Comments? (A version with debug code included is here: http://volker.dnsalias.net/soft/patch/kernel-2.6.13-sg-io32-debug.diff ) Purpose of this patch: establish binary compatibility with 32 bit x86 code on AMD64 64 bit kernels, in the use of struct sg_io_hdr via write()/read() calls. Currently this binary compatibility only exists with ioctl(). 32bit applications which use or are linked with sanei_scsi.c of the SANE project (sane-project.org) need this patch. Tested: on AMD64, SUSE Linux 10.0 kernel, with a commercial 32 bit scanning application xsane 64 bit cdrecord 64 bit Thanks are due to: Abel Deuring, Henning Meier-Geinitz, Dieter Jurzitza - all sane-devel mailing list. TODO: how many other 32/64 bit architectures does this apply to? Signed-off-by: Volker Kuhlmann <VolkerKuhlmann.gmx.de> 13 Jan 2006 --- drivers/scsi/sg.c.orig 2005-11-30 09:35:27.000000000 +1300 +++ drivers/scsi/sg.c 2006-01-14 10:30:54.000000000 +1300 @@ -11,6 +11,9 @@ * * Modified 19-JAN-1998 Richard Gooch <rgooch@xxxxxxxxxxxxx> Devfs support * + * Modified 14 Jan 2006 Volker Kuhlmann <coding,top.geek.nz> + * - 32 bit binary compatibility on AMD64 for read()/write() sg_io_hdr. + * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) @@ -18,8 +21,8 @@ * */ -static int sg_version_num = 30533; /* 2 digits for each component */ -#define SG_VERSION_STR "3.5.33" +static int sg_version_num = 30534; /* 2 digits for each component */ +#define SG_VERSION_STR "3.5.34" /* * D. P. Gilbert (dgilbert@xxxxxxxxxxxx, dougg@xxxxxxxxxxxxx), notes: @@ -49,6 +52,7 @@ #include <linux/seq_file.h> #include <linux/blkdev.h> #include <linux/delay.h> +#include <linux/compat.h> #include "scsi.h" #include <scsi/scsi_dbg.h> @@ -61,7 +65,7 @@ #ifdef CONFIG_SCSI_PROC_FS #include <linux/proc_fs.h> -static char *sg_version_date = "20050328"; +static char *sg_version_date = "20060114"; static int sg_proc_init(void); static void sg_proc_cleanup(void); @@ -176,6 +180,41 @@ struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */ } Sg_device; +/* Replication of struct sg_io_hdr from scsi/sg.h, but with the memory layout + of a x86 32 bit architecture, even when compiled on AMD64 64 bit. + THIS MUST ALWAYS MATCH a (32 bit architecture) struct sg_io_hdr!!! +*/ +typedef struct sg_io_hdr32 +{ + int interface_id; /* [i] 'S' for SCSI generic (required) */ + int dxfer_direction; /* [i] data transfer direction */ + unsigned char cmd_len; /* [i] SCSI command length ( <= 16 bytes) */ + unsigned char mx_sb_len; /* [i] max length to write to sbp */ + unsigned short iovec_count; /* [i] 0 implies no scatter gather */ + unsigned int dxfer_len; /* [i] byte count of data transfer */ + // 16 bytes + signed int dxferp; /* pointers are only 4 bytes */ + signed int cmdp; /* " */ + signed int sbp; /* " */ + // 12 bytes + unsigned int timeout; /* [i] MAX_UINT->no timeout (unit: millisec) */ + unsigned int flags; /* [i] 0 -> default, see SG_FLAG... */ + int pack_id; /* [i->o] unused internally (normally) */ + // 12 bytes + signed int usr_ptr; /* pointers are only 4 bytes */ + // 4 bytes + unsigned char status; /* [o] scsi status */ + unsigned char masked_status;/* [o] shifted, masked scsi status */ + unsigned char msg_status; /* [o] messaging level data (optional) */ + unsigned char sb_len_wr; /* [o] byte count actually written to sbp */ + unsigned short host_status; /* [o] errors from host adapter */ + unsigned short driver_status;/* [o] errors from software driver */ + int resid; /* [o] dxfer_len - actual_transferred */ + unsigned int duration; /* [o] time taken by cmd (unit: millisec) */ + unsigned int info; /* [o] auxiliary information */ + // 20 bytes +} sg_io_hdr32_t; /* 64 bytes long (on x86_64!) */ + static int sg_fasync(int fd, struct file *filp, int mode); static void sg_cmd_done(Scsi_Cmnd * SCpnt); /* tasklet or soft irq callback */ static int sg_start_req(Sg_request * srp); @@ -214,6 +253,8 @@ #ifdef CONFIG_SCSI_PROC_FS static int sg_last_dev(void); #endif +static inline void copy_hdr32_64 (sg_io_hdr_t * new, sg_io_hdr32_t * hdr); +static inline void copy_64_hdr32 (sg_io_hdr32_t * new, sg_io_hdr_t * hdr); static Sg_device **sg_dev_arr = NULL; static int sg_dev_max; @@ -221,6 +262,7 @@ #define SZ_SG_HEADER sizeof(struct sg_header) #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t) +#define SZ_SG_IO32_HDR sizeof(sg_io_hdr32_t) #define SZ_SG_IOVEC sizeof(sg_iovec_t) #define SZ_SG_REQ_INFO sizeof(sg_req_info_t) @@ -480,6 +522,32 @@ return retval; } +/* Copy a sg_io_hdr32_t (32 bit) to a sg_io_hdr_t (64 bit layout). + This must always match struct sg_io_hdr! */ +static inline void +copy_hdr32_64 (sg_io_hdr_t * new, sg_io_hdr32_t * hdr) { + /* memcpy(new, hdr, 16); already copied when this function is called */ + new->dxferp = compat_ptr(hdr->dxferp); + new->cmdp = compat_ptr(hdr->cmdp); + new->sbp = compat_ptr(hdr->sbp); + memcpy(&(new->timeout), &(hdr->timeout), 12); + new->usr_ptr = compat_ptr(hdr->usr_ptr); + memcpy(&(new->status), &(hdr->status), 20); +} + +/* Copy a sg_io_hdr_t (64 bit layout) to a sg_io_hdr32_t (32 bit). + This must always match struct sg_io_hdr! */ +static inline void +copy_64_hdr32 (sg_io_hdr32_t * new, sg_io_hdr_t * hdr) { + /* memcpy(new, hdr, 16); already copied when this function is called */ + new->dxferp = ptr_to_compat(hdr->dxferp); + new->cmdp = ptr_to_compat(hdr->cmdp); + new->sbp = ptr_to_compat(hdr->sbp); + memcpy(&(new->timeout), &(hdr->timeout), 12); + new->usr_ptr = ptr_to_compat(hdr->usr_ptr); + memcpy(&(new->status), &(hdr->status), 20); +} + static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) { @@ -487,7 +555,7 @@ int err = 0; int len; - if (count < SZ_SG_IO_HDR) { + if (count < SZ_SG_IO_HDR && count != SZ_SG_IO32_HDR) { err = -EINVAL; goto err_out; } @@ -508,9 +576,17 @@ } if (hp->masked_status || hp->host_status || hp->driver_status) hp->info |= SG_INFO_CHECK; - if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) { - err = -EFAULT; - goto err_out; + if (count == SZ_SG_IO_HDR) { + if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) { + err = -EFAULT; + goto err_out; + } + } else { + if (copy_to_user(buf, hp, 16)) {/* copy 4 bytes for error checking */ + err = -EFAULT; + goto err_out; + } + copy_64_hdr32((sg_io_hdr32_t *) buf, hp); } err = sg_read_xfer(srp); err_out: @@ -632,7 +708,7 @@ int timeout; unsigned long ul_timeout; - if (count < SZ_SG_IO_HDR) + if (count < SZ_SG_IO_HDR && count != SZ_SG_IO32_HDR) return -EINVAL; if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; /* protects following copy_from_user()s + get_user()s */ @@ -643,9 +719,17 @@ return -EDOM; } hp = &srp->header; - if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) { - sg_remove_request(sfp, srp); - return -EFAULT; + if (count == SZ_SG_IO_HDR) { + if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) { + sg_remove_request(sfp, srp); + return -EFAULT; + } + } else { + if (__copy_from_user(hp, buf, 16)) {/* copy 4 bytes for error checking */ + sg_remove_request(sfp, srp); + return -EFAULT; + } + copy_hdr32_64(hp, (sg_io_hdr32_t *) buf); } if (hp->interface_id != 'S') { sg_remove_request(sfp, srp); -- Volker Kuhlmann is possibly list0570 with the domain in header http://volker.dnsalias.net/ Please do not CC list postings to me. - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
