Replace manual dm ioctls with libdm.
This mostly 1:1 replaces manual ioctls to device-mapper with calls to
libdm. There were two exceptions:
(1) There is a very old table-load-retry loop to workaround issues with
umount (b/7220345). This loop has been preserved, however, it now
includes DM_DEV_CREATE as well as DM_TABLE_LOAD.
(2) There was some ancient code to set DM_DEV_GEOMETRY for obb
dm-devices. This never did anything since geometry must be set after
loading a table. When setting it before (as vold was doing), the
subsequent DM_TABLE_LOAD will clear it.
Bug: 132206403
Test: FBE device boots
FBE device w/ metadata encryption boots
FDE device boots
atest StorageManagerIntegrationTest
Change-Id: Ib6db6b47329f093ac7084edaf604eddace8b9ac6
diff --git a/Devmapper.cpp b/Devmapper.cpp
index b42467c..d55d92d 100644
--- a/Devmapper.cpp
+++ b/Devmapper.cpp
@@ -23,7 +23,6 @@
#include <string.h>
#include <unistd.h>
-#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
@@ -32,239 +31,72 @@
#include <android-base/logging.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
+#include <libdm/dm.h>
#include <utils/Trace.h>
#include "Devmapper.h"
-#define DEVMAPPER_BUFFER_SIZE 4096
-
using android::base::StringPrintf;
+using namespace android::dm;
static const char* kVoldPrefix = "vold:";
-void Devmapper::ioctlInit(struct dm_ioctl* io, size_t dataSize, const char* name, unsigned flags) {
- memset(io, 0, dataSize);
- io->data_size = dataSize;
- io->data_start = sizeof(struct dm_ioctl);
- io->version[0] = 4;
- io->version[1] = 0;
- io->version[2] = 0;
- io->flags = flags;
- if (name) {
- size_t ret = strlcpy(io->name, name, sizeof(io->name));
- if (ret >= sizeof(io->name)) abort();
- }
-}
-
int Devmapper::create(const char* name_raw, const char* loopFile, const char* key,
unsigned long numSectors, char* ubuffer, size_t len) {
+ auto& dm = DeviceMapper::Instance();
auto name_string = StringPrintf("%s%s", kVoldPrefix, name_raw);
- const char* name = name_string.c_str();
- char* buffer = (char*)malloc(DEVMAPPER_BUFFER_SIZE);
- if (!buffer) {
- PLOG(ERROR) << "Failed malloc";
+ DmTable table;
+ table.Emplace<DmTargetCrypt>(0, numSectors, "twofish", key, 0, loopFile, 0);
+
+ if (!dm.CreateDevice(name_string, table)) {
+ LOG(ERROR) << "Failed to create device-mapper device " << name_string;
return -1;
}
- int fd;
- if ((fd = open("/dev/device-mapper", O_RDWR | O_CLOEXEC)) < 0) {
- PLOG(ERROR) << "Failed open";
- free(buffer);
+ std::string path;
+ if (!dm.GetDmDevicePathByName(name_string, &path)) {
+ LOG(ERROR) << "Failed to get device-mapper device path for " << name_string;
return -1;
}
-
- struct dm_ioctl* io = (struct dm_ioctl*)buffer;
-
- // Create the DM device
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
-
- if (ioctl(fd, DM_DEV_CREATE, io)) {
- PLOG(ERROR) << "Failed DM_DEV_CREATE";
- free(buffer);
- close(fd);
- return -1;
- }
-
- // Set the legacy geometry
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
-
- char* geoParams = buffer + sizeof(struct dm_ioctl);
- // bps=512 spc=8 res=32 nft=2 sec=8190 mid=0xf0 spt=63 hds=64 hid=0 bspf=8 rdcl=2 infs=1 bkbs=2
- strlcpy(geoParams, "0 64 63 0", DEVMAPPER_BUFFER_SIZE - sizeof(struct dm_ioctl));
- geoParams += strlen(geoParams) + 1;
- geoParams = (char*)_align(geoParams, 8);
- if (ioctl(fd, DM_DEV_SET_GEOMETRY, io)) {
- PLOG(ERROR) << "Failed DM_DEV_SET_GEOMETRY";
- free(buffer);
- close(fd);
- return -1;
- }
-
- // Retrieve the device number we were allocated
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
- if (ioctl(fd, DM_DEV_STATUS, io)) {
- PLOG(ERROR) << "Failed DM_DEV_STATUS";
- free(buffer);
- close(fd);
- return -1;
- }
-
- unsigned minor = (io->dev & 0xff) | ((io->dev >> 12) & 0xfff00);
- snprintf(ubuffer, len, "/dev/block/dm-%u", minor);
-
- // Load the table
- struct dm_target_spec* tgt;
- tgt = (struct dm_target_spec*)&buffer[sizeof(struct dm_ioctl)];
-
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, DM_STATUS_TABLE_FLAG);
- io->target_count = 1;
- tgt->status = 0;
-
- tgt->sector_start = 0;
- tgt->length = numSectors;
-
- strlcpy(tgt->target_type, "crypt", sizeof(tgt->target_type));
-
- char* cryptParams = buffer + sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec);
- snprintf(cryptParams,
- DEVMAPPER_BUFFER_SIZE - (sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec)),
- "twofish %s 0 %s 0", key, loopFile);
- cryptParams += strlen(cryptParams) + 1;
- cryptParams = (char*)_align(cryptParams, 8);
- tgt->next = cryptParams - buffer;
-
- if (ioctl(fd, DM_TABLE_LOAD, io)) {
- PLOG(ERROR) << "Failed DM_TABLE_LOAD";
- free(buffer);
- close(fd);
- return -1;
- }
-
- // Resume the new table
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
-
- if (ioctl(fd, DM_DEV_SUSPEND, io)) {
- PLOG(ERROR) << "Failed DM_DEV_SUSPEND";
- free(buffer);
- close(fd);
- return -1;
- }
-
- free(buffer);
-
- close(fd);
+ snprintf(ubuffer, len, "%s", path.c_str());
return 0;
}
int Devmapper::destroy(const char* name_raw) {
+ auto& dm = DeviceMapper::Instance();
+
auto name_string = StringPrintf("%s%s", kVoldPrefix, name_raw);
- const char* name = name_string.c_str();
-
- char* buffer = (char*)malloc(DEVMAPPER_BUFFER_SIZE);
- if (!buffer) {
- PLOG(ERROR) << "Failed malloc";
- return -1;
- }
-
- int fd;
- if ((fd = open("/dev/device-mapper", O_RDWR | O_CLOEXEC)) < 0) {
- PLOG(ERROR) << "Failed open";
- free(buffer);
- return -1;
- }
-
- struct dm_ioctl* io = (struct dm_ioctl*)buffer;
-
- // Create the DM device
- ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
-
- if (ioctl(fd, DM_DEV_REMOVE, io)) {
+ if (!dm.DeleteDevice(name_string)) {
if (errno != ENXIO) {
PLOG(ERROR) << "Failed DM_DEV_REMOVE";
}
- free(buffer);
- close(fd);
return -1;
}
-
- free(buffer);
- close(fd);
return 0;
}
int Devmapper::destroyAll() {
ATRACE_NAME("Devmapper::destroyAll");
- char* buffer = (char*)malloc(1024 * 64);
- if (!buffer) {
- PLOG(ERROR) << "Failed malloc";
- return -1;
- }
- memset(buffer, 0, (1024 * 64));
- char* buffer2 = (char*)malloc(DEVMAPPER_BUFFER_SIZE);
- if (!buffer2) {
- PLOG(ERROR) << "Failed malloc";
- free(buffer);
+ auto& dm = DeviceMapper::Instance();
+ std::vector<DeviceMapper::DmBlockDevice> devices;
+ if (!dm.GetAvailableDevices(&devices)) {
+ LOG(ERROR) << "Failed to get dm devices";
return -1;
}
- int fd;
- if ((fd = open("/dev/device-mapper", O_RDWR | O_CLOEXEC)) < 0) {
- PLOG(ERROR) << "Failed open";
- free(buffer);
- free(buffer2);
- return -1;
- }
-
- struct dm_ioctl* io = (struct dm_ioctl*)buffer;
- ioctlInit(io, (1024 * 64), NULL, 0);
-
- if (ioctl(fd, DM_LIST_DEVICES, io)) {
- PLOG(ERROR) << "Failed DM_LIST_DEVICES";
- free(buffer);
- free(buffer2);
- close(fd);
- return -1;
- }
-
- struct dm_name_list* n = (struct dm_name_list*)(((char*)buffer) + io->data_start);
- if (!n->dev) {
- free(buffer);
- free(buffer2);
- close(fd);
- return 0;
- }
-
- unsigned nxt = 0;
- do {
- n = (struct dm_name_list*)(((char*)n) + nxt);
- auto name = std::string(n->name);
- if (android::base::StartsWith(name, kVoldPrefix)) {
- LOG(DEBUG) << "Tearing down stale dm device named " << name;
-
- memset(buffer2, 0, DEVMAPPER_BUFFER_SIZE);
- struct dm_ioctl* io2 = (struct dm_ioctl*)buffer2;
- ioctlInit(io2, DEVMAPPER_BUFFER_SIZE, n->name, 0);
- if (ioctl(fd, DM_DEV_REMOVE, io2)) {
+ for (const auto& device : devices) {
+ if (android::base::StartsWith(device.name(), kVoldPrefix)) {
+ LOG(DEBUG) << "Tearing down stale dm device named " << device.name();
+ if (!dm.DeleteDevice(device.name())) {
if (errno != ENXIO) {
- PLOG(WARNING) << "Failed to destroy dm device named " << name;
+ PLOG(WARNING) << "Failed to destroy dm device named " << device.name();
}
}
} else {
- LOG(DEBUG) << "Found unmanaged dm device named " << name;
+ LOG(DEBUG) << "Found unmanaged dm device named " << device.name();
}
- nxt = n->next;
- } while (nxt);
-
- free(buffer);
- free(buffer2);
- close(fd);
+ }
return 0;
}
-
-void* Devmapper::_align(void* ptr, unsigned int a) {
- unsigned long agn = --a;
-
- return (void*)(((unsigned long)ptr + agn) & ~agn);
-}