/* * udev_sysfs.c - sysfs linux kernel specific knowledge * * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com> * * 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 version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include <stdio.h> #include <stddef.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <ctype.h> #include <errno.h> #include <sys/stat.h> #include "libsysfs/sysfs/libsysfs.h" #include "udev_version.h" #include "udev_sysfs.h" #include "udev_utils.h" #include "logging.h" /* list of subsystem specific files, NULL if there is no file to wait for */ static const struct subsystem_file { const char *subsystem; const char *file; } subsystem_files[] = { { .subsystem = "class", .file = NULL }, { .subsystem = "net", .file = "ifindex" }, { .subsystem = "scsi_host", .file = "unique_id" }, { .subsystem = "scsi_device", .file = NULL }, { .subsystem = "pcmcia_socket", .file = "card_type" }, { .subsystem = "usb_host", .file = NULL }, { .subsystem = "bluetooth", .file = "address" }, { .subsystem = "firmware", .file = "data" }, { .subsystem = "i2c-adapter", .file = NULL }, { .subsystem = "pci_bus", .file = NULL }, { .subsystem = "ieee1394", .file = NULL }, { .subsystem = "ieee1394_host", .file = NULL }, { .subsystem = "ieee1394_node", .file = NULL }, { .subsystem = "fc_transport", .file = "port_id" }, { .subsystem = "fc_host", .file = "port_id" }, { .subsystem = "spi_transport", .file = "width" }, { .subsystem = "spi_host", .file = "width" }, { NULL, NULL } }; dev_t get_devt(struct sysfs_class_device *class_dev) { struct sysfs_attribute *attr = NULL; unsigned int major, minor; attr = sysfs_get_classdev_attr(class_dev, "dev"); if (attr == NULL) return 0; dbg("dev='%s'", attr->value); if (sscanf(attr->value, "%u:%u", &major, &minor) != 2) return 0; dbg("found major=%d, minor=%d", major, minor); return makedev(major, minor); } int subsystem_expect_no_dev(const char *subsystem) { const struct subsystem_file *file; for (file = subsystem_files; file->subsystem != NULL; file++) if (strcmp(subsystem, file->subsystem) == 0) return 1; return 0; } /* get subsystem specific files, returns "dev" if no other found */ static const char *get_subsystem_specific_file(const char *subsystem) { const struct subsystem_file *file; /* look if we want to look for another file instead of "dev" */ for (file = subsystem_files; file->subsystem != NULL; file++) if (strcmp(subsystem, file->subsystem) == 0) return file->file; return "dev"; } /* wait for class pecific file to show up */ static int wait_for_class_device_attributes(struct sysfs_class_device *class_dev, const char **error) { const char *file; char filename[PATH_SIZE]; int loop; file = get_subsystem_specific_file(class_dev->classname); if (file == NULL) { dbg("class '%s' has no file to wait for", class_dev->classname); return 0; } snprintf(filename, sizeof(filename), "%s/%s", class_dev->path, file); filename[sizeof(filename)-1] = '\0'; dbg("looking at class '%s' for specific file '%s'", class_dev->classname, filename); loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { struct stat stats; if (stat(class_dev->path, &stats) == -1) { dbg("'%s' now disappeared (probably remove has beaten us)", class_dev->path); return -ENODEV; } if (stat(filename, &stats) == 0) { dbg("class '%s' specific file '%s' found", class_dev->classname, file); return 0; } usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } dbg("error: getting class '%s' specific file '%s'", class_dev->classname, file); if (error) *error = "class specific file unavailable"; return -ENOENT; } /* check if we need to wait for a physical device */ static int class_device_expect_no_device_link(struct sysfs_class_device *class_dev) { /* list of devices without a "device" symlink to the physical device * if device is set to NULL, no devices in that subsystem has a link */ static const struct class_device { const char *subsystem; const char *device; } class_device[] = { { .subsystem = "block", .device = "double" }, { .subsystem = "block", .device = "nb" }, { .subsystem = "block", .device = "ram" }, { .subsystem = "block", .device = "loop" }, { .subsystem = "block", .device = "fd" }, { .subsystem = "block", .device = "md" }, { .subsystem = "block", .device = "dos_cd" }, { .subsystem = "block", .device = "rflash" }, { .subsystem = "block", .device = "rom" }, { .subsystem = "block", .device = "rrom" }, { .subsystem = "block", .device = "flash" }, { .subsystem = "block", .device = "msd" }, { .subsystem = "block", .device = "sbpcd" }, { .subsystem = "block", .device = "pcd" }, { .subsystem = "block", .device = "pf" }, { .subsystem = "block", .device = "scd" }, { .subsystem = "block", .device = "ubd" }, { .subsystem = "block", .device = "dm-" }, { .subsystem = "block", .device = "bcrypt" }, { .subsystem = "input", .device = "event" }, { .subsystem = "input", .device = "mice" }, { .subsystem = "input", .device = "mouse" }, { .subsystem = "input", .device = "ts" }, { .subsystem = "input", .device = "js" }, { .subsystem = "vc", .device = NULL }, { .subsystem = "tty", .device = NULL }, { .subsystem = "cpuid", .device = "cpu" }, { .subsystem = "graphics", .device = "fb" }, { .subsystem = "mem", .device = NULL }, { .subsystem = "misc", .device = NULL }, { .subsystem = "msr", .device = NULL }, { .subsystem = "netlink", .device = NULL }, { .subsystem = "net", .device = "sit" }, { .subsystem = "net", .device = "lo" }, { .subsystem = "net", .device = "tap" }, { .subsystem = "net", .device = "ipsec" }, { .subsystem = "net", .device = "dummy" }, { .subsystem = "net", .device = "irda" }, { .subsystem = "net", .device = "ppp" }, { .subsystem = "net", .device = "tun" }, { .subsystem = "net", .device = "pan" }, { .subsystem = "net", .device = "bnep" }, { .subsystem = "net", .device = "vmnet" }, { .subsystem = "net", .device = "ippp" }, { .subsystem = "net", .device = "nlv" }, { .subsystem = "net", .device = "atml" }, { .subsystem = "ppp", .device = NULL }, { .subsystem = "sound", .device = NULL }, { .subsystem = "printer", .device = "lp" }, { .subsystem = "ppdev", .device = NULL }, { .subsystem = "nvidia", .device = NULL }, { .subsystem = "video4linux", .device = "vbi" }, { .subsystem = "dvb", .device = NULL }, { .subsystem = "lirc", .device = NULL }, { .subsystem = "firmware", .device = NULL }, { .subsystem = "drm", .device = NULL }, { .subsystem = "pci_bus", .device = NULL }, { .subsystem = "ieee1394", .device = NULL }, { .subsystem = "ieee1394_host", .device = NULL }, { .subsystem = "ieee1394_node", .device = NULL }, { .subsystem = "raw", .device = NULL }, { .subsystem = "zaptel", .device = NULL }, { .subsystem = "tiglusb", .device = NULL }, { .subsystem = "ppdev", .device = NULL }, { .subsystem = "ticables", .device = NULL }, { .subsystem = "snsc", .device = NULL }, { .subsystem = "staliomem", .device = NULL }, { .subsystem = "tape", .device = NULL }, { .subsystem = "ip2", .device = NULL }, { .subsystem = "tpqic02", .device = NULL }, { .subsystem = "dsp56k", .device = NULL }, { .subsystem = "zft", .device = NULL }, { .subsystem = "adb", .device = NULL }, { .subsystem = "cosa", .device = NULL }, { .subsystem = "pg", .device = NULL }, { .subsystem = "pt", .device = NULL }, { .subsystem = "capi", .device = NULL }, { NULL, NULL } }; const struct class_device *classdevice; unsigned int len; /* the kernel may tell us what to wait for */ if (kernel_release_satisfactory(2,6,10) > 0) if (getenv("PHYSDEVPATH") == NULL) { dbg("the kernel says, that there is no physical device for '%s'", class_dev->path); return 1; } for (classdevice = class_device; classdevice->subsystem != NULL; classdevice++) { if (strcmp(class_dev->classname, classdevice->subsystem) == 0) { /* see if no device in this class is expected to have a device-link */ if (classdevice->device == NULL) return 1; len = strlen(classdevice->device); /* see if device name matches */ if (strncmp(class_dev->name, classdevice->device, len) != 0) continue; /* exact name match */ if (strlen(class_dev->name) == len) return 1; /* name match with instance number */ if (isdigit(class_dev->name[len])) return 1; } } return 0; } /* skip waiting for the bus of the devices device */ static int class_device_expect_no_bus(struct sysfs_class_device *class_dev) { static const char *devices_without_bus[] = { "scsi_host", "i2c-adapter", "i2c-dev", NULL }; const char **device; for (device = devices_without_bus; *device != NULL; device++) { int len = strlen(*device); if (strncmp(class_dev->classname, *device, len) == 0) return 1; } return 0; } /* wait for a devices device specific file to show up */ int wait_for_devices_device(struct sysfs_device *devices_dev, const char **error) { static const struct device_file { const char *bus; const char *file; } device_files[] = { { .bus = "scsi", .file = "vendor" }, { .bus = "usb", .file = "idVendor" }, { .bus = "usb", .file = "iInterface" }, { .bus = "usb", .file = "bNumEndpoints" }, { .bus = "usb-serial", .file = "detach_state" }, { .bus = "ide", .file = "detach_state" }, { .bus = "pci", .file = "vendor" }, { .bus = "platform", .file = "detach_state" }, { .bus = "pcmcia", .file = "detach_state" }, { .bus = "i2c", .file = "detach_state" }, { .bus = "ieee1394", .file = "node_count" }, { .bus = "ieee1394", .file = "nodeid" }, { .bus = "ieee1394", .file = "address" }, { .bus = "bttv-sub", .file = NULL }, { .bus = "pnp", .file = "detach_state" }, { .bus = "eisa", .file = "detach_state" }, { .bus = "serio", .file = "detach_state" }, { .bus = "pseudo", .file = "detach_state" }, { .bus = "mmc", .file = "detach_state" }, { .bus = "macio", .file = "detach_state" }, { .bus = "of_platform", .file = "detach_state" }, { .bus = "vio", .file = "detach_state" }, { .bus = "ecard", .file = "detach_state" }, { .bus = "sa1111-rab", .file = "detach_state" }, { .bus = "amba", .file = "detach_state" }, { .bus = "locomo-bus", .file = "detach_state" }, { .bus = "logicmodule", .file = "detach_state" }, { .bus = "parisc", .file = "detach_state" }, { .bus = "ocp", .file = "detach_state" }, { .bus = "dio", .file = "detach_state" }, { .bus = "MCA", .file = "detach_state" }, { .bus = "wl", .file = "detach_state" }, { .bus = "ccwgroup", .file = "detach_state" }, { .bus = "css", .file = "detach_state" }, { .bus = "ccw", .file = "detach_state" }, { .bus = "iucv", .file = "detach_state" }, { NULL, NULL } }; const struct device_file *devicefile = NULL; int loop; /* the kernel may tell us what to wait for */ if (kernel_release_satisfactory(2,6,10) > 0) if (getenv("PHYSDEVBUS") == NULL) { dbg("the kernel says, that there is no bus for '%s'", devices_dev->path); return 0; } /* wait for the bus device link to the devices device */ loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { if (sysfs_get_device_bus(devices_dev) == 0) break; usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } if (loop == 0) { dbg("error: getting bus device link"); if (error) *error = "no bus device link"; return -1; } dbg("bus device link found for bus '%s'", devices_dev->bus); /* wait for a bus device specific file to show up */ loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { int found_bus_type = 0; for (devicefile = device_files; devicefile->bus != NULL; devicefile++) { if (strcmp(devices_dev->bus, devicefile->bus) == 0) { char filename[PATH_SIZE]; struct stat stats; if (devicefile->file == NULL) { dbg("bus '%s' has no file to wait for", devices_dev->bus); return 0; } found_bus_type = 1; snprintf(filename, sizeof(filename), "%s/%s", devices_dev->path, devicefile->file); filename[sizeof(filename)-1] = '\0'; dbg("looking at bus '%s' device for specific file '%s'", devices_dev->bus, filename); if (stat(filename, &stats) == 0) { dbg("bus '%s' device specific file '%s' found", devices_dev->bus, devicefile->file); return 0; } } } if (found_bus_type == 0) { if (error) *error = "unknown bus"; info("error: unknown bus, please report to " "<linux-hotplug-devel@lists.sourceforge.net> '%s'", devices_dev->bus); return -1; } usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } dbg("error: getting '%s' device specific file '%s'", devices_dev->bus, devicefile->file); if (error) *error = "bus device specific file unavailable"; return -1; } struct sysfs_class_device *wait_class_device_open(const char *path) { struct sysfs_class_device *class_dev = NULL; int loop; loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { class_dev = sysfs_open_class_device_path(path); if (class_dev) break; usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } return class_dev; } int wait_for_class_device(struct sysfs_class_device *class_dev, const char **error) { struct sysfs_class_device *class_dev_parent; struct sysfs_device *devices_dev = NULL; int loop; if (wait_for_class_device_attributes(class_dev, error) != 0) return -ENOENT; /* skip devices without devices-link */ if (class_device_expect_no_device_link(class_dev)) { dbg("no device symlink expected for '%s', ", class_dev->name); return 0; } /* the symlink may be on the parent device */ class_dev_parent = sysfs_get_classdev_parent(class_dev); if (class_dev_parent) dbg("looking at parent device for device link '%s'", class_dev_parent->path); /* wait for the symlink to the devices device */ dbg("waiting for symlink to devices device"); loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { if (class_dev_parent) devices_dev = sysfs_get_classdev_device(class_dev_parent); else devices_dev = sysfs_get_classdev_device(class_dev); if (devices_dev) break; usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } if (!devices_dev) { dbg(" error: no devices device symlink found"); if (error) *error = "no device symlink"; return -ENODEV; } dbg("device symlink found pointing to '%s'", devices_dev->path); /* wait for the devices device */ if (class_device_expect_no_bus(class_dev)) { dbg("no bus device expected for '%s', ", class_dev->classname); return 0; } return wait_for_devices_device(devices_dev, error); } struct sysfs_device *wait_devices_device_open(const char *path) { struct sysfs_device *devices_dev = NULL; int loop; loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND; while (--loop) { devices_dev = sysfs_open_device_path(path); if (devices_dev) break; usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND); } return devices_dev; }