[systemd-commits] configure.ac .gitignore Makefile.am src/hashmap.c src/hashmap.h src/linux src/macro.h src/missing.h src/readahead-collect.c src/readahead-common.c src/readahead-common.h src/readahead-replay.c
Lennart Poettering
lennart at kemper.freedesktop.org
Thu Sep 23 06:02:29 PDT 2010
.gitignore | 2
Makefile.am | 28 ++-
configure.ac | 1
src/hashmap.c | 15 +
src/hashmap.h | 1
src/linux/fanotify.h | 98 ++++++++++
src/macro.h | 6
src/missing.h | 25 ++
src/readahead-collect.c | 437 ++++++++++++++++++++++++++++++++++++++++++++++++
src/readahead-common.c | 107 +++++++++++
src/readahead-common.h | 33 +++
src/readahead-replay.c | 214 +++++++++++++++++++++++
12 files changed, 966 insertions(+), 1 deletion(-)
New commits:
commit 22be093ffb403a1c474037939ca9b88b1ee39f77
Author: Lennart Poettering <lennart at poettering.net>
Date: Thu Sep 23 15:01:41 2010 +0200
readahead: implement minimal readahead logic based on fanotify(), mincore() and readahead()
diff --git a/.gitignore b/.gitignore
index 7cecf1c..b5fc8d7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
+systemd-readahead-collect
+systemd-readahead-replay
systemd-reply-password
systemd-ask-password-agent
systemd-ask-password
diff --git a/Makefile.am b/Makefile.am
index 0ac6b1a..2cd3deb 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -92,7 +92,9 @@ rootlibexec_PROGRAMS = \
systemd-remount-api-vfs \
systemd-kmsg-syslogd \
systemd-vconsole-setup \
- systemd-reply-password
+ systemd-reply-password \
+ systemd-readahead-collect \
+ systemd-readahead-replay
noinst_PROGRAMS = \
test-engine \
@@ -699,6 +701,30 @@ systemd_reply_password_SOURCES = \
systemd_reply_password_LDADD = \
libsystemd-basic.la
+systemd_readahead_collect_SOURCES = \
+ src/readahead-collect.c \
+ src/sd-daemon.c \
+ src/readahead-common.c
+
+systemd_readahead_collect_CFLAGS = \
+ $(UDEV_CFLAGS)
+
+systemd_readahead_collect_LDADD = \
+ libsystemd-basic.la \
+ $(UDEV_LIBS)
+
+systemd_readahead_replay_SOURCES = \
+ src/readahead-replay.c \
+ src/sd-daemon.c \
+ src/readahead-common.c
+
+systemd_readahead_replay_CFLAGS = \
+ $(UDEV_CFLAGS)
+
+systemd_readahead_replay_LDADD = \
+ libsystemd-basic.la \
+ $(UDEV_LIBS)
+
systemd_cgls_SOURCES = \
src/cgls.c \
src/cgroup-show.c \
diff --git a/configure.ac b/configure.ac
index e3c1fdd..da627a0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,6 +27,7 @@ AM_INIT_AUTOMAKE([foreign 1.11 -Wall -Wno-portability silent-rules tar-pax subdi
AC_SUBST(PACKAGE_URL, [http://www.freedesktop.org/wiki/Software/systemd])
AC_CANONICAL_HOST
+AC_DEFINE_UNQUOTED([CANONICAL_HOST], "$host", [Canonical host string.])
AM_SILENT_RULES([yes])
diff --git a/src/hashmap.c b/src/hashmap.c
index 51f0013..4b18705 100644
--- a/src/hashmap.c
+++ b/src/hashmap.c
@@ -476,6 +476,21 @@ void* hashmap_steal_first(Hashmap *h) {
return data;
}
+void* hashmap_steal_first_key(Hashmap *h) {
+ void *key;
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_head)
+ return NULL;
+
+ key = (void*) h->iterate_list_head->key;
+ remove_entry(h, h->iterate_list_head);
+
+ return key;
+}
+
unsigned hashmap_size(Hashmap *h) {
if (!h)
diff --git a/src/hashmap.h b/src/hashmap.h
index c48d6b3..ac5a8ae 100644
--- a/src/hashmap.h
+++ b/src/hashmap.h
@@ -72,6 +72,7 @@ void *hashmap_iterate_skip(Hashmap *h, const void *key, Iterator *i);
void hashmap_clear(Hashmap *h);
void *hashmap_steal_first(Hashmap *h);
+void *hashmap_steal_first_key(Hashmap *h);
void* hashmap_first(Hashmap *h);
void* hashmap_last(Hashmap *h);
diff --git a/src/linux/fanotify.h b/src/linux/fanotify.h
new file mode 100644
index 0000000..63531a6
--- /dev/null
+++ b/src/linux/fanotify.h
@@ -0,0 +1,98 @@
+#ifndef _LINUX_FANOTIFY_H
+#define _LINUX_FANOTIFY_H
+
+#include <linux/types.h>
+
+/* the following events that user-space can register for */
+#define FAN_ACCESS 0x00000001 /* File was accessed */
+#define FAN_MODIFY 0x00000002 /* File was modified */
+#define FAN_CLOSE_WRITE 0x00000008 /* Unwrittable file closed */
+#define FAN_CLOSE_NOWRITE 0x00000010 /* Writtable file closed */
+#define FAN_OPEN 0x00000020 /* File was opened */
+
+#define FAN_EVENT_ON_CHILD 0x08000000 /* interested in child events */
+
+/* FIXME currently Q's have no limit.... */
+#define FAN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
+
+#define FAN_OPEN_PERM 0x00010000 /* File open in perm check */
+#define FAN_ACCESS_PERM 0x00020000 /* File accessed in perm check */
+
+/* helper events */
+#define FAN_CLOSE (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
+
+/* flags used for fanotify_init() */
+#define FAN_CLOEXEC 0x00000001
+#define FAN_NONBLOCK 0x00000002
+
+#define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK)
+
+/* flags used for fanotify_modify_mark() */
+#define FAN_MARK_ADD 0x00000001
+#define FAN_MARK_REMOVE 0x00000002
+#define FAN_MARK_DONT_FOLLOW 0x00000004
+#define FAN_MARK_ONLYDIR 0x00000008
+#define FAN_MARK_MOUNT 0x00000010
+#define FAN_MARK_IGNORED_MASK 0x00000020
+#define FAN_MARK_IGNORED_SURV_MODIFY 0x00000040
+#define FAN_MARK_FLUSH 0x00000080
+
+#define FAN_ALL_MARK_FLAGS (FAN_MARK_ADD |\
+ FAN_MARK_REMOVE |\
+ FAN_MARK_DONT_FOLLOW |\
+ FAN_MARK_ONLYDIR |\
+ FAN_MARK_MOUNT |\
+ FAN_MARK_IGNORED_MASK |\
+ FAN_MARK_IGNORED_SURV_MODIFY)
+
+/*
+ * All of the events - we build the list by hand so that we can add flags in
+ * the future and not break backward compatibility. Apps will get only the
+ * events that they originally wanted. Be sure to add new events here!
+ */
+#define FAN_ALL_EVENTS (FAN_ACCESS |\
+ FAN_MODIFY |\
+ FAN_CLOSE |\
+ FAN_OPEN)
+
+/*
+ * All events which require a permission response from userspace
+ */
+#define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
+ FAN_ACCESS_PERM)
+
+#define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
+ FAN_ALL_PERM_EVENTS |\
+ FAN_Q_OVERFLOW)
+
+#define FANOTIFY_METADATA_VERSION 2
+
+struct fanotify_event_metadata {
+ __u32 event_len;
+ __u32 vers;
+ __u64 mask;
+ __s32 fd;
+ __s32 pid;
+} __attribute__ ((packed));
+
+struct fanotify_response {
+ __s32 fd;
+ __u32 response;
+} __attribute__ ((packed));
+
+/* Legit userspace responses to a _PERM event */
+#define FAN_ALLOW 0x01
+#define FAN_DENY 0x02
+
+/* Helper functions to deal with fanotify_event_metadata buffers */
+#define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
+
+#define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
+ (struct fanotify_event_metadata*)(((char *)(meta)) + \
+ (meta)->event_len))
+
+#define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
+ (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
+ (long)(meta)->event_len <= (long)(len))
+
+#endif /* _LINUX_FANOTIFY_H */
diff --git a/src/macro.h b/src/macro.h
index 44b4817..12ccbb1 100644
--- a/src/macro.h
+++ b/src/macro.h
@@ -27,6 +27,8 @@
#include <sys/uio.h>
#include <inttypes.h>
+#define PAGE_SIZE 4096
+
#define _printf_attr_(a,b) __attribute__ ((format (printf, a, b)))
#define _sentinel_ __attribute__ ((sentinel))
#define _noreturn_ __attribute__((noreturn))
@@ -49,6 +51,10 @@ static inline size_t ALIGN(size_t l) {
return ((l + sizeof(void*) - 1) & ~(sizeof(void*) - 1));
}
+static inline size_t PAGE_ALIGN(size_t l) {
+ return ((l + PAGE_SIZE - 1) & ~(PAGE_SIZE -1));
+}
+
#define ELEMENTSOF(x) (sizeof(x)/sizeof((x)[0]))
#define MAX(a,b) \
diff --git a/src/missing.h b/src/missing.h
index 418dbb8..defe885 100644
--- a/src/missing.h
+++ b/src/missing.h
@@ -76,4 +76,29 @@ static inline int pivot_root(const char *new_root, const char *put_old) {
return syscall(SYS_pivot_root, new_root, put_old);
}
+#ifdef __x86_64__
+#ifndef __NR_fanotify_init
+#define __NR_fanotify_init 300
+#endif
+#ifndef __NR_fanotify_mark
+#define __NR_fanotify_mark 301
+#endif
+#else
+#ifndef __NR_fanotify_init
+#define __NR_fanotify_init 338
+#endif
+#ifndef __NR_fanotify_mark
+#define __NR_fanotify_mark 339
+#endif
+#endif
+
+static inline int fanotify_init(unsigned int flags, unsigned int event_f_flags) {
+ return syscall(__NR_fanotify_init, flags, event_f_flags);
+}
+
+static inline int fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
+ int dfd, const char *pathname) {
+ return syscall(__NR_fanotify_mark, fanotify_fd, flags, mask, dfd, pathname);
+}
+
#endif
diff --git a/src/readahead-collect.c b/src/readahead-collect.c
new file mode 100644
index 0000000..93a0452
--- /dev/null
+++ b/src/readahead-collect.c
@@ -0,0 +1,437 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <inttypes.h>
+#include <fcntl.h>
+#include <linux/limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <linux/fanotify.h>
+#include <sys/signalfd.h>
+#include <sys/poll.h>
+#include <sys/mman.h>
+#include <linux/fs.h>
+#include <linux/fiemap.h>
+#include <sys/ioctl.h>
+
+#include "missing.h"
+#include "util.h"
+#include "set.h"
+#include "sd-daemon.h"
+#include "ioprio.h"
+#include "readahead-common.h"
+
+/*
+ fixme:
+
+ - BTRFS_IOC_DEFRAG
+*/
+
+#define MINCORE_VEC_SIZE (READAHEAD_FILE_SIZE_MAX/PAGE_SIZE)
+
+static int pack_file(FILE *pack, const char *fn) {
+ struct stat st;
+ void *start = MAP_FAILED;
+ uint8_t vec[MINCORE_VEC_SIZE];
+ uint32_t b, c;
+ size_t l, pages;
+ bool mapped;
+ int r = 0, fd = -1, k;
+
+ assert(pack);
+ assert(fn);
+
+ if ((fd = open(fn, O_RDONLY|O_CLOEXEC|O_NOATIME|O_NOCTTY|O_NOFOLLOW)) < 0) {
+ log_warning("open(%s) failed: %m", fn);
+ r = -errno;
+ goto finish;
+ }
+
+ if ((k = file_verify(fd, fn, &st)) <= 0) {
+ r = k;
+ goto finish;
+ }
+
+ l = PAGE_ALIGN(st.st_size);
+ if ((start = mmap(NULL, l, PROT_READ, MAP_SHARED, fd, 0)) == MAP_FAILED) {
+ log_warning("mmap(%s) failed: %m", fn);
+ r = -errno;
+ goto finish;
+ }
+
+ if (mincore(start, l, vec) < 0) {
+ log_warning("mincore(%s) failed: %m", fn);
+ r = -errno;
+ goto finish;
+ }
+
+ fputs(fn, pack);
+ fputc('\n', pack);
+
+ pages = l / PAGE_SIZE;
+ mapped = false;
+ for (c = 0; c < pages; c++) {
+ bool new_mapped = (vec[c] & 1);
+
+ if (!mapped && new_mapped)
+ b = c;
+ else if (mapped && !new_mapped) {
+ fwrite(&b, sizeof(b), 1, pack);
+ fwrite(&c, sizeof(c), 1, pack);
+
+ log_debug("%s: page %u to %u", fn, b, c);
+ }
+
+ mapped = new_mapped;
+ }
+
+ /* We don't write any range data if we should read the entire file */
+ if (mapped && b > 0) {
+ fwrite(&b, sizeof(b), 1, pack);
+ fwrite(&c, sizeof(c), 1, pack);
+
+ log_debug("%s: page %u to %u", fn, b, c);
+ }
+
+ /* End marker */
+ b = 0;
+ fwrite(&b, sizeof(b), 1, pack);
+ fwrite(&b, sizeof(b), 1, pack);
+
+finish:
+ if (start != MAP_FAILED)
+ munmap(start, l);
+
+ if (fd >= 0)
+ close_nointr_nofail(fd);
+
+ return r;
+}
+
+static unsigned long fd_first_block(int fd) {
+ struct {
+ struct fiemap fiemap;
+ struct fiemap_extent extent;
+ } data;
+
+ zero(data);
+ data.fiemap.fm_length = ~0ULL;
+ data.fiemap.fm_extent_count = 1;
+
+ if (ioctl(fd, FS_IOC_FIEMAP, &data) < 0)
+ return 0;
+
+ if (data.fiemap.fm_mapped_extents <= 0)
+ return 0;
+
+ if (data.fiemap.fm_extents[0].fe_flags & FIEMAP_EXTENT_UNKNOWN)
+ return 0;
+
+ return (unsigned long) data.fiemap.fm_extents[0].fe_physical;
+}
+
+struct item {
+ const char *path;
+ unsigned long block;
+};
+
+static int qsort_compare(const void *a, const void *b) {
+ const struct item *i, *j;
+
+ i = a;
+ j = b;
+
+ if (i->block < j->block)
+ return -1;
+ if (i->block > j->block)
+ return 1;
+
+ return strcmp(i->path, j->path);
+}
+
+static int collect(const char *root) {
+ enum {
+ FD_FANOTIFY,
+ FD_SIGNAL,
+ _FD_MAX
+ };
+ struct pollfd pollfd[_FD_MAX];
+ int fanotify_fd = -1, signal_fd = -1, r = 0;
+ pid_t my_pid;
+ Hashmap *files = NULL;
+ Iterator i;
+ char *p, *q;
+ sigset_t mask;
+ FILE *pack = NULL;
+ char *pack_fn_new = NULL, *pack_fn = NULL;
+ bool on_ssd;
+
+ assert(root);
+
+ if (ioprio_set(IOPRIO_WHO_PROCESS, getpid(), IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0)) < 0)
+ log_warning("Failed to set IDLE IO priority class: %m");
+
+ assert_se(sigemptyset(&mask) == 0);
+ sigset_add_many(&mask, SIGINT, SIGTERM, -1);
+ assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
+
+ if ((signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) {
+ log_error("signalfd(): %m");
+ r = -errno;
+ goto finish;
+ }
+
+ if (!(files = hashmap_new(string_hash_func, string_compare_func))) {
+ log_error("Failed to allocate set.");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ if ((fanotify_fd = fanotify_init(FAN_CLOEXEC, O_RDONLY|O_LARGEFILE|O_CLOEXEC|O_NOATIME)) < 0) {
+ log_error("Failed to create fanotify object: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ if (fanotify_mark(fanotify_fd, FAN_MARK_ADD|FAN_MARK_MOUNT, FAN_OPEN, AT_FDCWD, root) < 0) {
+ log_error("Failed to mark %s: %m", root);
+ r = -errno;
+ goto finish;
+ }
+
+ my_pid = getpid();
+
+ zero(pollfd);
+ pollfd[FD_FANOTIFY].fd = fanotify_fd;
+ pollfd[FD_FANOTIFY].events = POLLIN;
+ pollfd[FD_SIGNAL].fd = signal_fd;
+ pollfd[FD_SIGNAL].events = POLLIN;
+
+ sd_notify(0,
+ "READY=1\n"
+ "STATUS=Collecting readahead data");
+
+ log_debug("Collecting...");
+
+ for (;;) {
+ union {
+ struct fanotify_event_metadata metadata;
+ char buffer[4096];
+ } data;
+ ssize_t n;
+ struct fanotify_event_metadata *m;
+
+ if (poll(pollfd, _FD_MAX, -1) < 0) {
+
+ if (errno == EINTR)
+ continue;
+
+ log_error("poll(): %m");
+ r = -errno;
+ goto finish;
+ }
+
+ if (pollfd[FD_SIGNAL].revents != 0)
+ break;
+
+ if ((n = read(fanotify_fd, &data, sizeof(data))) < 0) {
+
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+
+ log_error("Failed to read event: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ m = &data.metadata;
+ while (FAN_EVENT_OK(m, n)) {
+
+ if (m->pid != my_pid && m->fd >= 0) {
+ char fn[PATH_MAX];
+ int k;
+
+ snprintf(fn, sizeof(fn), "/proc/self/fd/%i", m->fd);
+ char_array_0(fn);
+
+ if ((k = readlink_malloc(fn, &p)) >= 0) {
+
+ if (hashmap_get(files, p))
+ /* Already read */
+ free(p);
+ else {
+ unsigned long ul;
+
+ ul = fd_first_block(m->fd);
+
+ if ((k = hashmap_put(files, p, ULONG_TO_PTR(ul))) < 0) {
+
+ if (k != -EEXIST)
+ log_warning("set_put() failed: %s", strerror(-k));
+
+ free(p);
+ }
+ }
+
+ } else
+ log_warning("readlink(%s) failed: %s", fn, strerror(-k));
+ }
+
+ if (m->fd)
+ close_nointr_nofail(m->fd);
+
+ m = FAN_EVENT_NEXT(m, n);
+ }
+
+ }
+
+ if (fanotify_fd >= 0) {
+ close_nointr_nofail(fanotify_fd);
+ fanotify_fd = -1;
+ }
+
+ log_debug("Writing Pack File...");
+
+ on_ssd = fs_on_ssd(root);
+ log_debug("On SSD: %s", yes_no(on_ssd));
+
+ asprintf(&pack_fn, "%s/.readahead", root);
+ asprintf(&pack_fn_new, "%s/.readahead.new", root);
+
+ if (!pack_fn || !pack_fn_new) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ if (!(pack = fopen(pack_fn_new, "we"))) {
+ log_error("Failed to open pack file: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ fputs(CANONICAL_HOST "\n", pack);
+ putc(on_ssd ? 'S' : 'R', pack);
+
+ if (on_ssd) {
+
+ /* On SSD, just write things out in the order the
+ * files where accessed */
+
+ HASHMAP_FOREACH_KEY(q, p, files, i)
+ pack_file(pack, p);
+ } else {
+ struct item *ordered, *j;
+ unsigned k, n;
+
+ /* On rotating media, order things by the block
+ * numbers */
+
+ log_debug("Ordering...");
+
+ n = hashmap_size(files);
+ if (!(ordered = new(struct item, n))) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ j = ordered;
+ HASHMAP_FOREACH_KEY(q, p, files, i) {
+ j->path = p;
+ j->block = PTR_TO_ULONG(q);
+ j++;
+ }
+
+ assert(ordered + n == j);
+
+ qsort(ordered, n, sizeof(struct item), qsort_compare);
+
+ for (k = 0; k < n; k++)
+ pack_file(pack, ordered[k].path);
+
+ free(ordered);
+ }
+
+ log_debug("Finalizing...");
+
+ fflush(pack);
+
+ if (ferror(pack)) {
+ log_error("Failed to write pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ if (rename(pack_fn_new, pack_fn) < 0) {
+ log_error("Failed to rename readahead file: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ fclose(pack);
+ pack = NULL;
+
+ log_debug("Done.");
+
+finish:
+ if (fanotify_fd >= 0)
+ close_nointr_nofail(fanotify_fd);
+
+ if (signal_fd >= 0)
+ close_nointr_nofail(signal_fd);
+
+ if (pack) {
+ fclose(pack);
+ unlink(pack_fn_new);
+ }
+
+ free(pack_fn_new);
+ free(pack_fn);
+
+ while ((p = hashmap_steal_first_key(files)))
+ free(q);
+
+ hashmap_free(files);
+
+ return r;
+}
+
+int main(int argc, char *argv[]) {
+ /* log_set_target(LOG_TARGET_SYSLOG_OR_KMSG); */
+ log_parse_environment();
+ log_open();
+
+ log_set_max_level(LOG_DEBUG);
+
+ if (collect("/") < 0)
+ return 1;
+
+ return 0;
+}
diff --git a/src/readahead-common.c b/src/readahead-common.c
new file mode 100644
index 0000000..8533717
--- /dev/null
+++ b/src/readahead-common.c
@@ -0,0 +1,107 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <libudev.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "log.h"
+#include "readahead-common.h"
+#include "util.h"
+
+int file_verify(int fd, const char *fn, 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 > READAHEAD_FILE_SIZE_MAX) {
+ log_debug("Not preloading file %s with size out of bounds %zi", fn, st->st_size);
+ return 0;
+ }
+
+ return 1;
+}
+
+int fs_on_ssd(const char *p) {
+ struct stat st;
+ struct udev *udev = NULL;
+ struct udev_device *udev_device = NULL, *look_at = NULL;
+ bool b = false;
+ const char *devtype, *rotational, *model, *id;
+
+ assert(p);
+
+ if (stat(p, &st) < 0)
+ return -errno;
+
+ if (!(udev = udev_new()))
+ return -ENOMEM;
+
+ if (!(udev_device = udev_device_new_from_devnum(udev, 'b', st.st_dev)))
+ goto finish;
+
+ if ((devtype = udev_device_get_property_value(udev_device, "DEVTYPE")) &&
+ streq(devtype, "partition"))
+ look_at = udev_device_get_parent(udev_device);
+ else
+ look_at = udev_device;
+
+ if (!look_at)
+ goto finish;
+
+ /* First, try high-level property */
+ if ((id = udev_device_get_property_value(look_at, "ID_SSD"))) {
+ b = streq(id, "1");
+ goto finish;
+ }
+
+ /* Second, try kernel attribute */
+ if ((rotational = udev_device_get_sysattr_value(look_at, "queue/rotational")))
+ if ((b = streq(rotational, "0")))
+ goto finish;
+
+ /* Finally, fallback to heuristics */
+ if (!(look_at = udev_device_get_parent(look_at)))
+ goto finish;
+
+ if ((model = udev_device_get_sysattr_value(look_at, "model")))
+ b = !!strstr(model, "SSD");
+
+finish:
+ if (udev_device)
+ udev_device_unref(udev_device);
+
+ if (udev)
+ udev_unref(udev);
+
+ return b;
+}
diff --git a/src/readahead-common.h b/src/readahead-common.h
new file mode 100644
index 0000000..da6a74e
--- /dev/null
+++ b/src/readahead-common.h
@@ -0,0 +1,33 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef fooreadaheadcommonhfoo
+#define fooreadaheadcommonhfoo
+
+/***
+ 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/stat.h>
+
+#define READAHEAD_FILE_SIZE_MAX (128*1024*1024)
+
+int file_verify(int fd, const char *fn, struct stat *st);
+
+int fs_on_ssd(const char *p);
+
+#endif
diff --git a/src/readahead-replay.c b/src/readahead-replay.c
new file mode 100644
index 0000000..b886857
--- /dev/null
+++ b/src/readahead-replay.c
@@ -0,0 +1,214 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <inttypes.h>
+#include <fcntl.h>
+#include <linux/limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "missing.h"
+#include "util.h"
+#include "set.h"
+#include "sd-daemon.h"
+#include "ioprio.h"
+#include "readahead-common.h"
+
+static int unpack_file(FILE *pack) {
+ char fn[PATH_MAX];
+ int r = 0, fd = -1;
+ bool any = false;
+ struct stat st;
+
+ assert(pack);
+
+ if (!fgets(fn, sizeof(fn), pack))
+ return 0;
+
+ char_array_0(fn);
+ truncate_nl(fn);
+
+ if ((fd = open(fn, O_RDONLY|O_CLOEXEC|O_NOATIME|O_NOCTTY|O_NOFOLLOW)) < 0)
+ log_warning("open(%s) failed: %m", fn);
+ else if (file_verify(fd, fn, &st) <= 0) {
+ close_nointr_nofail(fd);
+ fd = -1;
+ }
+
+ for (;;) {
+ uint32_t b, c;
+
+ if (fread(&b, sizeof(b), 1, pack) != 1 ||
+ fread(&c, sizeof(c), 1, pack) != 1) {
+ log_error("Premature end of pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ if (b == 0 && c == 0)
+ break;
+
+ if (c <= b) {
+ log_error("Invalid pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ log_debug("%s: page %u to %u", fn, b, c);
+
+ any = true;
+
+ if (fd >= 0)
+ if (readahead(fd, b * PAGE_SIZE, (c - b) * PAGE_SIZE) < 0) {
+ log_warning("readahead() failed: %m");
+ goto finish;
+ }
+ }
+
+ if (!any && fd >= 0) {
+ /* if no range is encoded in the pack file this is
+ * intended to mean that the whole file shall be
+ * read */
+
+ if (readahead(fd, 0, st.st_size) < 0) {
+ log_warning("readahead() failed: %m");
+ goto finish;
+ }
+ }
+
+finish:
+ if (fd >= 0)
+ close_nointr_nofail(fd);
+
+ return r;
+}
+
+static int replay(const char *root) {
+ FILE *pack;
+ char line[LINE_MAX];
+ int r = 0;
+ char *pack_fn = NULL, c;
+ bool on_ssd;
+ int prio;
+
+ assert(root);
+
+ if (asprintf(&pack_fn, "%s/.readahead", root) < 0) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ if ((!(pack = fopen(pack_fn, "re")))) {
+ if (errno == -ENOENT)
+ log_debug("No pack file found.");
+ else {
+ log_error("Failed to open pack file: %m");
+ r = -errno;
+ }
+
+ goto finish;
+ }
+
+ if (!(fgets(line, sizeof(line), pack))) {
+ log_error("Premature end of pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ char_array_0(line);
+
+ if (!streq(line, CANONICAL_HOST "\n")) {
+ log_debug("Pack file host type mismatch.");
+ goto finish;
+ }
+
+ if ((c = getc(pack)) == EOF) {
+ log_debug("Premature end of pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ /* We do not retest SSD here, so that we can start replaying
+ * before udev is up.*/
+ on_ssd = c == 'S';
+ log_debug("On SSD: %s", yes_no(on_ssd));
+
+ if (on_ssd)
+ prio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0);
+ else
+ prio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_RT, 7);
+
+ if (ioprio_set(IOPRIO_WHO_PROCESS, getpid(), prio) < 0)
+ log_warning("Failed to set IDLE IO priority class: %m");
+
+ sd_notify(0,
+ "READY=1\n"
+ "STATUS=Replaying readahead data");
+
+ log_debug("Replaying...");
+
+ while (!feof(pack) && !ferror(pack)) {
+ int k;
+
+ if ((k = unpack_file(pack)) < 0) {
+ r = k;
+ goto finish;
+ }
+ }
+
+ if (ferror(pack)) {
+ log_error("Failed to read pack file.");
+ r = -EIO;
+ goto finish;
+ }
+
+ log_debug("Done.");
+
+finish:
+ if (pack)
+ fclose(pack);
+
+ free(pack_fn);
+
+ return r;
+}
+
+int main(int argc, char*argv[]) {
+ /* log_set_target(LOG_TARGET_SYSLOG_OR_KMSG); */
+ log_parse_environment();
+ log_open();
+
+ log_set_max_level(LOG_DEBUG);
+
+ if (replay("/") < 0)
+ return 1;
+
+ return 0;
+}
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