+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <errno.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/sysinfo.h>
-#include <sys/inotify.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <unistd.h>
-
-#include "log.h"
-#include "readahead-common.h"
-#include "util.h"
-#include "missing.h"
-#include "fileio.h"
-#include "libudev.h"
-#include "udev-util.h"
-
-int file_verify(int fd, const char *fn, off_t file_size_max, struct stat *st) {
- assert(fd >= 0);
- assert(fn);
- assert(st);
-
- if (fstat(fd, st) < 0) {
- log_warning("fstat(%s) failed: %m", fn);
- return -errno;
- }
-
- if (!S_ISREG(st->st_mode)) {
- log_debug("Not preloading special file %s", fn);
- return 0;
- }
-
- if (st->st_size <= 0 || st->st_size > file_size_max) {
- assert_cc(sizeof(st->st_size) == 8);
- log_debug("Not preloading file %s with size out of bounds %"PRIu64,
- fn, st->st_size);
- return 0;
- }
-
- return 1;
-}
-
-int fs_on_ssd(const char *p) {
- struct stat st;
- _cleanup_udev_unref_ struct udev *udev = NULL;
- _cleanup_udev_device_unref_ struct udev_device *udev_device = NULL;
- struct udev_device *look_at = NULL;
- const char *devtype, *rotational, *model, *id;
- int r;
-
- assert(p);
-
- if (stat(p, &st) < 0)
- return -errno;
-
- if (major(st.st_dev) == 0) {
- _cleanup_fclose_ FILE *f = NULL;
- int mount_id;
- union file_handle_union h = { .handle.handle_bytes = MAX_HANDLE_SZ, };
-
- /* Might be btrfs, which exposes "ssd" as mount flag if it is on ssd.
- *
- * We first determine the mount ID here, if we can,
- * and then lookup the mount ID in mountinfo to find
- * the mount options. */
-
- r = name_to_handle_at(AT_FDCWD, p, &h.handle, &mount_id, AT_SYMLINK_FOLLOW);
- if (r < 0)
- return false;
-
- f = fopen("/proc/self/mountinfo", "re");
- if (!f)
- return false;
-
- for (;;) {
- char line[LINE_MAX], *e;
- _cleanup_free_ char *opts = NULL;
- int mid;
-
- if (!fgets(line, sizeof(line), f))
- return false;
-
- truncate_nl(line);
-
- if (sscanf(line, "%i", &mid) != 1)
- continue;
-
- if (mid != mount_id)
- continue;
-
- e = strstr(line, " - ");
- if (!e)
- continue;
-
- if (sscanf(e+3, "%*s %*s %ms", &opts) != 1)
- continue;
-
- if (streq(opts, "ssd") || startswith(opts, "ssd,") || endswith(opts, ",ssd") || strstr(opts, ",ssd,"))
- return true;
- }
-
- return false;
- }
-
- udev = udev_new();
- if (!udev)
- return -ENOMEM;
-
- udev_device = udev_device_new_from_devnum(udev, 'b', st.st_dev);
- if (!udev_device)
- return false;
-
- devtype = udev_device_get_property_value(udev_device, "DEVTYPE");
- if (devtype && streq(devtype, "partition"))
- look_at = udev_device_get_parent(udev_device);
- else
- look_at = udev_device;
-
- if (!look_at)
- return false;
-
- /* First, try high-level property */
- id = udev_device_get_property_value(look_at, "ID_SSD");
- if (id)
- return streq(id, "1");
-
- /* Second, try kernel attribute */
- rotational = udev_device_get_sysattr_value(look_at, "queue/rotational");
- if (rotational)
- return streq(rotational, "0");
-
- /* Finally, fallback to heuristics */
- look_at = udev_device_get_parent(look_at);
- if (!look_at)
- return false;
-
- model = udev_device_get_sysattr_value(look_at, "model");
- if (model)
- return !!strstr(model, "SSD");
-
- return false;
-}
-
-int fs_on_read_only(const char *p) {
- struct stat st;
- _cleanup_udev_unref_ struct udev *udev = NULL;
- _cleanup_udev_device_unref_ struct udev_device *udev_device = NULL;
- const char *read_only;
-
- assert(p);
-
- if (stat(p, &st) < 0)
- return -errno;
-
- if (major(st.st_dev) == 0)
- return false;
-
- udev = udev_new();
- if (!udev)
- return -ENOMEM;
-
- udev_device = udev_device_new_from_devnum(udev, 'b', st.st_dev);
- if (!udev_device)
- return false;
-
- read_only = udev_device_get_sysattr_value(udev_device, "ro");
- if (read_only)
- return streq(read_only, "1");
-
- return false;
-}
-
-bool enough_ram(void) {
- struct sysinfo si;
-
- assert_se(sysinfo(&si) >= 0);
-
- /* Enable readahead only with at least 128MB memory */
- return si.totalram > 127 * 1024*1024 / si.mem_unit;
-}
-
-static void mkdirs(void) {
- if (mkdir("/run/systemd", 0755) && errno != EEXIST)
- log_warning("Failed to create /run/systemd: %m");
- if (mkdir("/run/systemd/readahead", 0755) && errno != EEXIST)
- log_warning("Failed to create /run/systemd: %m");
-}
-
-int open_inotify(void) {
- int fd;
-
- fd = inotify_init1(IN_CLOEXEC|IN_NONBLOCK);
- if (fd < 0) {
- log_error("Failed to create inotify handle: %m");
- return -errno;
- }
-
- mkdirs();
-
- if (inotify_add_watch(fd, "/run/systemd/readahead", IN_CREATE) < 0) {
- log_error("Failed to watch /run/systemd/readahead: %m");
- safe_close(fd);
- return -errno;
- }
-
- return fd;
-}
-
-ReadaheadShared *shared_get(void) {
- _cleanup_close_ int fd = -1;
- ReadaheadShared *m = NULL;
-
- mkdirs();
-
- fd = open("/run/systemd/readahead/shared", O_CREAT|O_RDWR|O_CLOEXEC, 0644);
- if (fd < 0) {
- log_error("Failed to create shared memory segment: %m");
- return NULL;
- }
-
- if (ftruncate(fd, sizeof(ReadaheadShared)) < 0) {
- log_error("Failed to truncate shared memory segment: %m");
- return NULL;
- }
-
- m = mmap(NULL, sizeof(ReadaheadShared), PROT_WRITE|PROT_READ, MAP_SHARED, fd, 0);
- if (m == MAP_FAILED) {
- log_error("Failed to mmap shared memory segment: %m");
- return NULL;
- }
-
- return m;
-}
-
-/* We use 20K instead of the more human digestable 16K here. Why?
- Simply so that it is more unlikely that users end up picking this
- value too so that we can recognize better whether the user changed
- the value while we had it temporarily bumped. */
-#define BUMP_REQUEST_NR (20*1024u)
-
-int block_bump_request_nr(const char *p) {
- struct stat st;
- uint64_t u;
- char *ap = NULL, *line = NULL;
- int r;
- dev_t d;
-
- assert(p);
-
- if (stat(p, &st) < 0)
- return -errno;
-
- if (major(st.st_dev) == 0)
- return 0;
-
- d = st.st_dev;
- block_get_whole_disk(d, &d);
-
- if (asprintf(&ap, "/sys/dev/block/%u:%u/queue/nr_requests", major(d), minor(d)) < 0) {
- r= -ENOMEM;
- goto finish;
- }
-
- r = read_one_line_file(ap, &line);
- if (r < 0) {
- if (r == -ENOENT)
- r = 0;
- goto finish;
- }
-
- r = safe_atou64(line, &u);
- if (r >= 0 && u >= BUMP_REQUEST_NR) {
- r = 0;
- goto finish;
- }
-
- free(line);
- line = NULL;
-
- if (asprintf(&line, "%u", BUMP_REQUEST_NR) < 0) {
- r = -ENOMEM;
- goto finish;
- }
-
- r = write_string_file(ap, line);
- if (r < 0)
- goto finish;
-
- log_info("Bumped block_nr parameter of %u:%u to %u. This is a temporary hack and should be removed one day.", major(d), minor(d), BUMP_REQUEST_NR);
- r = 1;
-
-finish:
- free(ap);
- free(line);
-
- return r;
-}
-
-int block_get_readahead(const char *p, uint64_t *bytes) {
- struct stat st;
- char *ap = NULL, *line = NULL;
- int r;
- dev_t d;
- uint64_t u;
-
- assert(p);
- assert(bytes);
-
- if (stat(p, &st) < 0)
- return -errno;
-
- if (major(st.st_dev) == 0)
- return 0;
-
- d = st.st_dev;
- block_get_whole_disk(d, &d);
-
- if (asprintf(&ap, "/sys/dev/block/%u:%u/bdi/read_ahead_kb", major(d), minor(d)) < 0) {
- r = -ENOMEM;
- goto finish;
- }
-
- r = read_one_line_file(ap, &line);
- if (r < 0)
- goto finish;
-
- r = safe_atou64(line, &u);
- if (r < 0)
- goto finish;
-
- *bytes = u * 1024ULL;
-
-finish:
- free(ap);
- free(line);
-
- return r;
-}
-
-int block_set_readahead(const char *p, uint64_t bytes) {
- struct stat st;
- char *ap = NULL, *line = NULL;
- int r;
- dev_t d;
-
- assert(p);
- assert(bytes);
-
- if (stat(p, &st) < 0)
- return -errno;
-
- if (major(st.st_dev) == 0)
- return 0;
-
- d = st.st_dev;
- block_get_whole_disk(d, &d);
-
- if (asprintf(&ap, "/sys/dev/block/%u:%u/bdi/read_ahead_kb", major(d), minor(d)) < 0) {
- r = -ENOMEM;
- goto finish;
- }
-
- if (asprintf(&line, "%llu", bytes / 1024ULL) < 0) {
- r = -ENOMEM;
- goto finish;
- }
-
- r = write_string_file(ap, line);
- if (r < 0)
- goto finish;
-
-finish:
- free(ap);
- free(line);
-
- return r;
-}
~ianmdlvl / elogind.git / blobdiff