platform_system_core/vold/uevent.c
2009-03-18 17:39:49 -07:00

441 lines
12 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "vold.h"
#include "uevent.h"
#include "mmc.h"
#include "blkdev.h"
#include "volmgr.h"
#include "media.h"
#define DEBUG_UEVENT 0
#define UEVENT_PARAMS_MAX 32
enum uevent_action { action_add, action_remove, action_change };
struct uevent {
char *path;
enum uevent_action action;
char *subsystem;
char *param[UEVENT_PARAMS_MAX];
unsigned int seqnum;
};
struct uevent_dispatch {
char *subsystem;
int (* dispatch) (struct uevent *);
};
static void dump_uevent(struct uevent *);
static int dispatch_uevent(struct uevent *event);
static void free_uevent(struct uevent *event);
static char *get_uevent_param(struct uevent *event, char *param_name);
static int handle_powersupply_event(struct uevent *event);
static int handle_switch_event(struct uevent *);
static int handle_battery_event(struct uevent *);
static int handle_mmc_event(struct uevent *);
static int handle_block_event(struct uevent *);
static int handle_bdi_event(struct uevent *);
static void _cb_blkdev_ok_to_destroy(blkdev_t *dev);
static struct uevent_dispatch dispatch_table[] = {
{ "switch", handle_switch_event },
{ "battery", handle_battery_event },
{ "mmc", handle_mmc_event },
{ "block", handle_block_event },
{ "bdi", handle_bdi_event },
{ "power_supply", handle_powersupply_event },
{ NULL, NULL }
};
static boolean low_batt = false;
static boolean door_open = true;
int process_uevent_message(int socket)
{
char buffer[64 * 1024]; // Thank god we're not in the kernel :)
int count;
char *s = buffer;
char *end;
struct uevent *event;
int param_idx = 0;
int i;
int first = 1;
int rc = 0;
if ((count = recv(socket, buffer, sizeof(buffer), 0)) < 0) {
LOGE("Error receiving uevent (%s)", strerror(errno));
return -errno;
}
if (!(event = malloc(sizeof(struct uevent)))) {
LOGE("Error allocating memory (%s)", strerror(errno));
return -errno;
}
memset(event, 0, sizeof(struct uevent));
end = s + count;
while (s < end) {
if (first) {
char *p;
for (p = s; *p != '@'; p++);
p++;
event->path = strdup(p);
first = 0;
} else {
if (!strncmp(s, "ACTION=", strlen("ACTION="))) {
char *a = s + strlen("ACTION=");
if (!strcmp(a, "add"))
event->action = action_add;
else if (!strcmp(a, "change"))
event->action = action_change;
else if (!strcmp(a, "remove"))
event->action = action_remove;
} else if (!strncmp(s, "SEQNUM=", strlen("SEQNUM=")))
event->seqnum = atoi(s + strlen("SEQNUM="));
else if (!strncmp(s, "SUBSYSTEM=", strlen("SUBSYSTEM=")))
event->subsystem = strdup(s + strlen("SUBSYSTEM="));
else
event->param[param_idx++] = strdup(s);
}
s+= strlen(s) + 1;
}
rc = dispatch_uevent(event);
free_uevent(event);
return rc;
}
int simulate_uevent(char *subsys, char *path, char *action, char **params)
{
struct uevent *event;
char tmp[255];
int i, rc;
if (!(event = malloc(sizeof(struct uevent)))) {
LOGE("Error allocating memory (%s)", strerror(errno));
return -errno;
}
memset(event, 0, sizeof(struct uevent));
event->subsystem = strdup(subsys);
if (!strcmp(action, "add"))
event->action = action_add;
else if (!strcmp(action, "change"))
event->action = action_change;
else if (!strcmp(action, "remove"))
event->action = action_remove;
else {
LOGE("Invalid action '%s'", action);
return -1;
}
event->path = strdup(path);
for (i = 0; i < UEVENT_PARAMS_MAX; i++) {
if (!params[i])
break;
event->param[i] = strdup(params[i]);
}
rc = dispatch_uevent(event);
free_uevent(event);
return rc;
}
static int dispatch_uevent(struct uevent *event)
{
int i;
#if DEBUG_UEVENT
dump_uevent(event);
#endif
for (i = 0; dispatch_table[i].subsystem != NULL; i++) {
if (!strcmp(dispatch_table[i].subsystem, event->subsystem))
return dispatch_table[i].dispatch(event);
}
#if DEBUG_UEVENT
LOG_VOL("No uevent handlers registered for '%s' subsystem", event->subsystem);
#endif
return 0;
}
static void dump_uevent(struct uevent *event)
{
int i;
LOG_VOL("[UEVENT] Sq: %u S: %s A: %d P: %s",
event->seqnum, event->subsystem, event->action, event->path);
for (i = 0; i < UEVENT_PARAMS_MAX; i++) {
if (!event->param[i])
break;
LOG_VOL("%s", event->param[i]);
}
}
static void free_uevent(struct uevent *event)
{
int i;
free(event->path);
free(event->subsystem);
for (i = 0; i < UEVENT_PARAMS_MAX; i++) {
if (!event->param[i])
break;
free(event->param[i]);
}
free(event);
}
static char *get_uevent_param(struct uevent *event, char *param_name)
{
int i;
for (i = 0; i < UEVENT_PARAMS_MAX; i++) {
if (!event->param[i])
break;
if (!strncmp(event->param[i], param_name, strlen(param_name)))
return &event->param[i][strlen(param_name) + 1];
}
LOGE("get_uevent_param(): No parameter '%s' found", param_name);
return NULL;
}
/*
* ---------------
* Uevent Handlers
* ---------------
*/
static int handle_powersupply_event(struct uevent *event)
{
char *ps_type = get_uevent_param(event, "POWER_SUPPLY_TYPE");
if (!strcasecmp(ps_type, "battery")) {
char *ps_cap = get_uevent_param(event, "POWER_SUPPLY_CAPACITY");
int capacity = atoi(ps_cap);
if (capacity < 5)
low_batt = true;
else
low_batt = false;
volmgr_safe_mode(low_batt || door_open);
}
return 0;
}
static int handle_switch_event(struct uevent *event)
{
char *name = get_uevent_param(event, "SWITCH_NAME");
char *state = get_uevent_param(event, "SWITCH_STATE");
if (!strcmp(name, "usb_mass_storage")) {
if (!strcmp(state, "online")) {
ums_hostconnected_set(true);
} else {
ums_hostconnected_set(false);
volmgr_enable_ums(false);
}
} else if (!strcmp(name, "sd-door")) {
if (!strcmp(state, "open"))
door_open = true;
else
door_open = false;
volmgr_safe_mode(low_batt || door_open);
} else
LOG_VOL("handle_switch_event(): Ignoring switch '%s'", name);
return 0;
}
static int handle_battery_event(struct uevent *event)
{
return 0;
}
static int handle_block_event(struct uevent *event)
{
char mediapath[255];
media_t *media;
int n;
int maj, min;
blkdev_t *blkdev;
/*
* Look for backing media for this block device
*/
if (!strncmp(get_uevent_param(event, "DEVPATH"),
"/devices/virtual/",
strlen("/devices/virtual/"))) {
n = 0;
} else if (!strcmp(get_uevent_param(event, "DEVTYPE"), "disk"))
n = 2;
else if (!strcmp(get_uevent_param(event, "DEVTYPE"), "partition"))
n = 3;
else {
LOGE("Bad blockdev type '%s'", get_uevent_param(event, "DEVTYPE"));
return -EINVAL;
}
truncate_sysfs_path(event->path, n, mediapath, sizeof(mediapath));
if (!(media = media_lookup_by_path(mediapath, false))) {
#if DEBUG_UEVENT
LOG_VOL("No backend media found @ device path '%s'", mediapath);
#endif
return 0;
}
maj = atoi(get_uevent_param(event, "MAJOR"));
min = atoi(get_uevent_param(event, "MINOR"));
if (event->action == action_add) {
blkdev_t *disk;
/*
* If there isn't a disk already its because *we*
* are the disk
*/
disk = blkdev_lookup_by_devno(maj, 0);
if (!(blkdev = blkdev_create(disk,
event->path,
maj,
min,
media,
get_uevent_param(event, "DEVTYPE")))) {
LOGE("Unable to allocate new blkdev (%m)");
return -1;
}
blkdev_refresh(blkdev);
/*
* Add the blkdev to media
*/
int rc;
if ((rc = media_add_blkdev(media, blkdev)) < 0) {
LOGE("Unable to add blkdev to card (%d)", rc);
return rc;
}
LOGI("New blkdev %d.%d on media %s, media path %s, Dpp %d",
blkdev->major, blkdev->minor, media->name, mediapath,
blkdev_get_num_pending_partitions(blkdev->disk));
if (blkdev_get_num_pending_partitions(blkdev->disk) == 0) {
if ((rc = volmgr_consider_disk(blkdev->disk)) < 0) {
LOGE("Volmgr failed to handle device (%d)", rc);
return rc;
}
}
} else if (event->action == action_remove) {
if (!(blkdev = blkdev_lookup_by_devno(maj, min)))
return 0;
LOGI("Destroying blkdev %d.%d @ %s on media %s", blkdev->major,
blkdev->minor, blkdev->devpath, media->name);
volmgr_notify_eject(blkdev, _cb_blkdev_ok_to_destroy);
} else if (event->action == action_change) {
if (!(blkdev = blkdev_lookup_by_devno(maj, min)))
return 0;
LOGI("Modified blkdev %d.%d @ %s on media %s", blkdev->major,
blkdev->minor, blkdev->devpath, media->name);
blkdev_refresh(blkdev);
} else {
#if DEBUG_UEVENT
LOG_VOL("No handler implemented for action %d", event->action);
#endif
}
return 0;
}
static void _cb_blkdev_ok_to_destroy(blkdev_t *dev)
{
media_t *media = media_lookup_by_dev(dev);
if (media)
media_remove_blkdev(media, dev);
blkdev_destroy(dev);
}
static int handle_bdi_event(struct uevent *event)
{
return 0;
}
static int handle_mmc_event(struct uevent *event)
{
if (event->action == action_add) {
media_t *media;
char serial[80];
char *type;
/*
* Pull card information from sysfs
*/
type = get_uevent_param(event, "MMC_TYPE");
if (strcmp(type, "SD") && strcmp(type, "MMC"))
return 0;
read_sysfs_var(serial, sizeof(serial), event->path, "serial");
if (!(media = media_create(event->path,
get_uevent_param(event, "MMC_NAME"),
serial,
media_mmc))) {
LOGE("Unable to allocate new media (%m)");
return -1;
}
LOGI("New MMC card '%s' (serial %u) added @ %s", media->name,
media->serial, media->devpath);
} else if (event->action == action_remove) {
media_t *media;
if (!(media = media_lookup_by_path(event->path, false))) {
LOGE("Unable to lookup media '%s'", event->path);
return -1;
}
LOGI("MMC card '%s' (serial %u) @ %s removed", media->name,
media->serial, media->devpath);
media_destroy(media);
} else {
#if DEBUG_UEVENT
LOG_VOL("No handler implemented for action %d", event->action);
#endif
}
return 0;
}