1 /* 2 * $Id: proc.c,v 1.5 1999/07/20 12:13:42 mj Exp $ 3 * 4 * The PCI Library -- Configuration Access via /proc/bus/pci 5 * 6 * Copyright (c) 1997--1999 Martin Mares <[email protected]> 7 * 8 * Can be freely distributed and used under the terms of the GNU GPL. 9 */ 10 11 #define _GNU_SOURCE 12 13 #include <stdio.h> 14 #include <string.h> 15 #include <unistd.h> 16 #include <errno.h> 17 #include <fcntl.h> 18 #include <sys/types.h> 19 20 #include "internal.h" 21 22 /* 23 * We'd like to use pread/pwrite for configuration space accesses, but 24 * unfortunately it isn't simple at all since all libc's until glibc 2.1 25 * don't define it. 26 */ 27 28 #if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ > 0 29 /* glibc 2.1 or newer -> pread/pwrite supported automatically */ 30 31 #elif defined(i386) && defined(__GLIBC__) 32 /* glibc 2.0 on i386 -> call syscalls directly */ 33 #include <asm/unistd.h> 34 #include <syscall-list.h> 35 #ifndef SYS_pread 36 #define SYS_pread 180 37 #endif 38 static int pread(unsigned int fd, void *buf, size_t size, loff_t where) 39 { return syscall(SYS_pread, fd, buf, size, where); } 40 #ifndef SYS_pwrite 41 #define SYS_pwrite 181 42 #endif 43 static int pwrite(unsigned int fd, void *buf, size_t size, loff_t where) 44 { return syscall(SYS_pwrite, fd, buf, size, where); } 45 46 #elif defined(i386) 47 /* old libc on i386 -> call syscalls directly the old way */ 48 #include <asm/unistd.h> 49 static _syscall4(int, pread, unsigned int, fd, void *, buf, size_t, size, loff_t, where); 50 static _syscall4(int, pwrite, unsigned int, fd, void *, buf, size_t, size, loff_t, where); 51 52 #else 53 /* In all other cases we use lseek/read/write instead to be safe */ 54 #define make_rw_glue(op) \ 55 static int do_##op(struct pci_dev *d, int fd, void *buf, size_t size, loff_t where) \ 56 { \ 57 struct pci_access *a = d->access; \ 58 int r; \ 59 if (a->fd_pos != where && lseek(fd, where, SEEK_SET) < 0) \ 60 return -1; \ 61 r = op(fd, buf, size); \ 62 if (r < 0) \ 63 a->fd_pos = -1; \ 64 else \ 65 a->fd_pos = where + r; \ 66 return r; \ 67 } 68 make_rw_glue(read) 69 make_rw_glue(write) 70 #define HAVE_DO_READ 71 #endif 72 73 #ifndef HAVE_DO_READ 74 #define do_read(d,f,b,l,p) pread(f,b,l,p) 75 #define do_write(d,f,b,l,p) pwrite(f,b,l,p) 76 #endif 77 78 static void 79 proc_config(struct pci_access *a) 80 { 81 a->method_params[PCI_ACCESS_PROC_BUS_PCI] = PATH_PROC_BUS_PCI; 82 } 83 84 static int 85 proc_detect(struct pci_access *a) 86 { 87 char *name = a->method_params[PCI_ACCESS_PROC_BUS_PCI]; 88 89 if (access(name, R_OK)) 90 { 91 a->warning("Cannot open %s", name); 92 return 0; 93 } 94 a->debug("...using %s", name); 95 return 1; 96 } 97 98 static void 99 proc_init(struct pci_access *a) 100 { 101 a->fd = -1; 102 } 103 104 static void 105 proc_cleanup(struct pci_access *a) 106 { 107 if (a->fd >= 0) 108 { 109 close(a->fd); 110 a->fd = -1; 111 } 112 } 113 114 static void 115 proc_scan(struct pci_access *a) 116 { 117 FILE *f; 118 char buf[256]; 119 120 if (snprintf(buf, sizeof(buf), "%s/devices", a->method_params[PCI_ACCESS_PROC_BUS_PCI]) == sizeof(buf)) 121 a->error("File name too long"); 122 f = fopen(buf, "r"); 123 if (!f) 124 a->error("Cannot open %s", buf); 125 while (fgets(buf, sizeof(buf)-1, f)) 126 { 127 struct pci_dev *d = pci_alloc_dev(a); 128 unsigned int dfn, vend, cnt, known; 129 130 cnt = sscanf(buf, 131 #ifdef HAVE_LONG_ADDRESS 132 "%x %x %x %llx %llx %llx %llx %llx %llx %llx %llx %llx %llx %llx %llx %llx %llx", 133 #else 134 "%x %x %x %lx %lx %lx %lx %lx %lx %lx %lx %lx %lx %lx %lx %lx %lx", 135 #endif 136 &dfn, 137 &vend, 138 &d->irq, 139 &d->base_addr[0], 140 &d->base_addr[1], 141 &d->base_addr[2], 142 &d->base_addr[3], 143 &d->base_addr[4], 144 &d->base_addr[5], 145 &d->rom_base_addr, 146 &d->size[0], 147 &d->size[1], 148 &d->size[2], 149 &d->size[3], 150 &d->size[4], 151 &d->size[5], 152 &d->rom_size); 153 if (cnt != 9 && cnt != 10 && cnt != 17) 154 a->error("proc: parse error (read only %d items)", cnt); 155 d->bus = dfn >> 8U; 156 d->dev = PCI_SLOT(dfn & 0xff); 157 d->func = PCI_FUNC(dfn & 0xff); 158 d->vendor_id = vend >> 16U; 159 d->device_id = vend & 0xffff; 160 known = PCI_FILL_IDENT; 161 if (!a->buscentric) 162 { 163 known |= PCI_FILL_IRQ | PCI_FILL_BASES; 164 if (cnt >= 10) 165 known |= PCI_FILL_ROM_BASE; 166 if (cnt >= 17) 167 known |= PCI_FILL_SIZES; 168 } 169 d->known_fields = known; 170 pci_link_dev(a, d); 171 } 172 fclose(f); 173 } 174 175 static int 176 proc_setup(struct pci_dev *d, int rw) 177 { 178 struct pci_access *a = d->access; 179 180 if (a->cached_dev != d || a->fd_rw < rw) 181 { 182 char buf[256]; 183 if (a->fd >= 0) 184 close(a->fd); 185 if (snprintf(buf, sizeof(buf), "%s/%02x/%02x.%d", a->method_params[PCI_ACCESS_PROC_BUS_PCI], 186 d->bus, d->dev, d->func) == sizeof(buf)) 187 a->error("File name too long"); 188 a->fd_rw = a->writeable || rw; 189 a->fd = open(buf, a->fd_rw ? O_RDWR : O_RDONLY); 190 if (a->fd < 0) 191 a->warning("Cannot open %s", buf); 192 a->cached_dev = d; 193 a->fd_pos = 0; 194 } 195 return a->fd; 196 } 197 198 static int 199 proc_read(struct pci_dev *d, int pos, byte *buf, int len) 200 { 201 int fd = proc_setup(d, 0); 202 int res; 203 204 if (fd < 0) 205 return 0; 206 res = do_read(d, fd, buf, len, pos); 207 if (res < 0) 208 { 209 d->access->warning("proc_read: read failed: %s", strerror(errno)); 210 return 0; 211 } 212 else if (res != len) 213 { 214 d->access->warning("proc_read: tried to read %d bytes at %d, but got only %d", len, pos, res); 215 return 0; 216 } 217 return 1; 218 } 219 220 static int 221 proc_write(struct pci_dev *d, int pos, byte *buf, int len) 222 { 223 int fd = proc_setup(d, 1); 224 int res; 225 226 if (fd < 0) 227 return 0; 228 res = do_write(d, fd, buf, len, pos); 229 if (res < 0) 230 { 231 d->access->warning("proc_write: write failed: %s", strerror(errno)); 232 return 0; 233 } 234 else if (res != len) 235 { 236 d->access->warning("proc_write: tried to write %d bytes at %d, but got only %d", len, pos, res); 237 return 0; 238 } 239 return 1; 240 } 241 242 static void 243 proc_cleanup_dev(struct pci_dev *d) 244 { 245 if (d->access->cached_dev == d) 246 d->access->cached_dev = NULL; 247 } 248 249 struct pci_methods pm_linux_proc = { 250 "/proc/bus/pci", 251 proc_config, 252 proc_detect, 253 proc_init, 254 proc_cleanup, 255 proc_scan, 256 pci_generic_fill_info, 257 proc_read, 258 proc_write, 259 NULL, /* init_dev */ 260 proc_cleanup_dev 261 }; 262