diff options
Diffstat (limited to 'src/readahead/readahead-common.c')
-rw-r--r-- | src/readahead/readahead-common.c | 398 |
1 files changed, 0 insertions, 398 deletions
diff --git a/src/readahead/readahead-common.c b/src/readahead/readahead-common.c deleted file mode 100644 index 3ca48a7257..0000000000 --- a/src/readahead/readahead-common.c +++ /dev/null @@ -1,398 +0,0 @@ -/*-*- 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; -} |