From: Emil Velikov emil.velikov@collabora.com
Introduce a helper which gets the real sysfs path for the given pci device.
In other words, instead opening the /sys/dev/char/*/device symlink, we opt for the actual /sys/devices/pci*/*/
It folds three (nearly identical) snprintf's and paves the way of adding extra devices (see next patch) a piece of pie.
Signed-off-by: Emil Velikov emil.velikov@collabora.com --- xf86drm.c | 62 ++++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 50 insertions(+), 12 deletions(-)
diff --git a/xf86drm.c b/xf86drm.c index d4810740..8ccd528f 100644 --- a/xf86drm.c +++ b/xf86drm.c @@ -2992,16 +2992,37 @@ static int drmParseSubsystemType(int maj, int min) #endif }
+static char * +get_real_pci_path(int maj, int min) +{ + char path[PATH_MAX + 1]; + char *real_path = malloc(PATH_MAX); + + if (!real_path) + return NULL; + + snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device", maj, min); + if (!realpath(path, real_path)) { + free(real_path); + return NULL; + } + + return real_path; +} + static int drmParsePciBusInfo(int maj, int min, drmPciBusInfoPtr info) { #ifdef __linux__ unsigned int domain, bus, dev, func; - char path[PATH_MAX + 1], *value; + char *real_path, *value; int num;
- snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device", maj, min); + real_path = get_real_pci_path(maj, min); + if (!real_path) + return -ENOENT;
- value = sysfs_uevent_get(path, "PCI_SLOT_NAME"); + value = sysfs_uevent_get(real_path, "PCI_SLOT_NAME"); + free(real_path); if (!value) return -ENOENT;
@@ -3114,24 +3135,32 @@ static int parse_separate_sysfs_files(int maj, int min, "subsystem_vendor", "subsystem_device", }; - char path[PATH_MAX + 1]; + char path[PATH_MAX + 1], *real_path; unsigned int data[ARRAY_SIZE(attrs)]; FILE *fp; int ret;
+ real_path = get_real_pci_path(maj, min); + if (!real_path) + return -ENOENT; + for (unsigned i = ignore_revision ? 1 : 0; i < ARRAY_SIZE(attrs); i++) { - snprintf(path, PATH_MAX, "/sys/dev/char/%d:%d/device/%s", maj, min, - attrs[i]); + snprintf(path, PATH_MAX, "%s/%s", real_path, attrs[i]); fp = fopen(path, "r"); - if (!fp) + if (!fp) { + free(real_path); return -errno; + }
ret = fscanf(fp, "%x", &data[i]); fclose(fp); - if (ret != 1) + if (ret != 1) { + free(real_path); return -errno; + }
} + free(real_path);
device->revision_id = ignore_revision ? 0xff : data[0] & 0xff; device->vendor_id = data[1] & 0xffff; @@ -3145,19 +3174,28 @@ static int parse_separate_sysfs_files(int maj, int min, static int parse_config_sysfs_file(int maj, int min, drmPciDeviceInfoPtr device) { - char path[PATH_MAX + 1]; + char path[PATH_MAX + 1], *real_path; unsigned char config[64]; int fd, ret;
- snprintf(path, PATH_MAX, "/sys/dev/char/%d:%d/device/config", maj, min); + real_path = get_real_pci_path(maj, min); + if (!real_path) + return -ENOENT; + + snprintf(path, PATH_MAX, "%s/config", real_path); fd = open(path, O_RDONLY); - if (fd < 0) + if (fd < 0) { + free(real_path); return -errno; + }
ret = read(fd, config, sizeof(config)); close(fd); - if (ret < 0) + if (ret < 0) { + free(real_path); return -errno; + } + free(real_path);
device->vendor_id = config[0] | (config[1] << 8); device->device_id = config[2] | (config[3] << 8);