diff options
Diffstat (limited to 'balbir/config.c')
| -rw-r--r-- | balbir/config.c | 704 |
1 files changed, 0 insertions, 704 deletions
diff --git a/balbir/config.c b/balbir/config.c deleted file mode 100644 index bed45ce..0000000 --- a/balbir/config.c +++ /dev/null @@ -1,704 +0,0 @@ -/* - * Copyright IBM Corporation. 2007 - * - * Authors: Balbir Singh <balbir@linux.vnet.ibm.com> - * Dhaval Giani <dhaval@linux.vnet.ibm.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of version 2.1 of the GNU Lesser General Public License - * as published by the Free Software Foundation. - * - * This program is distributed in the hope that it would be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. - * - * TODOs: - * 1. Implement our own hashing scheme - * 2. Add namespace support - * 3. Add support for parsing cgroup filesystem and creating a - * config out of it. - * - * Code initiated and designed by Balbir Singh. All faults are most likely - * his mistake. - */ - -#include <assert.h> -#include <dirent.h> -#include <errno.h> -#include <grp.h> -#include <libcgroup.h> -#include <limits.h> -#include <pwd.h> -#include <search.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include <sys/mount.h> -#include <sys/stat.h> -#include <sys/types.h> - -extern FILE *yyin; -extern int yyparse(void); -extern int yydebug; -extern int line_no; -extern int verbose; - -struct hsearch_data group_hash; -struct list_of_names *group_list; -struct mount_table *mount_table; - -const char library_ver[] = "0.01"; -const char cg_filesystem[] = "cgroup"; - -struct cg_group *current_group; - -const char *cg_controller_names[] = { - "cpu", - NULL, -}; - -/* - * File traversal routines require the maximum number of open file - * descriptors to be specified - */ -const int cg_max_openfd = 20; - -/* - * Insert the group into the list of group names we maintain. This helps - * us cleanup nicely - */ -int cg_insert_into_group_list(const char *name) -{ - struct list_of_names *tmp, *curr; - - tmp = malloc(sizeof(*tmp)); - if (!tmp) - return 0; - tmp->next = NULL; - tmp->name = (char *)name; - - if (!group_list) { - group_list = tmp; - return 1; - } - curr = group_list; - while (curr->next) - curr = curr->next; - - curr->next = tmp; - return 1; -} - -/* - * Cleanup the group list. We walk the group list and free the entries in the - * hash tables and controller specific entries. - */ -int cg_cleanup_group_list(void) -{ - struct list_of_names *curr = group_list, *tmp; - ENTRY item, *found_item; - int ret; - struct cg_group *cg_group; - - while (curr) { - tmp = curr; - curr = curr->next; - item.key = tmp->name; - ret = hsearch_r(item, FIND, &found_item, &group_hash); - if (!ret) { - printf("Most likely a bug in the code\n"); - continue; - } - /* - * Free the name and it's value - */ - free(tmp->name); - cg_group = (struct cg_group *)found_item->data; - /* - * Controller specific cleanup - */ - if (cg_group->cpu_config.shares) - free(cg_group->cpu_config.shares); - - free(found_item->data); - } - - return 1; -} - -/* - * Find and walk the mount_table structures to find the specified controller - * name. This routine is *NOT* thread safe. - */ -struct mount_table *cg_find_mount_info(const char *controller_name) -{ - struct mount_table *curr = mount_table; - char *str; - - while (curr) { - str = curr->options; - if (!str) - return NULL; - - str = strtok(curr->options, ","); - do { - if (!strncmp(str, controller_name, strlen(str))) - return curr; - str = strtok(NULL, ","); - } while(str); - curr = curr->next; - } - return NULL; -} - -int cg_cpu_controller_settings(struct cg_group *cg_group, - const char *group_path) -{ - int ret = 1; - char *shares_file; - - shares_file = malloc(strlen(group_path) + strlen("/cpu.shares") + 1); - if (!shares_file) - return 0; - - strncpy(shares_file, group_path, strlen(group_path)); - shares_file = strncat(shares_file, "/cpu.shares", - strlen("/cpu.shares")); - dbg("shares file is %s\n", shares_file); - if (cg_group->cpu_config.shares) { - FILE *fd = fopen(shares_file, "rw+"); - if (!fd) - goto cleanup_shares; - /* - * Assume that one write will do it for us - */ - fwrite(cg_group->cpu_config.shares, - strlen(cg_group->cpu_config.shares), 1, fd); - fclose(fd); - } -cleanup_shares: - free(shares_file); - return ret; -} - -int cg_controller_handle_option(struct cg_group *cg_group, - const char *cg_controller_name, - const char *group_path) -{ - int ret = 0; - if (!strncmp(cg_controller_name, "cpu", strlen("cpu"))) { - ret = cg_cpu_controller_settings(cg_group, group_path); - } else - assert(0); - return ret; -} - -int cg_create_group(struct cg_group *cg_group) -{ - int i, ret; - struct mount_table *mount_info; - char *group_path, *tasks_file, *shares_file; - - dbg("found group %s\n", cg_group->name); - - for (i = 0; cg_controller_names[i]; i++) { - - /* - * Find the mount point related information - */ - mount_info = cg_find_mount_info(cg_controller_names[i]); - dbg("mount_info for controller %s:%s\n", - mount_info->mount_point, cg_controller_names[i]); - if (!mount_info) - return 0; - - /* - * TODO: Namespace support is most likely going to be - * plugged in here - */ - - /* - * Find the path to the group directory - */ - group_path = cg_build_group_path(cg_group, mount_info); - if (!group_path) - goto cleanup_group; - - /* - * Create the specified directory. Errors are ignored. - * If the directory already exists, we are most likely - * OK - */ - ret = cg_make_directory(cg_group, group_path); - if (!ret && (errno != EEXIST)) - goto cleanup_dir; - - /* - * Find the tasks file, should probably be encapsulated - * like we encapsulate cg_build_group_path - */ - tasks_file = malloc(strlen(group_path) + strlen("/tasks") + 1); - if (!tasks_file) - goto cleanup_dir; - strncpy(tasks_file, group_path, strlen(group_path)); - tasks_file = strncat(tasks_file, "/tasks", strlen("/tasks")); - dbg("tasks file is %s\n", tasks_file); - - /* - * Assign task file ownership - */ - ret = chown(tasks_file, cg_group->tasks_uid, - cg_group->tasks_gid); - if (ret < 0) - goto cleanup_perm; - - /* - * Controller specific work, errors are not fatal. - */ - cg_controller_handle_option(cg_group, cg_controller_names[i], - group_path); - free(tasks_file); - free(group_path); - } - return 1; -cleanup_perm: - rmdir(group_path); -cleanup_dir: - free(group_path); -cleanup_group: - return 0; -} - -/* - * Go ahead and create the groups in the filesystem. This routine will need - * to be revisited everytime new controllers are added. - */ -int cg_create_groups(void) -{ - struct list_of_names *curr = group_list, *tmp; - ENTRY item, *found_item; - struct cg_group *cg_group; - int ret = 1; - - while (curr) { - tmp = curr; - curr = curr->next; - item.key = tmp->name; - ret = hsearch_r(item, FIND, &found_item, &group_hash); - if (!ret) - return 0; - cg_group = (struct cg_group *)found_item->data; - ret = cg_create_group(cg_group); - if (!ret) - break; - } - - return ret; -} - -/* - * Go ahead and create the groups in the filesystem. This routine will need - * to be revisited everytime new controllers are added. - */ -int cg_destroy_groups(void) -{ - struct list_of_names *curr = group_list, *tmp; - ENTRY item, *found_item; - struct cg_group *cg_group; - int ret; - struct mount_table *mount_info; - char *group_path; - - while (curr) { - tmp = curr; - curr = curr->next; - item.key = tmp->name; - ret = hsearch_r(item, FIND, &found_item, &group_hash); - if (!ret) - return 0; - cg_group = (struct cg_group *)found_item->data; - mount_info = cg_find_mount_info("cpu"); - dbg("mount_info for cpu %s\n", mount_info->mount_point); - if (!mount_info) - return 0; - group_path = malloc(strlen(mount_info->mount_point) + - strlen(cg_group->name) + 2); - if (!group_path) - return 0; - strncpy(group_path, mount_info->mount_point, - strlen(mount_info->mount_point) + 1); - dbg("group_path is %s\n", group_path); - strncat(group_path, "/", strlen("/")); - strncat(group_path, cg_group->name, strlen(cg_group->name)); - dbg("group_path is %s\n", group_path); - /* - * We might strategically add migrate tasks here, so that - * rmdir is successful. TODO: Later - */ - ret = rmdir(group_path); - if (ret < 0) - goto err; - } - - return 1; -err: - free(group_path); - return 0; -} -/* - * The cg_get_current_group routine is used by the parser to figure out - * the current group that is being built and fill it in with the information - * as it parses through the configuration file - */ -struct cg_group *cg_get_current_group(void) -{ - if (!current_group) - current_group = calloc(1, sizeof(*current_group)); - - return current_group; -} - -/* - * This routine should be invoked when the current group being parsed is - * completely parsed - */ -void cg_put_current_group(void) -{ - /* - * NOTE: we do not free the group, the group is installed into the - * hash table, the cleanup routine will do the freeing of the group - */ - current_group = NULL; -} - -int cg_insert_group(const char *group_name) -{ - struct cg_group *cg_group = cg_get_current_group(); - ENTRY item, *found_item; - int ret; - - if (!cg_group) - return 0; - /* - * Dont' copy the name over, just point to it - */ - cg_group->name = (char *)group_name; - item.key = (char *)group_name; - item.data = cg_group; - dbg("Inserting %s into hash table\n", group_name); - ret = hsearch_r(item, ENTER, &found_item, &group_hash); - if (!ret) { - if (found_item) - errno = EEXIST; - errno = ENOMEM; - goto err; - } - ret = cg_insert_into_group_list(group_name); - if (!ret) - goto err; - dbg("Inserted %s into hash and list\n", group_name); - cg_put_current_group(); - return 1; -err: - cg_cleanup_group_list(); - return 0; -} - -/* - * Because of the way parsing works (bottom-up, shift-reduce), we don't - * know the name of the controller yet. Compilers build an AST and use - * a symbol table to deal with this problem. This code does simple things - * like concatinating strings and passing them upwards. This routine is - * *NOT* thread safe. - * - * This code will need modification everytime new controller support is - * added. - */ -int cg_parse_controller_options(char *controller, char *name_value) -{ - struct cg_group *cg_group = cg_get_current_group(); - char *name, *value; - - if (!cg_group) - return 0; - - if (!strncmp(controller, "cpu", strlen("cpu"))) { - name = strtok(name_value, " "); - value = strtok(NULL, " "); - if (!strncmp(name, "cpu.shares", strlen("cpu.shares"))) - cg_group->cpu_config.shares = strdup(value); - else { - free(controller); - free(name_value); - return 0; - } - dbg("cpu name %s value %s\n", name, value); - } else { - return 0; - } - free(controller); - free(name_value); - return 1; -} - -/* - * Convert the uid/gid field and supplied value to appropriate task - * permissions. This routine is *NOT* thread safe. - */ -int cg_group_task_perm(char *perm_type, char *value) -{ - struct cg_group *cg_group = cg_get_current_group(); - struct passwd *pw; - struct group *group; - long val = atoi(value); - if (!strncmp(perm_type, "uid", strlen("uid"))) { - if (!val) { /* We got the identifier as a name */ - pw = getpwnam(value); - if (!pw) { - free(perm_type); - free(value); - return 0; - } else { - cg_group->tasks_uid = pw->pw_uid; - } - } else { - cg_group->tasks_uid = val; - } - dbg("TASKS %s: %d\n", perm_type, cg_group->tasks_uid); - } - if (!strncmp(perm_type, "gid", strlen("gid"))) { - if (!val) { /* We got the identifier as a name */ - group = getgrnam(value); - if (!group) { - free(perm_type); - free(value); - return 0; - } else { - cg_group->tasks_gid = group->gr_gid; - } - } else { - cg_group->tasks_gid = val; - } - dbg("TASKS %s: %d\n", perm_type, cg_group->tasks_gid); - } - free(perm_type); - free(value); - return 1; -} - -int cg_group_admin_perm(char *perm_type, char *value) -{ - struct cg_group *cg_group = cg_get_current_group(); - struct passwd *pw; - struct group *group; - long val = atoi(value); - if (!strncmp(perm_type, "uid", strlen("uid"))) { - if (!val) { /* We got the identifier as a name */ - pw = getpwnam(value); - if (!pw) { - free(perm_type); - free(value); - return 0; - } else { - cg_group->admin_uid = pw->pw_uid; - } - } else { - cg_group->admin_uid = val; - } - dbg("ADMIN %s: %d\n", perm_type, cg_group->admin_uid); - } - if (!strncmp(perm_type, "gid", strlen("gid"))) { - if (!val) { /* We got the identifier as a name */ - group = getgrnam(value); - if (!group) { - free(perm_type); - free(value); - return 0; - } else { - cg_group->admin_gid = group->gr_gid; - } - } else { - cg_group->admin_gid = val; - } - dbg("ADMIN %s: %d\n", perm_type, - cg_group->admin_gid); - } - free(perm_type); - free(value); - return 1; -} - -/* - * We maintain a hash table. The group hash table maintains the parameters for - * each group, including the parameters for each controller - * - * TODO: Make the initialization a run time configuration parameter - */ -int cg_init_group_and_mount_info(void) -{ - int ret; - - group_list = NULL; - mount_table = NULL; - current_group = NULL; - - ret = hcreate_r(MAX_GROUP_ELEMENTS, &group_hash); - if (!ret) - return 0; - return 1; -} - -/* - * This routine should be called only once all elements of the hash table have - * been freed. Otherwise, we'll end up with a memory leak. - */ -void cg_destroy_group_and_mount_info(void) -{ - hdestroy_r(&group_hash); - group_list = NULL; - mount_table = NULL; - current_group = NULL; -} - -/* - * Insert a name, mount_point pair into the mount_table data structure - * TODO: Validate names and mount points - */ -int cg_insert_into_mount_table(const char *name, const char *mount_point) -{ - struct mount_table *tmp, *prev = mount_table; - - while (prev && prev->next != NULL && - (strncmp(mount_point, prev->mount_point, strlen(mount_point)))) - prev = prev->next; - - if (prev && - !(strncmp(mount_point, prev->mount_point, strlen(mount_point)))) { - prev->options = realloc(prev->options, strlen(prev->options) - + strlen(name) + 2); - if (!prev->options) - return 0; - strncat(prev->options, ",", strlen(",")); - strncat(prev->options, name, strlen(name)); - dbg("options %s: mount_point %s\n", prev->options, - prev->mount_point); - return 1; - } - - tmp = malloc(sizeof(*tmp)); - if (!tmp) - return 0; - - tmp->next = NULL; - tmp->mount_point = (char *)mount_point; - tmp->options = (char *)name; - dbg("options %s: mount_point %s\n", tmp->options, tmp->mount_point); - - if (!prev) { - mount_table = tmp; - return 1; - } else { - prev->next = tmp; - } - - return 1; -} - -void cg_cleanup_mount_table(void) -{ - struct mount_table *curr = mount_table, *tmp; - - while (curr) { - tmp = curr; - curr = curr->next; - tmp->next = NULL; - - /* - * Some of this data might have been allocated by the lexer - * while parsing tokens - */ - free(tmp->mount_point); - free(tmp->options); - - free(tmp); - } -} - -int cg_load_config(const char *pathname) -{ - yyin = fopen(pathname, "rw"); - if (!yyin) { - dbg("Failed to open file %s\n", pathname); - return 0; - } - - if (!cg_init_group_and_mount_info()) - return 0; - - if (yyparse() != 0) { - dbg("Failed to parse file %s\n", pathname); - return 0; - } - - if (!cg_mount_controllers()) - goto err_mnt; - if (!cg_create_groups()) - goto err_grp; - - fclose(yyin); - return 1; -err_grp: - cg_destroy_groups(); - cg_cleanup_group_list(); -err_mnt: - cg_unmount_controllers(); - cg_cleanup_mount_table(); - fclose(yyin); - return 0; -} - -void cg_unload_current_config(void) -{ - cg_destroy_groups(); - cg_cleanup_group_list(); - cg_unmount_controllers(); - cg_cleanup_mount_table(); - cg_destroy_group_and_mount_info(); -} - -int main(int argc, char *argv[]) -{ - int c; - char filename[PATH_MAX]; - int ret; - - if (argc < 2) { - fprintf(stderr, "usage is %s <option> <config file>\n", - argv[0]); - exit(2); - } - - while ((c = getopt(argc, argv, "l:ur:")) > 0) { - switch (c) { - case 'u': - cg_unload_current_config(); - break; - case 'r': - cg_unload_current_config(); - /* FALLTHROUGH */ - case 'l': - strncpy(filename, optarg, PATH_MAX); - ret = cg_load_config(filename); - if (!ret) - exit(3); - break; - default: - fprintf(stderr, "Invalid command line option\n"); - break; - } - } - - cg_destroy_group_and_mount_info(); -} |