Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752377AbWCFLD0 (ORCPT ); Mon, 6 Mar 2006 06:03:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750834AbWCFLDZ (ORCPT ); Mon, 6 Mar 2006 06:03:25 -0500 Received: from mail-in-02.arcor-online.net ([151.189.21.42]:22731 "EHLO mail-in-02.arcor-online.net") by vger.kernel.org with ESMTP id S1750730AbWCFLDZ (ORCPT ); Mon, 6 Mar 2006 06:03:25 -0500 Date: Mon, 6 Mar 2006 12:03:17 +0100 (CET) From: Bodo Eggert <7eggert@gmx.de> To: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: RFC: Move SG_GET_SCSI_ID from sg to scsi Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@web.de Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6556 Lines: 160 I suggest moving the SG_GET_SCSI_ID ioctl from sg to scsi, since it's generally usefull and the alternative function SCSI_IOCTL_GET_IDLUN is limited in range (in-kernel data types may be larger) and functionality (type, ...). However, I have some questions about that ioctl: - There is the concept of 8-Byte-LUNs: Are they mapped to integer LUNs? Should the extra space in the struct sg_scsi_id be used for that? Or should I abandon the idea and create a new IOCTL instead? - The original IOCTL will check for sdp->detached. If the moved-to-scsi ioctl is called, the check will be done before chaining from sg, but what will I need to check if it's called on a non-sg device? - Are there any (planned) changes that will conflict with this patch? Proof-of-concept-hack (unclean): diff -pru -x dontdiff 2.6.15.ori/drivers/scsi/scsi_ioctl.c 2.6.15/drivers/scsi/scsi_ioctl.c --- 2.6.15.ori/drivers/scsi/scsi_ioctl.c 2006-02-08 15:10:48.000000000 +0100 +++ 2.6.15/drivers/scsi/scsi_ioctl.c 2006-03-04 21:24:13.000000000 +0100 @@ -434,6 +434,31 @@ int scsi_ioctl(struct scsi_device *sdev, START_STOP_TIMEOUT, NORMAL_RETRIES); case SCSI_IOCTL_GET_PCI: return scsi_ioctl_get_pci(sdev, arg); + case SG_GET_SCSI_ID: + if (!access_ok(VERIFY_WRITE, arg, sizeof (sg_scsi_id_t))) + return -EFAULT; + else { + sg_scsi_id_t __user *sg_idp = arg; + +// if (sdp->detached) +// return -ENODEV; +// is the above covered by !sdev ath the +// beginning of this function? + __put_user((int) sdev->host->host_no, + &sg_idp->host_no); + __put_user((int) sdev->channel, + &sg_idp->channel); + __put_user((int) sdev->id, &sg_idp->scsi_id); + __put_user((int) sdev->lun, &sg_idp->lun); + __put_user((int) sdev->type, &sg_idp->scsi_type); + __put_user((short) sdev->host->cmd_per_lun, + &sg_idp->h_cmd_per_lun); + __put_user((short) sdev->queue_depth, + &sg_idp->d_queue_depth); + __put_user(0, &sg_idp->unused[0]); + __put_user(0, &sg_idp->unused[1]); + return 0; + } default: if (sdev->host->hostt->ioctl) return sdev->host->hostt->ioctl(sdev, cmd, arg); diff -pru -x dontdiff 2.6.15.ori/drivers/scsi/sg.c 2.6.15/drivers/scsi/sg.c --- 2.6.15.ori/drivers/scsi/sg.c 2006-02-08 15:10:48.000000000 +0100 +++ 2.6.15/drivers/scsi/sg.c 2006-03-04 22:15:15.000000000 +0100 @@ -871,29 +871,6 @@ sg_ioctl(struct inode *inode, struct fil return 0; case SG_GET_LOW_DMA: return put_user((int) sfp->low_dma, ip); - case SG_GET_SCSI_ID: - if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t))) - return -EFAULT; - else { - sg_scsi_id_t __user *sg_idp = p; - - if (sdp->detached) - return -ENODEV; - __put_user((int) sdp->device->host->host_no, - &sg_idp->host_no); - __put_user((int) sdp->device->channel, - &sg_idp->channel); - __put_user((int) sdp->device->id, &sg_idp->scsi_id); - __put_user((int) sdp->device->lun, &sg_idp->lun); - __put_user((int) sdp->device->type, &sg_idp->scsi_type); - __put_user((short) sdp->device->host->cmd_per_lun, - &sg_idp->h_cmd_per_lun); - __put_user((short) sdp->device->queue_depth, - &sg_idp->d_queue_depth); - __put_user(0, &sg_idp->unused[0]); - __put_user(0, &sg_idp->unused[1]); - return 0; - } case SG_SET_FORCE_PACK_ID: result = get_user(val, ip); if (result) @@ -1072,6 +1049,7 @@ sg_ioctl(struct inode *inode, struct fil case SCSI_IOCTL_GET_BUS_NUMBER: case SCSI_IOCTL_PROBE_HOST: case SG_GET_TRANSFORM: + case SG_GET_SCSI_ID: if (sdp->detached) return -ENODEV; return scsi_ioctl(sdp->device, cmd_in, p); diff -pru -x dontdiff 2.6.15.ori/include/scsi/scsi.h 2.6.15/include/scsi/scsi.h --- 2.6.15.ori/include/scsi/scsi.h 2006-02-08 15:11:08.000000000 +0100 +++ 2.6.15/include/scsi/scsi.h 2006-03-04 11:11:31.000000000 +0100 @@ -245,6 +245,21 @@ struct scsi_lun { __u8 scsi_lun[8]; }; +// copyed to scsi.h, so don't typedef it twice: +#ifndef sg_scsi_id_t +typedef struct sg_scsi_id { /* used by SG_GET_SCSI_ID ioctl() */ + int host_no; /* as in "scsi" where 'n' is one of 0, 1, 2 etc */ + int channel; + int scsi_id; /* scsi id of target device */ + int lun; + int scsi_type; /* TYPE_... defined in scsi/scsi.h */ + short h_cmd_per_lun;/* host (adapter) maximum commands per lun */ + short d_queue_depth;/* device (or adapter) maximum queue length */ + int unused[2]; /* probably find a good use, set 0 for now */ +} sg_scsi_id_t; /* 32 bytes long on i386 */ +#define sg_scsi_id_t sg_scsi_id_t +#endif + /* * MESSAGE CODES */ diff -pru -x dontdiff 2.6.15.ori/include/scsi/sg.h 2.6.15/include/scsi/sg.h --- 2.6.15.ori/include/scsi/sg.h 2005-06-17 21:48:29.000000000 +0200 +++ 2.6.15/include/scsi/sg.h 2006-03-04 11:11:30.000000000 +0100 @@ -156,6 +156,8 @@ typedef struct sg_io_hdr #define SG_INFO_MIXED_IO 0x4 /* part direct, part indirect IO */ +// copyed to scsi.h, so don't typedef it twice: +#ifndef sg_scsi_id_t typedef struct sg_scsi_id { /* used by SG_GET_SCSI_ID ioctl() */ int host_no; /* as in "scsi" where 'n' is one of 0, 1, 2 etc */ int channel; @@ -166,6 +168,8 @@ typedef struct sg_scsi_id { /* used by S short d_queue_depth;/* device (or adapter) maximum queue length */ int unused[2]; /* probably find a good use, set 0 for now */ } sg_scsi_id_t; /* 32 bytes long on i386 */ +#define sg_scsi_id_t sg_scsi_id_t +#endif typedef struct sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */ char req_state; /* 0 -> not used, 1 -> written, 2 -> ready to read */ @@ -196,8 +200,11 @@ typedef struct sg_req_info { /* used by #define SG_GET_RESERVED_SIZE 0x2272 /* actual size of reserved buffer */ /* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */ +#ifndef SG_GET_SCSI_ID #define SG_GET_SCSI_ID 0x2276 /* Yields fd's bus, chan, dev, lun + type */ -/* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */ +#endif +/* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN, * + * but that is limited in range (/usurally/ no problem ...) */ /* Override host setting and always DMA using low memory ( <16MB on i386) */ #define SG_SET_FORCE_LOW_DMA 0x2279 /* 0-> use adapter setting, 1-> force */ - 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/