diff options
Diffstat (limited to 'lib/proc.c')
| -rw-r--r-- | lib/proc.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/lib/proc.c b/lib/proc.c new file mode 100644 index 0000000..429cea6 --- /dev/null +++ b/lib/proc.c @@ -0,0 +1,230 @@ +/* + * The PCI Library -- Configuration Access via /proc/bus/pci + * + * Copyright (c) 1997--2023 Martin Mares <mj@ucw.cz> + * + * Can be freely distributed and used under the terms of the GNU GPL v2+. + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#define _GNU_SOURCE + +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <sys/types.h> + +#include "internal.h" + +static void +proc_config(struct pci_access *a) +{ + pci_define_param(a, "proc.path", PCI_PATH_PROC_BUS_PCI, "Path to the procfs bus tree"); +} + +static int +proc_detect(struct pci_access *a) +{ + char *name = pci_get_param(a, "proc.path"); + + if (access(name, R_OK)) + { + a->warning("Cannot open %s", name); + return 0; + } + a->debug("...using %s", name); + return 1; +} + +static void +proc_init(struct pci_access *a) +{ + a->fd = -1; +} + +static void +proc_cleanup(struct pci_access *a) +{ + if (a->fd >= 0) + { + close(a->fd); + a->fd = -1; + } +} + +static void +proc_scan(struct pci_access *a) +{ + FILE *f; + char buf[512]; + + if (snprintf(buf, sizeof(buf), "%s/devices", pci_get_param(a, "proc.path")) == sizeof(buf)) + a->error("File name too long"); + f = fopen(buf, "r"); + if (!f) + a->error("Cannot open %s", buf); + while (fgets(buf, sizeof(buf)-1, f)) + { + struct pci_dev *d = pci_alloc_dev(a); + unsigned int dfn, vend, cnt, known; + char *driver; + int offset; + +#define F " " PCIADDR_T_FMT + cnt = sscanf(buf, "%x %x %x" F F F F F F F F F F F F F F "%n", + &dfn, + &vend, + &d->irq, + &d->base_addr[0], + &d->base_addr[1], + &d->base_addr[2], + &d->base_addr[3], + &d->base_addr[4], + &d->base_addr[5], + &d->rom_base_addr, + &d->size[0], + &d->size[1], + &d->size[2], + &d->size[3], + &d->size[4], + &d->size[5], + &d->rom_size, + &offset); +#undef F + if (cnt != 9 && cnt != 10 && cnt != 17) + a->error("proc: parse error (read only %d items)", cnt); + d->bus = dfn >> 8U; + d->dev = PCI_SLOT(dfn & 0xff); + d->func = PCI_FUNC(dfn & 0xff); + d->vendor_id = vend >> 16U; + d->device_id = vend & 0xffff; + known = 0; + if (!a->buscentric) + { + known |= PCI_FILL_IDENT | PCI_FILL_IRQ | PCI_FILL_BASES; + if (cnt >= 10) + known |= PCI_FILL_ROM_BASE; + if (cnt >= 17) + known |= PCI_FILL_SIZES; + } + if (cnt >= 17) + { + while (buf[offset] && isspace(buf[offset])) + ++offset; + driver = &buf[offset]; + while (buf[offset] && !isspace(buf[offset])) + ++offset; + buf[offset] = '\0'; + if (driver[0]) + { + pci_set_property(d, PCI_FILL_DRIVER, driver); + known |= PCI_FILL_DRIVER; + } + } + d->known_fields = known; + pci_link_dev(a, d); + } + fclose(f); +} + +static int +proc_setup(struct pci_dev *d, int rw) +{ + struct pci_access *a = d->access; + + if (a->cached_dev != d || a->fd_rw < rw) + { + char buf[1024]; + int e; + if (a->fd >= 0) + close(a->fd); + e = snprintf(buf, sizeof(buf), "%s/%02x/%02x.%d", + pci_get_param(a, "proc.path"), + d->bus, d->dev, d->func); + if (e < 0 || e >= (int) sizeof(buf)) + a->error("File name too long"); + a->fd_rw = a->writeable || rw; + a->fd = open(buf, a->fd_rw ? O_RDWR : O_RDONLY); + if (a->fd < 0) + { + e = snprintf(buf, sizeof(buf), "%s/%04x:%02x/%02x.%d", + pci_get_param(a, "proc.path"), + d->domain, d->bus, d->dev, d->func); + if (e < 0 || e >= (int) sizeof(buf)) + a->error("File name too long"); + a->fd = open(buf, a->fd_rw ? O_RDWR : O_RDONLY); + } + if (a->fd < 0) + a->warning("Cannot open %s", buf); + a->cached_dev = d; + } + return a->fd; +} + +static int +proc_read(struct pci_dev *d, int pos, byte *buf, int len) +{ + int fd = proc_setup(d, 0); + int res; + + if (fd < 0) + return 0; + res = pread(fd, buf, len, pos); + if (res < 0) + { + d->access->warning("proc_read: read failed: %s", strerror(errno)); + return 0; + } + else if (res != len) + return 0; + return 1; +} + +static int +proc_write(struct pci_dev *d, int pos, byte *buf, int len) +{ + int fd = proc_setup(d, 1); + int res; + + if (fd < 0) + return 0; + res = pwrite(fd, buf, len, pos); + if (res < 0) + { + d->access->warning("proc_write: write failed: %s", strerror(errno)); + return 0; + } + else if (res != len) + { + d->access->warning("proc_write: tried to write %d bytes at %d, but only %d succeeded", len, pos, res); + return 0; + } + return 1; +} + +static void +proc_cleanup_dev(struct pci_dev *d) +{ + if (d->access->cached_dev == d) + d->access->cached_dev = NULL; +} + +struct pci_methods pm_linux_proc = { + "linux-proc", + "The proc file system on Linux", + proc_config, + proc_detect, + proc_init, + proc_cleanup, + proc_scan, + pci_generic_fill_info, + proc_read, + proc_write, + NULL, /* read_vpd */ + NULL, /* init_dev */ + proc_cleanup_dev +}; |