug 2012 11:48:40 -0400 Date: Fri, 31 Aug 2012 11:48:40 -0400 From: paul.clements@steeleye.com To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCHv2 1/2] nbd: add set flags ioctl Message-ID: <5040dcd8.o0gAcQjaJ9EalhQI%paul.clements@steeleye.com> User-Agent: nail 11.25 7/29/05 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2907 Lines: 84 Description: This patch adds a set-flags ioctl, allowing various option flags to be set on an nbd device. This allows the nbd-client to set the device flags (to enable read-only mode, or enable discard support, etc.). Flags are typically specified by the nbd-server. During the negotiation phase of the nbd connection, the server sends its flags to the client. The client then uses NBD_SET_FLAGS to inform the kernel of the options. Also included is a one-line fix to debug output for the set-timeout ioctl. Signed-off-by: Paul Clements --- diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index d07c9f7..c544bb4 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -78,6 +78,8 @@ static const char *ioctl_cmd_to_ascii(int cmd) case NBD_SET_SOCK: return "set-sock"; case NBD_SET_BLKSIZE: return "set-blksize"; case NBD_SET_SIZE: return "set-size"; + case NBD_SET_TIMEOUT: return "set-timeout"; + case NBD_SET_FLAGS: return "set-flags"; case NBD_DO_IT: return "do-it"; case NBD_CLEAR_SOCK: return "clear-sock"; case NBD_CLEAR_QUE: return "clear-que"; @@ -460,7 +462,7 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *req) nbd_cmd(req) = NBD_CMD_READ; if (rq_data_dir(req) == WRITE) { nbd_cmd(req) = NBD_CMD_WRITE; - if (nbd->flags & NBD_READ_ONLY) { + if (nbd->flags & NBD_FLAG_READ_ONLY) { dev_err(disk_to_dev(nbd->disk), "Write on read-only\n"); goto error_out; @@ -642,6 +644,10 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, nbd->xmit_timeout = arg * HZ; return 0; + case NBD_SET_FLAGS: + nbd->flags = arg; + return 0; + case NBD_SET_SIZE_BLOCKS: nbd->bytesize = ((u64) arg) * nbd->blksize; bdev->bd_inode->i_size = nbd->bytesize; diff --git a/include/linux/nbd.h b/include/linux/nbd.h index d146ca1..bb349be 100644 --- a/include/linux/nbd.h +++ b/include/linux/nbd.h @@ -27,6 +27,7 @@ #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) #define NBD_DISCONNECT _IO( 0xab, 8 ) #define NBD_SET_TIMEOUT _IO( 0xab, 9 ) +#define NBD_SET_FLAGS _IO( 0xab, 10) enum { NBD_CMD_READ = 0, @@ -34,6 +35,10 @@ enum { NBD_CMD_DISC = 2 }; +/* values for flags field */ +#define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */ +#define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */ + #define nbd_cmd(req) ((req)->cmd[0]) /* userspace doesn't need the nbd_device structure */ @@ -42,10 +47,6 @@ enum { #include #include -/* values for flags field */ -#define NBD_READ_ONLY 0x0001 -#define NBD_WRITE_NOCHK 0x0002 - struct request; struct nbd_device { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/