M7350/system/extras/libpagemap/pm_kernel.c
2024-09-09 08:57:42 +00:00

159 lines
3.5 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 <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <pagemap/pagemap.h>
int pm_kernel_create(pm_kernel_t **ker_out) {
pm_kernel_t *ker;
int error;
if (!ker_out)
return 1;
ker = calloc(1, sizeof(*ker));
if (!ker)
return errno;
ker->kpagecount_fd = open("/proc/kpagecount", O_RDONLY);
if (ker->kpagecount_fd < 0) {
error = errno;
free(ker);
return error;
}
ker->kpageflags_fd = open("/proc/kpageflags", O_RDONLY);
if (ker->kpageflags_fd < 0) {
error = errno;
close(ker->kpagecount_fd);
free(ker);
return error;
}
ker->pagesize = getpagesize();
*ker_out = ker;
return 0;
}
#define INIT_PIDS 20
int pm_kernel_pids(pm_kernel_t *ker, pid_t **pids_out, size_t *len) {
DIR *proc;
struct dirent *dir;
pid_t pid, *pids, *new_pids;
size_t pids_count, pids_size;
int error;
proc = opendir("/proc");
if (!proc)
return errno;
pids = malloc(INIT_PIDS * sizeof(pid_t));
if (!pids) {
closedir(proc);
return errno;
}
pids_count = 0; pids_size = INIT_PIDS;
while ((dir = readdir(proc))) {
if (sscanf(dir->d_name, "%d", &pid) < 1)
continue;
if (pids_count >= pids_size) {
new_pids = realloc(pids, 2 * pids_size * sizeof(pid_t));
if (!new_pids) {
error = errno;
free(pids);
closedir(proc);
return error;
}
pids = new_pids;
pids_size = 2 * pids_size;
}
pids[pids_count] = pid;
pids_count++;
}
closedir(proc);
new_pids = realloc(pids, pids_count * sizeof(pid_t));
if (!new_pids) {
error = errno;
free(pids);
return error;
}
*pids_out = new_pids;
*len = pids_count;
return 0;
}
int pm_kernel_count(pm_kernel_t *ker, uint64_t pfn, uint64_t *count_out) {
off64_t off;
if (!ker || !count_out)
return -1;
off = lseek64(ker->kpagecount_fd, pfn * sizeof(uint64_t), SEEK_SET);
if (off == (off_t)-1)
return errno;
if (read(ker->kpagecount_fd, count_out, sizeof(uint64_t)) <
(ssize_t)sizeof(uint64_t))
return errno;
return 0;
}
int pm_kernel_flags(pm_kernel_t *ker, uint64_t pfn, uint64_t *flags_out) {
off64_t off;
if (!ker || !flags_out)
return -1;
off = lseek64(ker->kpageflags_fd, pfn * sizeof(uint64_t), SEEK_SET);
if (off == (off_t)-1)
return errno;
if (read(ker->kpageflags_fd, flags_out, sizeof(uint64_t)) <
(ssize_t)sizeof(uint64_t))
return errno;
return 0;
}
int pm_kernel_destroy(pm_kernel_t *ker) {
if (!ker)
return -1;
close(ker->kpagecount_fd);
close(ker->kpageflags_fd);
free(ker);
return 0;
}