From bc6346df8d89ece4814be7dff951ec1a7d259938 Mon Sep 17 00:00:00 2001 From: Martin Mares Date: Tue, 20 Jul 1999 12:13:38 +0000 Subject: [PATCH] Rewrote the pread/pwrite things once again. Use pread and pwrite only when we are certain it's safe (i.e., glibc 2.1 on all architectures or any libc on a i386 where we really know how to use syscalls directly). In all other cases, emulate it with lseek/read/write. --- ChangeLog | 6 +++++ Makefile | 6 ++--- lib/pci.h | 3 ++- lib/proc.c | 69 +++++++++++++++++++++++++++++++++++------------------- 4 files changed, 56 insertions(+), 28 deletions(-) diff --git a/ChangeLog b/ChangeLog index 83fae9b..0bd4151 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ Tue Jul 20 13:25:09 1999 Martin Mares + * lib/proc.c: Rewrote the pread/pwrite things once again. Use pread + and pwrite only when we are certain it's safe (i.e., glibc 2.1 + on all architectures or any libc on a i386 where we really know + how to use syscalls directly). In all other cases, emulate it + with lseek/read/write. + * pci.ids: Some more IDs. Mon Jul 19 14:10:36 1999 Martin Mares diff --git a/Makefile b/Makefile index 6d936e2..f8ad9f1 100644 --- a/Makefile +++ b/Makefile @@ -1,4 +1,4 @@ -# $Id: Makefile,v 1.18 1999/07/07 11:23:03 mj Exp $ +# $Id: Makefile,v 1.19 1999/07/20 12:13:39 mj Exp $ # Makefile for Linux PCI Utilities # (c) 1998--1999 Martin Mares @@ -9,10 +9,10 @@ CFLAGS=$(OPT) -Wall -W -Wno-parentheses -Wstrict-prototypes -Werror ROOT=/ PREFIX=/usr -VERSION=2.1-pre4 +VERSION=2.1-pre5 SUFFIX= #SUFFIX=-alpha -DATE=99-05-19 +DATE=99-07-20 export diff --git a/lib/pci.h b/lib/pci.h index 168d9ad..4fca73e 100644 --- a/lib/pci.h +++ b/lib/pci.h @@ -1,5 +1,5 @@ /* - * $Id: pci.h,v 1.4 1999/07/07 11:23:11 mj Exp $ + * $Id: pci.h,v 1.5 1999/07/20 12:13:40 mj Exp $ * * The PCI Library * @@ -76,6 +76,7 @@ struct pci_access { int fd; /* proc: fd */ int fd_rw; /* proc: fd opened read-write */ struct pci_dev *cached_dev; /* proc: device the fd is for */ + int fd_pos; /* proc: current position */ }; /* Initialize PCI access */ diff --git a/lib/proc.c b/lib/proc.c index 5edc7b0..9f617c3 100644 --- a/lib/proc.c +++ b/lib/proc.c @@ -1,5 +1,5 @@ /* - * $Id: proc.c,v 1.4 1999/07/07 11:23:12 mj Exp $ + * $Id: proc.c,v 1.5 1999/07/20 12:13:42 mj Exp $ * * The PCI Library -- Configuration Access via /proc/bus/pci * @@ -19,40 +19,60 @@ #include "internal.h" -#include -#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 1 -#include -#endif - /* - * As libc doesn't support pread/pwrite yet, we have to call them directly - * or use lseek/read/write instead. + * We'd like to use pread/pwrite for configuration space accesses, but + * unfortunately it isn't simple at all since all libc's until glibc 2.1 + * don't define it. */ -#if !(defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ > 0) -#if defined(__GLIBC__) && !(defined(__powerpc__) && __GLIBC__ == 2 && __GLIBC_MINOR__ == 0) +#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ > 0 +/* glibc 2.1 or newer -> pread/pwrite supported automatically */ + +#elif defined(i386) && defined(__GLIBC__) +/* glibc 2.0 on i386 -> call syscalls directly */ +#include +#include #ifndef SYS_pread #define SYS_pread 180 #endif -static int -pread(unsigned int fd, void *buf, size_t size, loff_t where) -{ - return syscall(SYS_pread, fd, buf, size, where); -} - +static int pread(unsigned int fd, void *buf, size_t size, loff_t where) +{ return syscall(SYS_pread, fd, buf, size, where); } #ifndef SYS_pwrite #define SYS_pwrite 181 #endif -static int -pwrite(unsigned int fd, void *buf, size_t size, loff_t where) -{ - return syscall(SYS_pwrite, fd, buf, size, where); -} -#else +static int pwrite(unsigned int fd, void *buf, size_t size, loff_t where) +{ return syscall(SYS_pwrite, fd, buf, size, where); } + +#elif defined(i386) +/* old libc on i386 -> call syscalls directly the old way */ +#include static _syscall4(int, pread, unsigned int, fd, void *, buf, size_t, size, loff_t, where); static _syscall4(int, pwrite, unsigned int, fd, void *, buf, size_t, size, loff_t, where); + +#else +/* In all other cases we use lseek/read/write instead to be safe */ +#define make_rw_glue(op) \ + static int do_##op(struct pci_dev *d, int fd, void *buf, size_t size, loff_t where) \ + { \ + struct pci_access *a = d->access; \ + int r; \ + if (a->fd_pos != where && lseek(fd, where, SEEK_SET) < 0) \ + return -1; \ + r = op(fd, buf, size); \ + if (r < 0) \ + a->fd_pos = -1; \ + else \ + a->fd_pos = where + r; \ + return r; \ + } +make_rw_glue(read) +make_rw_glue(write) +#define HAVE_DO_READ #endif +#ifndef HAVE_DO_READ +#define do_read(d,f,b,l,p) pread(f,b,l,p) +#define do_write(d,f,b,l,p) pwrite(f,b,l,p) #endif static void @@ -170,6 +190,7 @@ proc_setup(struct pci_dev *d, int rw) if (a->fd < 0) a->warning("Cannot open %s", buf); a->cached_dev = d; + a->fd_pos = 0; } return a->fd; } @@ -182,7 +203,7 @@ proc_read(struct pci_dev *d, int pos, byte *buf, int len) if (fd < 0) return 0; - res = pread(fd, buf, len, pos); + res = do_read(d, fd, buf, len, pos); if (res < 0) { d->access->warning("proc_read: read failed: %s", strerror(errno)); @@ -204,7 +225,7 @@ proc_write(struct pci_dev *d, int pos, byte *buf, int len) if (fd < 0) return 0; - res = pwrite(fd, buf, len, pos); + res = do_write(d, fd, buf, len, pos); if (res < 0) { d->access->warning("proc_write: write failed: %s", strerror(errno)); -- 2.39.2