| Message ID | e331c5f1485b7d9fa1278fb205a223af3a18366e.1725481837.git.josef@toxicpanda.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fstests: add two tests for the precontent fanotify work | expand |
On Wed, Sep 4, 2024 at 10:33 PM Josef Bacik <josef@toxicpanda.com> wrote: > > This is a test to validate the precontent hooks work properly for reads > and page faults. > > Signed-off-by: Josef Bacik <josef@toxicpanda.com> Very cool! Some minor comments below. I will publicly commit to duplicating your test to LTP in the hope of shaming myself to actually do it... > --- > doc/group-names.txt | 1 + > src/Makefile | 2 +- > src/precontent/Makefile | 26 ++ > src/precontent/mmap-validate.c | 227 +++++++++++++++++ > src/precontent/populate.c | 188 ++++++++++++++ > src/precontent/remote-fetch.c | 441 +++++++++++++++++++++++++++++++++ > tests/generic/800 | 68 +++++ > tests/generic/800.out | 2 + > 8 files changed, 954 insertions(+), 1 deletion(-) > create mode 100644 src/precontent/Makefile > create mode 100644 src/precontent/mmap-validate.c > create mode 100644 src/precontent/populate.c > create mode 100644 src/precontent/remote-fetch.c > create mode 100644 tests/generic/800 > create mode 100644 tests/generic/800.out > > diff --git a/doc/group-names.txt b/doc/group-names.txt > index 6cf71796..93ba6a23 100644 > --- a/doc/group-names.txt > +++ b/doc/group-names.txt > @@ -56,6 +56,7 @@ fiexchange XFS_IOC_EXCHANGE_RANGE ioctl > freeze filesystem freeze tests > fsck general fsck tests > fsmap FS_IOC_GETFSMAP ioctl > +fsnotify fsnotify tests > fsr XFS free space reorganizer > fuzzers filesystem fuzz tests > growfs increasing the size of a filesystem > diff --git a/src/Makefile b/src/Makefile > index 559209be..6dae892e 100644 > --- a/src/Makefile > +++ b/src/Makefile > @@ -40,7 +40,7 @@ EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \ > btrfs_crc32c_forged_name.py popdir.pl popattr.py \ > soak_duration.awk > > -SUBDIRS = log-writes perf > +SUBDIRS = log-writes perf precontent > > LLDLIBS = $(LIBHANDLE) $(LIBACL) -lpthread -lrt -luuid > > diff --git a/src/precontent/Makefile b/src/precontent/Makefile > new file mode 100644 > index 00000000..367a34bb > --- /dev/null > +++ b/src/precontent/Makefile > @@ -0,0 +1,26 @@ > +# SPDX-License-Identifier: GPL-2.0 > + > +TOPDIR = ../.. > +include $(TOPDIR)/include/builddefs > + > +TARGETS = $(basename $(wildcard *.c)) > + > +CFILES = $(TARGETS:=.c) > +LDIRT = $(TARGETS) > + > +default: depend $(TARGETS) > + > +depend: .dep > + > +include $(BUILDRULES) > + > +$(TARGETS): $(CFILES) > + @echo " [CC] $@" > + $(Q)$(LTLINK) $@.c -o $@ $(CFLAGS) $(LDFLAGS) $(LDLIBS) > + > +install: > + $(INSTALL) -m 755 -d $(PKG_LIB_DIR)/src/precontent > + $(INSTALL) -m 755 $(TARGETS) $(PKG_LIB_DIR)/src/precontent > + > +-include .dep > + > diff --git a/src/precontent/mmap-validate.c b/src/precontent/mmap-validate.c > new file mode 100644 > index 00000000..af606d5b > --- /dev/null > +++ b/src/precontent/mmap-validate.c > @@ -0,0 +1,227 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#define _FILE_OFFSET_BITS 64 > +#include <errno.h> > +#include <fcntl.h> > +#include <stdio.h> > +#include <stdlib.h> > +#include <string.h> > +#include <sys/mman.h> > +#include <unistd.h> > + > +/* 1 MiB. */ > +#define FILE_SIZE (1 * 1024 * 1024) > +#define PAGE_SIZE 4096 > + > +#define __free(func) __attribute__((cleanup(func))) > + > +static void freep(void *ptr) > +{ > + void *real_ptr = *(void **)ptr; > + if (real_ptr == NULL) > + return; > + free(real_ptr); > +} > + > +static void close_fd(int *fd) > +{ > + if (*fd < 0) > + return; > + close(*fd); > +} > + > +static void unmap(void *ptr) > +{ > + void *real_ptr = *(void **)ptr; > + if (real_ptr == NULL) > + return; > + munmap(real_ptr, PAGE_SIZE); > +} > + > +static void print_buffer(const char *buf, off_t buf_off, off_t off, size_t len) > +{ > + for (int i = 0; i <= (len / 32); i++) { > + printf("%lu:", off + (i * 32)); > + > + for (int c = 0; c < 32; c++) { > + if (!(c % 8)) > + printf(" "); > + printf("%c", buf[buf_off++]); > + } > + printf("\n"); > + } > +} > + > +static int validate_buffer(const char *type, const char *buf, > + const char *pattern, off_t bufoff, off_t off, > + size_t len) > +{ > + > + if (memcmp(buf + bufoff, pattern + off, len)) { > + printf("Buffers do not match at off %lu size %lu after %s\n", > + off, len, type); > + printf("read buffer\n"); > + print_buffer(buf, bufoff, off, len); > + printf("valid buffer\n"); > + print_buffer(pattern, off, off, len); > + return 1; > + } > + > + return 0; > +} > + > +static int validate_range_fd(int fd, char *pattern, off_t off, size_t len) > +{ > + char *buf __free(freep) = NULL; > + ssize_t ret; > + size_t readin = 0; > + > + buf = malloc(len); > + if (!buf) { > + perror("malloc buf"); > + return 1; > + } > + > + while ((ret = pread(fd, buf + readin, len - readin, off + readin)) > 0) { > + readin += ret; > + if (readin == len) > + break; > + } > + > + if (ret < 0) { > + perror("read"); > + return 1; > + } > + > + return validate_buffer("read", buf, pattern, 0, off, len); > +} > + > +static int validate_file(const char *file, char *pattern) > +{ > + int fd __free(close_fd) = -EBADF; > + char *buf __free(unmap) = NULL; > + int ret; > + > + fd = open(file, O_RDONLY); > + if (fd < 0) { > + perror("open file"); > + return 1; > + } > + > + /* Cycle through the file and do some random reads and validate them. */ > + for (int i = 0; i < 5; i++) { > + off_t off = random() % FILE_SIZE; > + size_t len = random() % PAGE_SIZE; > + > + while ((off + len) > FILE_SIZE) { > + len = FILE_SIZE - off; > + if (len) > + break; > + len = random() % PAGE_SIZE; > + } > + > + ret = validate_range_fd(fd, pattern, off, len); > + if (ret) > + return ret; > + } > + > + buf = mmap(NULL, FILE_SIZE, PROT_READ|PROT_EXEC, MAP_PRIVATE, fd, 0); > + if (!buf) { > + perror("mmap"); > + return 1; > + } > + > + /* Validate random ranges of the mmap buffer. */ > + for (int i = 0; i < 5; i++) { > + off_t off = random() % FILE_SIZE; > + size_t len = random() % PAGE_SIZE; > + > + while ((off + len) > FILE_SIZE) { > + len = FILE_SIZE - off; > + if (len) > + break; > + len = random() % PAGE_SIZE; > + } > + > + ret = validate_buffer("mmap", buf, pattern, off, off, len); > + if (ret) > + return ret; > + } > + > + /* Now check the whole thing, one page at a time. */ > + for (int i = 0; i < (FILE_SIZE / PAGE_SIZE); i++) { > + ret = validate_buffer("mmap", buf, pattern, i * PAGE_SIZE, > + i * PAGE_SIZE, PAGE_SIZE); > + if (ret) > + return ret; > + } > + > + return 0; > +} > + > +static int create_file(const char *file, char *pattern) > +{ > + ssize_t ret; > + size_t written = 0; > + int fd __free(close_fd) = -EBADF; > + > + fd = open(file, O_RDWR | O_CREAT, 0644); > + if (fd < 0) { > + perror("opening file"); > + return 1; > + } > + > + while ((ret = write(fd, pattern + written, FILE_SIZE - written)) > 0) { > + written += ret; > + if (written == FILE_SIZE) > + break; > + } > + > + if (ret < 0) { > + perror("writing to the file"); > + return 1; > + } > + > + return 0; > +} > + > +static void generate_pattern(char *pattern) > +{ > + for (int i = 0; i < (FILE_SIZE / PAGE_SIZE); i++) { > + char fill = 'a' + (i % 26); > + > + memset(pattern + (i * PAGE_SIZE), fill, PAGE_SIZE); > + } > +} > + > +static void usage(void) > +{ > + fprintf(stderr, "Usage: mmap-validate <create|validate> <file>\n"); > +} > + > +int main(int argc, char **argv) > +{ > + char *pattern __free(freep) = NULL; > + > + if (argc != 3) { > + usage(); > + return 1; > + } > + > + pattern = malloc(FILE_SIZE * sizeof(char)); > + if (!pattern) { > + perror("malloc pattern"); > + return 1; > + } > + > + generate_pattern(pattern); > + > + if (!strcmp(argv[1], "create")) > + return create_file(argv[2], pattern); > + > + if (strcmp(argv[1], "validate")) { > + usage(); > + return 1; > + } > + > + return validate_file(argv[2], pattern); > +} > diff --git a/src/precontent/populate.c b/src/precontent/populate.c > new file mode 100644 > index 00000000..9c935427 > --- /dev/null > +++ b/src/precontent/populate.c > @@ -0,0 +1,188 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#define _FILE_OFFSET_BITS 64 > +#include <dirent.h> > +#include <errno.h> > +#include <fcntl.h> > +#include <limits.h> > +#include <poll.h> > +#include <stdio.h> > +#include <stdlib.h> > +#include <string.h> > +#include <sys/stat.h> > +#include <unistd.h> > + > +#define __free(func) __attribute__((cleanup(func))) > + > +static void close_fd(int *fd) > +{ > + if (*fd < 0) > + return; > + close(*fd); > +} > + > +static void close_dir(DIR **dir) > +{ > + if (*dir == NULL) > + return; > + closedir(*dir); > +} > + > +static void freep(void *ptr) > +{ > + void *real_ptr = *(void **)ptr; > + if (real_ptr == NULL) > + return; > + free(real_ptr); > +} > + > +/* > + * Dup a path, make sure there's a trailing '/' to make path concat easier. > + */ > +static char *pathdup(const char *orig) > +{ > + char *ret; > + size_t len = strlen(orig); > + > + /* Easy path, we have a trailing '/'. */ > + if (orig[len - 1] == '/') > + return strdup(orig); > + > + ret = malloc((len + 2) * sizeof(char)); > + if (!ret) > + return ret; > + > + memcpy(ret, orig, len); > + ret[len] = '/'; > + len++; > + ret[len] = '\0'; > + return ret; > +} > + > +static int process_directory(DIR *srcdir, char *srcpath, char *dstpath) > +{ > + char *src __free(freep) = NULL; > + char *dst __free(freep) = NULL; > + size_t srclen = strlen(srcpath) + 256; > + size_t dstlen = strlen(dstpath) + 256; > + struct dirent *dirent; > + > + src = malloc(srclen * sizeof(char)); > + dst = malloc(dstlen * sizeof(char)); > + if (!src || !dst) { > + perror("allocating path buf"); > + return -1; > + } > + > + errno = 0; > + while ((dirent = readdir(srcdir)) != NULL) { > + if (!strcmp(dirent->d_name, ".") || > + !strcmp(dirent->d_name, "..")) > + continue; > + > + if (dirent->d_type == DT_DIR) { > + DIR *nextdir __free(close_dir) = NULL; > + struct stat st; > + int ret; > + > + snprintf(src, srclen, "%s%s/", srcpath, dirent->d_name); > + snprintf(dst, dstlen, "%s%s/", dstpath, dirent->d_name); > + > + nextdir = opendir(src); > + if (!nextdir) { > + fprintf(stderr, "Couldn't open directory %s: %s (%d)\n", > + src, strerror(errno), errno); > + return -1; > + } > + > + if (stat(src, &st)) { > + fprintf(stderr, "Couldn't stat directory %s: %s (%d)\n", > + src, strerror(errno), errno); > + return -1; > + } > + > + if (mkdir(dst, st.st_mode)) { > + fprintf(stderr, "Couldn't mkdir %s: %s (%d)\n", > + dst, strerror(errno), errno); > + return -1; > + } > + > + ret = process_directory(nextdir, src, dst); > + if (ret) > + return ret; > + } else if (dirent->d_type == DT_REG) { > + int fd __free(close_fd) = -EBADF; > + struct stat st; > + > + snprintf(src, srclen, "%s%s", srcpath, dirent->d_name); > + snprintf(dst, dstlen, "%s%s", dstpath, dirent->d_name); > + > + if (stat(src, &st)) { > + fprintf(stderr, "Couldn't stat file %s: %s (%d)\n", > + src, strerror(errno), errno); > + return -1; > + } > + > + fd = open(dst, O_WRONLY|O_CREAT, st.st_mode); > + if (fd < 0) { > + fprintf(stderr, "Couldn't create file %s: %s (%d)\n", > + dst, strerror(errno), errno); > + return -1; > + } > + > + if (truncate(dst, st.st_size)) { > + fprintf(stderr, "Couldn't truncate file %s: %s (%d)\n", > + dst, strerror(errno), errno); > + return -1; > + } > + > + > + if (fsync(fd)) { > + fprintf(stderr, "Couldn't fsync file %s: %s (%d)\n", > + dst, strerror(errno), errno); > + return -1; > + } > + > + if (posix_fadvise(fd, 0, 0, POSIX_FADV_DONTNEED)) { > + fprintf(stderr, "Couldn't clear cache on file %s: %s (%d)\n", > + dst, strerror(errno), errno); > + return -1; > + } > + } > + errno = 0; > + } > + > + if (errno) { > + perror("readdir"); > + return -1; > + } > + return 0; > +} > + > +int main(int argc, char **argv) > +{ > + DIR *srcdir __free(close_dir) = NULL; > + char *dstpath __free(freep) = NULL; > + char *srcpath __free(freep) = NULL; > + int ret; > + > + if (argc != 3) { > + fprintf(stderr, "Usage: populate <src directory> <dest directory>\n"); > + return 1; > + } > + > + srcpath = pathdup(argv[1]); > + dstpath = pathdup(argv[2]); > + if (!dstpath || !srcpath) { > + perror("allocating paths"); > + return 1; > + } > + > + srcdir = opendir(srcpath); > + if (!srcdir) { > + perror("open src directory"); > + return 1; > + } > + > + ret = process_directory(srcdir, srcpath, dstpath); > + return ret ? 1 : 0; > +} > diff --git a/src/precontent/remote-fetch.c b/src/precontent/remote-fetch.c > new file mode 100644 > index 00000000..2e35b9f8 > --- /dev/null > +++ b/src/precontent/remote-fetch.c > @@ -0,0 +1,441 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#define _FILE_OFFSET_BITS 64 > +#include <dirent.h> > +#include <errno.h> > +#include <fcntl.h> > +#include <limits.h> > +#include <poll.h> > +#include <stdbool.h> > +#include <stdio.h> > +#include <stdlib.h> > +#include <string.h> > +#include <sys/fanotify.h> > +#include <sys/sendfile.h> > +#include <sys/stat.h> > +#include <unistd.h> > + > +#ifndef FAN_ERRNO_BITS > +#define FAN_ERRNO_BITS 8 > +#define FAN_ERRNO_SHIFT (32 - FAN_ERRNO_BITS) > +#define FAN_ERRNO_MASK ((1 << FAN_ERRNO_BITS) - 1) > +#define FAN_DENY_ERRNO(err) \ > + (FAN_DENY | ((((__u32)(err)) & FAN_ERRNO_MASK) << FAN_ERRNO_SHIFT)) > +#endif > + > +#ifndef FAN_PRE_ACCESS > +#define FAN_PRE_ACCESS 0x00080000 > +#endif > + > +#ifndef FAN_PRE_MODIFY > +#define FAN_PRE_MODIFY 0x00100000 > +#endif > + > +#ifndef FAN_EVENT_INFO_TYPE_RANGE > +#define FAN_EVENT_INFO_TYPE_RANGE 6 > +struct fanotify_event_info_range { > + struct fanotify_event_info_header hdr; > + __u32 pad; > + __u64 offset; > + __u64 count; > +}; > +#endif > + > +#define FAN_EVENTS (FAN_PRE_ACCESS | FAN_PRE_MODIFY) > + > +#define __round_mask(x, y) ((__typeof__(x))((y)-1)) > +#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) > +#define round_down(x, y) ((x) & ~__round_mask(x, y)) > + > +static const char *srcpath; > +static const char *dstpath; > +static int pagesize; > +static bool use_sendfile = false; > + > +#define __free(func) __attribute__((cleanup(func))) > + > +static void close_dir(DIR **dir) > +{ > + if (*dir == NULL) > + return; > + closedir(*dir); > +} > + > +static void close_fd(int *fd) > +{ > + if (*fd < 0) > + return; > + close(*fd); > +} > + > +static void freep(void *ptr) > +{ > + void *real_ptr = *(void **)ptr; > + if (real_ptr == NULL) > + return; > + free(real_ptr); > +} > + > +static int strip_dstpath(char *path) > +{ > + size_t remaining; > + > + if (strlen(path) <= strlen(dstpath)) { > + fprintf(stderr, "'%s' not in the path '%s'", path, dstpath); > + return -1; > + } > + > + if (strncmp(path, dstpath, strlen(dstpath))) { > + fprintf(stderr, "path '%s' doesn't start with the source path '%s'\n", > + path, dstpath); > + return -1; > + } > + > + remaining = strlen(path) - strlen(dstpath); > + memmove(path, path + strlen(dstpath), remaining); > + > + /* strip any leading / in order to make it easier to concat. */ > + while (*path == '/') { > + if (remaining == 0) { > + fprintf(stderr, "you gave us a weird ass string\n"); > + return -1; > + } > + remaining--; > + memmove(path, path + 1, remaining); > + } > + path[remaining] = '\0'; > + return 0; > +} > + > +/* > + * Dup a path, make sure there's a trailing '/' to make path concat easier. > + */ > +static char *pathdup(const char *orig) > +{ > + char *ret; > + size_t len = strlen(orig); > + > + /* Easy path, we have a trailing '/'. */ > + if (orig[len - 1] == '/') > + return strdup(orig); > + > + ret = malloc((len + 2) * sizeof(char)); > + if (!ret) > + return ret; > + > + memcpy(ret, orig, len); > + ret[len] = '/'; > + len++; > + ret[len] = '\0'; > + return ret; > +} > + > +static char *get_relpath(int fd) > +{ > + char procfd_path[PATH_MAX]; > + char abspath[PATH_MAX]; > + ssize_t path_len; > + int ret; > + > + /* readlink doesn't NULL terminate. */ > + memset(abspath, 0, sizeof(abspath)); > + > + snprintf(procfd_path, sizeof(procfd_path), "/proc/self/fd/%d", fd); > + path_len = readlink(procfd_path, abspath, sizeof(abspath) - 1); > + if (path_len < 0) { > + perror("readlink"); > + return NULL; > + } > + > + ret = strip_dstpath(abspath); > + if (ret < 0) > + return NULL; > + > + return strdup(abspath); > +} > + > +static int copy_range(int src_fd, int fd, off_t offset, size_t count) > +{ > + off_t src_offset = offset; > + ssize_t copied; > + > + if (use_sendfile) > + goto slow; > + > + while ((copied = copy_file_range(src_fd, &src_offset, fd, &offset, > + count, 0)) >= 0) { > + if (copied == 0) > + return 0; > + > + count -= copied; > + if (count == 0) > + return 0; > + } > + > + if (errno != EXDEV) { > + perror("copy_file_range"); > + return -1; > + } > + use_sendfile = true; > + > +slow: > + /* I love linux interfaces. */ > + if (lseek(fd, offset, SEEK_SET) == (off_t)-1) { > + perror("seeking"); > + return -1; > + } > + > + while ((copied = sendfile(fd, src_fd, &src_offset, count)) >= 0) { > + if (copied == 0) > + return 0; > + > + count -= copied; > + if (count == 0) > + return 0; > + } > + > + perror("sendfile"); > + return -1; > +} > + > +static int handle_event(int fanotify_fd, int fd, off_t offset, size_t count) > +{ > + char path[PATH_MAX]; > + char *relpath __free(freep) = NULL; > + int src_fd __free(close_fd) = -1; > + off_t end = offset + count; > + blkcnt_t src_blocks; > + struct stat st; > + > + relpath = get_relpath(fd); > + if (!relpath) > + return -1; > + > + offset = round_down(offset, pagesize); > + end = round_up(end, pagesize); > + count = end - offset; > + > + snprintf(path, sizeof(path), "%s%s", srcpath, relpath); > + src_fd = open(path, O_RDONLY); > + if (src_fd < 0) { > + fprintf(stderr, "srcpath %s relpath %s\n", srcpath, relpath); > + fprintf(stderr, "error opening file %s: %s (%d)\n", path, strerror(errno), errno); > + return -1; > + } > + > + if (fstat(src_fd, &st)) { > + perror("src fd is fucked"); > + return -1; > + } > + > + src_blocks = st.st_blocks; > + > + if (fstat(fd, &st)) { > + perror("fd is fucked"); > + return -1; > + } > + > + /* > + * If we are the same size or larger (which can happen if we copy zero's > + * instead of inserting a hole) then just assume we're full. This is > + * approximation can fall over, but its good enough for a PoC. > + */ > + if (st.st_blocks >= src_blocks) { > + int ret; > + > + snprintf(path, sizeof(path), "%s%s", dstpath, relpath); > + ret = fanotify_mark(fanotify_fd, FAN_MARK_REMOVE, > + FAN_EVENTS, -1, path); > + if (ret < 0) { > + /* We already removed the mark, carry on. */ > + if (errno == ENOENT) { > + errno = 0; > + return 0; > + } > + perror("removing fanotify mark"); > + return -1; > + } > + return 0; > + } > + > + > + return copy_range(src_fd, fd, offset, count); > +} > + > +static int handle_events(int fd) > +{ > + const struct fanotify_event_metadata *metadata; > + struct fanotify_event_metadata buf[200]; > + ssize_t len; > + struct fanotify_response response; > + int ret = 0; > + > + len = read(fd, (void *)buf, sizeof(buf)); > + if (len <= 0 && errno != EINTR) { > + perror("reading fanotify events"); > + return -1; > + } > + > + metadata = buf; > + while(FAN_EVENT_OK(metadata, len)) { > + off_t offset = 0; > + size_t count = 0; > + > + if (metadata->vers != FANOTIFY_METADATA_VERSION) { > + fprintf(stderr, "invalid metadata version, have %d, expect %d\n", > + metadata->vers, FANOTIFY_METADATA_VERSION); > + return -1; > + } > + if (metadata->fd < 0) { > + fprintf(stderr, "metadata fd is an error\n"); > + return -1; > + } > + if (!(metadata->mask & FAN_EVENTS)) { > + fprintf(stderr, "metadata mask incorrect %llu\n", > + metadata->mask); > + return -1; > + } > + > + /* > + * We have a specific range, load that instead of filling the > + * entire file in. > + */ > + if (metadata->event_len > FAN_EVENT_METADATA_LEN) { > + const struct fanotify_event_info_range *range; > + range = (const struct fanotify_event_info_range *)(metadata + 1); > + if (range->hdr.info_type == FAN_EVENT_INFO_TYPE_RANGE) { > + count = range->count; > + offset = range->offset; > + if (count == 0) { > + ret = 0; > + goto next; > + } > + } > + } > + > + /* We don't have a range, pre-fill the whole file. */ > + if (count == 0) { > + struct stat st; > + > + if (fstat(metadata->fd, &st)) { > + perror("stat() on opened file"); > + return -1; > + } > + > + count = st.st_size; > + } > + > + ret = handle_event(fd, metadata->fd, offset, count); > +next: > + response.fd = metadata->fd; > + if (ret) > + response.response = FAN_DENY_ERRNO(errno); > + else > + response.response = FAN_ALLOW; > + write(fd, &response, sizeof(response)); This write() can fail if errno is not on the white list. If you ignore this failure, the pre-content event will block. > + close(metadata->fd); > + metadata = FAN_EVENT_NEXT(metadata, len); > + } > + > + return ret; > +} > + > +static int add_marks(const char *src, int fanotify_fd) > +{ > + char *path __free(freep) = NULL; > + DIR *dir __free(close_dir) = NULL; > + size_t pathlen = strlen(src) + 256; > + struct dirent *dirent; > + > + path = malloc(pathlen * sizeof(char)); > + if (!path) { > + perror("allocating path buf"); > + return -1; > + } > + > + dir = opendir(src); > + if (!dir) { > + fprintf(stderr, "Couldn't open directory %s: %s (%d)\n", > + src, strerror(errno), errno); > + return -1; > + } > + > + errno = 0; > + while ((dirent = readdir(dir)) != NULL) { > + int ret; > + > + if (!strcmp(dirent->d_name, ".") || > + !strcmp(dirent->d_name, "..")) > + continue; > + > + if (dirent->d_type == DT_DIR) { > + snprintf(path, pathlen, "%s%s/", src, dirent->d_name); > + ret = add_marks(path, fanotify_fd); > + if (ret) > + return ret; > + } else if (dirent->d_type == DT_REG) { > + ret = fanotify_mark(fanotify_fd, FAN_MARK_ADD, > + FAN_EVENTS, dirfd(dir), > + dirent->d_name); > + if (ret < 0) { > + perror("fanotify_mark"); > + return -1; > + } > + } > + errno = 0; > + } > + return 0; > +} > + > +static void usage(void) > +{ > + fprintf(stderr, "Usage: remote-fetch <src directory> <dest directory>\n"); > +} > + > +int main(int argc, char **argv) > +{ > + int fd __free(close_fd) = -1; > + int dirfd __free(close_fd) = -1; > + int ret; > + > + if (argc != 3) { > + usage(); > + return 1; > + } > + > + pagesize = sysconf(_SC_PAGESIZE); > + if (pagesize < 0) { > + perror("sysconf"); > + return 1; > + } > + > + srcpath = pathdup(argv[1]); > + dstpath = pathdup(argv[2]); > + if (!srcpath || !dstpath) { > + perror("allocate paths"); > + return 1; > + } > + > + dirfd = open(dstpath, O_DIRECTORY | O_RDONLY); > + if (dirfd < 0) { > + perror("open dstpath"); > + return 1; > + } > + > + fd = fanotify_init(FAN_CLASS_PRE_CONTENT | FAN_UNLIMITED_MARKS, O_WRONLY | O_LARGEFILE); > + if (fd < 0) { > + perror("fanotify_init"); > + return 1; > + } > + > + ret = add_marks(dstpath, fd); > + if (ret < 0) > + return 1; > + > + for (;;) { > + ret = handle_events(fd); > + if (ret) > + break; > + } > + > + return (ret < 0) ? 1 : 0; > +} > diff --git a/tests/generic/800 b/tests/generic/800 > new file mode 100644 > index 00000000..08ac5b26 > --- /dev/null > +++ b/tests/generic/800 > @@ -0,0 +1,68 @@ > +#! /bin/bash > +# SPDX-License-Identifier: GPL-2.0 > +# Copyright (c) 2024 Meta Platforms, Inc. All Rights Reserved. > +# > +# FS QA Test 800 > +# > +# Validate the pre-content related fanotify features > +# > +# The mmap-verify pre-content tool generates a file and then validates that the > +# pre-content watched directory properly fills it in with a mixture of page > +# faults and normal reads. > +# > +. ./common/preamble > +_begin_fstest quick auto fsnotify > + > +_cleanup() > +{ > + cd / > + rm -rf $TEST_DIR/dst-$seq > + rm -rf $TEST_DIR/src-$seq > +} > + > +# real QA test starts here > +_supported_fs generic > +_require_test > +_require_test_program "precontent/mmap-validate" > +_require_test_program "precontent/populate" > +_require_test_program "precontent/remote-fetch" > + > +dstdir=$TEST_DIR/dst-$seq > +srcdir=$TEST_DIR/src-$seq > + > +POPULATE=$here/src/precontent/populate > +REMOTE_FETCH=$here/src/precontent/remote-fetch > +MMAP_VALIDATE=$here/src/precontent/mmap-validate > + > +mkdir $dstdir $srcdir For tests on the test partition, should also cleanup prior leftovers at the beginning of the test. > + > +# Generate the test file > +$MMAP_VALIDATE create $srcdir/validate > + > +# Generate the stub file in the watch directory > +$POPULATE $srcdir $dstdir > + > +# Start the remote watcher > +$REMOTE_FETCH $srcdir $dstdir & > + > +FETCH_PID=$! > + > +# We may not support fanotify, give it a second to start and then make sure the > +# fetcher is running before we try to validate the buffer > +sleep 1 > + > +if ! ps -p $FETCH_PID > /dev/null > +then > + _notrun "precontent watches not supported" That's not so nice and prone to races. Let's do a deterministic test for precontent support, i.e. $here/src/precontent/test-support or $REMOTE_FETCH - $dstdir and abstract this test inside _require_fsnotify_precontent Thanks, Amir.
diff --git a/doc/group-names.txt b/doc/group-names.txt index 6cf71796..93ba6a23 100644 --- a/doc/group-names.txt +++ b/doc/group-names.txt @@ -56,6 +56,7 @@ fiexchange XFS_IOC_EXCHANGE_RANGE ioctl freeze filesystem freeze tests fsck general fsck tests fsmap FS_IOC_GETFSMAP ioctl +fsnotify fsnotify tests fsr XFS free space reorganizer fuzzers filesystem fuzz tests growfs increasing the size of a filesystem diff --git a/src/Makefile b/src/Makefile index 559209be..6dae892e 100644 --- a/src/Makefile +++ b/src/Makefile @@ -40,7 +40,7 @@ EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \ btrfs_crc32c_forged_name.py popdir.pl popattr.py \ soak_duration.awk -SUBDIRS = log-writes perf +SUBDIRS = log-writes perf precontent LLDLIBS = $(LIBHANDLE) $(LIBACL) -lpthread -lrt -luuid diff --git a/src/precontent/Makefile b/src/precontent/Makefile new file mode 100644 index 00000000..367a34bb --- /dev/null +++ b/src/precontent/Makefile @@ -0,0 +1,26 @@ +# SPDX-License-Identifier: GPL-2.0 + +TOPDIR = ../.. +include $(TOPDIR)/include/builddefs + +TARGETS = $(basename $(wildcard *.c)) + +CFILES = $(TARGETS:=.c) +LDIRT = $(TARGETS) + +default: depend $(TARGETS) + +depend: .dep + +include $(BUILDRULES) + +$(TARGETS): $(CFILES) + @echo " [CC] $@" + $(Q)$(LTLINK) $@.c -o $@ $(CFLAGS) $(LDFLAGS) $(LDLIBS) + +install: + $(INSTALL) -m 755 -d $(PKG_LIB_DIR)/src/precontent + $(INSTALL) -m 755 $(TARGETS) $(PKG_LIB_DIR)/src/precontent + +-include .dep + diff --git a/src/precontent/mmap-validate.c b/src/precontent/mmap-validate.c new file mode 100644 index 00000000..af606d5b --- /dev/null +++ b/src/precontent/mmap-validate.c @@ -0,0 +1,227 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _FILE_OFFSET_BITS 64 +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/mman.h> +#include <unistd.h> + +/* 1 MiB. */ +#define FILE_SIZE (1 * 1024 * 1024) +#define PAGE_SIZE 4096 + +#define __free(func) __attribute__((cleanup(func))) + +static void freep(void *ptr) +{ + void *real_ptr = *(void **)ptr; + if (real_ptr == NULL) + return; + free(real_ptr); +} + +static void close_fd(int *fd) +{ + if (*fd < 0) + return; + close(*fd); +} + +static void unmap(void *ptr) +{ + void *real_ptr = *(void **)ptr; + if (real_ptr == NULL) + return; + munmap(real_ptr, PAGE_SIZE); +} + +static void print_buffer(const char *buf, off_t buf_off, off_t off, size_t len) +{ + for (int i = 0; i <= (len / 32); i++) { + printf("%lu:", off + (i * 32)); + + for (int c = 0; c < 32; c++) { + if (!(c % 8)) + printf(" "); + printf("%c", buf[buf_off++]); + } + printf("\n"); + } +} + +static int validate_buffer(const char *type, const char *buf, + const char *pattern, off_t bufoff, off_t off, + size_t len) +{ + + if (memcmp(buf + bufoff, pattern + off, len)) { + printf("Buffers do not match at off %lu size %lu after %s\n", + off, len, type); + printf("read buffer\n"); + print_buffer(buf, bufoff, off, len); + printf("valid buffer\n"); + print_buffer(pattern, off, off, len); + return 1; + } + + return 0; +} + +static int validate_range_fd(int fd, char *pattern, off_t off, size_t len) +{ + char *buf __free(freep) = NULL; + ssize_t ret; + size_t readin = 0; + + buf = malloc(len); + if (!buf) { + perror("malloc buf"); + return 1; + } + + while ((ret = pread(fd, buf + readin, len - readin, off + readin)) > 0) { + readin += ret; + if (readin == len) + break; + } + + if (ret < 0) { + perror("read"); + return 1; + } + + return validate_buffer("read", buf, pattern, 0, off, len); +} + +static int validate_file(const char *file, char *pattern) +{ + int fd __free(close_fd) = -EBADF; + char *buf __free(unmap) = NULL; + int ret; + + fd = open(file, O_RDONLY); + if (fd < 0) { + perror("open file"); + return 1; + } + + /* Cycle through the file and do some random reads and validate them. */ + for (int i = 0; i < 5; i++) { + off_t off = random() % FILE_SIZE; + size_t len = random() % PAGE_SIZE; + + while ((off + len) > FILE_SIZE) { + len = FILE_SIZE - off; + if (len) + break; + len = random() % PAGE_SIZE; + } + + ret = validate_range_fd(fd, pattern, off, len); + if (ret) + return ret; + } + + buf = mmap(NULL, FILE_SIZE, PROT_READ|PROT_EXEC, MAP_PRIVATE, fd, 0); + if (!buf) { + perror("mmap"); + return 1; + } + + /* Validate random ranges of the mmap buffer. */ + for (int i = 0; i < 5; i++) { + off_t off = random() % FILE_SIZE; + size_t len = random() % PAGE_SIZE; + + while ((off + len) > FILE_SIZE) { + len = FILE_SIZE - off; + if (len) + break; + len = random() % PAGE_SIZE; + } + + ret = validate_buffer("mmap", buf, pattern, off, off, len); + if (ret) + return ret; + } + + /* Now check the whole thing, one page at a time. */ + for (int i = 0; i < (FILE_SIZE / PAGE_SIZE); i++) { + ret = validate_buffer("mmap", buf, pattern, i * PAGE_SIZE, + i * PAGE_SIZE, PAGE_SIZE); + if (ret) + return ret; + } + + return 0; +} + +static int create_file(const char *file, char *pattern) +{ + ssize_t ret; + size_t written = 0; + int fd __free(close_fd) = -EBADF; + + fd = open(file, O_RDWR | O_CREAT, 0644); + if (fd < 0) { + perror("opening file"); + return 1; + } + + while ((ret = write(fd, pattern + written, FILE_SIZE - written)) > 0) { + written += ret; + if (written == FILE_SIZE) + break; + } + + if (ret < 0) { + perror("writing to the file"); + return 1; + } + + return 0; +} + +static void generate_pattern(char *pattern) +{ + for (int i = 0; i < (FILE_SIZE / PAGE_SIZE); i++) { + char fill = 'a' + (i % 26); + + memset(pattern + (i * PAGE_SIZE), fill, PAGE_SIZE); + } +} + +static void usage(void) +{ + fprintf(stderr, "Usage: mmap-validate <create|validate> <file>\n"); +} + +int main(int argc, char **argv) +{ + char *pattern __free(freep) = NULL; + + if (argc != 3) { + usage(); + return 1; + } + + pattern = malloc(FILE_SIZE * sizeof(char)); + if (!pattern) { + perror("malloc pattern"); + return 1; + } + + generate_pattern(pattern); + + if (!strcmp(argv[1], "create")) + return create_file(argv[2], pattern); + + if (strcmp(argv[1], "validate")) { + usage(); + return 1; + } + + return validate_file(argv[2], pattern); +} diff --git a/src/precontent/populate.c b/src/precontent/populate.c new file mode 100644 index 00000000..9c935427 --- /dev/null +++ b/src/precontent/populate.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _FILE_OFFSET_BITS 64 +#include <dirent.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <poll.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <unistd.h> + +#define __free(func) __attribute__((cleanup(func))) + +static void close_fd(int *fd) +{ + if (*fd < 0) + return; + close(*fd); +} + +static void close_dir(DIR **dir) +{ + if (*dir == NULL) + return; + closedir(*dir); +} + +static void freep(void *ptr) +{ + void *real_ptr = *(void **)ptr; + if (real_ptr == NULL) + return; + free(real_ptr); +} + +/* + * Dup a path, make sure there's a trailing '/' to make path concat easier. + */ +static char *pathdup(const char *orig) +{ + char *ret; + size_t len = strlen(orig); + + /* Easy path, we have a trailing '/'. */ + if (orig[len - 1] == '/') + return strdup(orig); + + ret = malloc((len + 2) * sizeof(char)); + if (!ret) + return ret; + + memcpy(ret, orig, len); + ret[len] = '/'; + len++; + ret[len] = '\0'; + return ret; +} + +static int process_directory(DIR *srcdir, char *srcpath, char *dstpath) +{ + char *src __free(freep) = NULL; + char *dst __free(freep) = NULL; + size_t srclen = strlen(srcpath) + 256; + size_t dstlen = strlen(dstpath) + 256; + struct dirent *dirent; + + src = malloc(srclen * sizeof(char)); + dst = malloc(dstlen * sizeof(char)); + if (!src || !dst) { + perror("allocating path buf"); + return -1; + } + + errno = 0; + while ((dirent = readdir(srcdir)) != NULL) { + if (!strcmp(dirent->d_name, ".") || + !strcmp(dirent->d_name, "..")) + continue; + + if (dirent->d_type == DT_DIR) { + DIR *nextdir __free(close_dir) = NULL; + struct stat st; + int ret; + + snprintf(src, srclen, "%s%s/", srcpath, dirent->d_name); + snprintf(dst, dstlen, "%s%s/", dstpath, dirent->d_name); + + nextdir = opendir(src); + if (!nextdir) { + fprintf(stderr, "Couldn't open directory %s: %s (%d)\n", + src, strerror(errno), errno); + return -1; + } + + if (stat(src, &st)) { + fprintf(stderr, "Couldn't stat directory %s: %s (%d)\n", + src, strerror(errno), errno); + return -1; + } + + if (mkdir(dst, st.st_mode)) { + fprintf(stderr, "Couldn't mkdir %s: %s (%d)\n", + dst, strerror(errno), errno); + return -1; + } + + ret = process_directory(nextdir, src, dst); + if (ret) + return ret; + } else if (dirent->d_type == DT_REG) { + int fd __free(close_fd) = -EBADF; + struct stat st; + + snprintf(src, srclen, "%s%s", srcpath, dirent->d_name); + snprintf(dst, dstlen, "%s%s", dstpath, dirent->d_name); + + if (stat(src, &st)) { + fprintf(stderr, "Couldn't stat file %s: %s (%d)\n", + src, strerror(errno), errno); + return -1; + } + + fd = open(dst, O_WRONLY|O_CREAT, st.st_mode); + if (fd < 0) { + fprintf(stderr, "Couldn't create file %s: %s (%d)\n", + dst, strerror(errno), errno); + return -1; + } + + if (truncate(dst, st.st_size)) { + fprintf(stderr, "Couldn't truncate file %s: %s (%d)\n", + dst, strerror(errno), errno); + return -1; + } + + + if (fsync(fd)) { + fprintf(stderr, "Couldn't fsync file %s: %s (%d)\n", + dst, strerror(errno), errno); + return -1; + } + + if (posix_fadvise(fd, 0, 0, POSIX_FADV_DONTNEED)) { + fprintf(stderr, "Couldn't clear cache on file %s: %s (%d)\n", + dst, strerror(errno), errno); + return -1; + } + } + errno = 0; + } + + if (errno) { + perror("readdir"); + return -1; + } + return 0; +} + +int main(int argc, char **argv) +{ + DIR *srcdir __free(close_dir) = NULL; + char *dstpath __free(freep) = NULL; + char *srcpath __free(freep) = NULL; + int ret; + + if (argc != 3) { + fprintf(stderr, "Usage: populate <src directory> <dest directory>\n"); + return 1; + } + + srcpath = pathdup(argv[1]); + dstpath = pathdup(argv[2]); + if (!dstpath || !srcpath) { + perror("allocating paths"); + return 1; + } + + srcdir = opendir(srcpath); + if (!srcdir) { + perror("open src directory"); + return 1; + } + + ret = process_directory(srcdir, srcpath, dstpath); + return ret ? 1 : 0; +} diff --git a/src/precontent/remote-fetch.c b/src/precontent/remote-fetch.c new file mode 100644 index 00000000..2e35b9f8 --- /dev/null +++ b/src/precontent/remote-fetch.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _FILE_OFFSET_BITS 64 +#include <dirent.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <poll.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/fanotify.h> +#include <sys/sendfile.h> +#include <sys/stat.h> +#include <unistd.h> + +#ifndef FAN_ERRNO_BITS +#define FAN_ERRNO_BITS 8 +#define FAN_ERRNO_SHIFT (32 - FAN_ERRNO_BITS) +#define FAN_ERRNO_MASK ((1 << FAN_ERRNO_BITS) - 1) +#define FAN_DENY_ERRNO(err) \ + (FAN_DENY | ((((__u32)(err)) & FAN_ERRNO_MASK) << FAN_ERRNO_SHIFT)) +#endif + +#ifndef FAN_PRE_ACCESS +#define FAN_PRE_ACCESS 0x00080000 +#endif + +#ifndef FAN_PRE_MODIFY +#define FAN_PRE_MODIFY 0x00100000 +#endif + +#ifndef FAN_EVENT_INFO_TYPE_RANGE +#define FAN_EVENT_INFO_TYPE_RANGE 6 +struct fanotify_event_info_range { + struct fanotify_event_info_header hdr; + __u32 pad; + __u64 offset; + __u64 count; +}; +#endif + +#define FAN_EVENTS (FAN_PRE_ACCESS | FAN_PRE_MODIFY) + +#define __round_mask(x, y) ((__typeof__(x))((y)-1)) +#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) +#define round_down(x, y) ((x) & ~__round_mask(x, y)) + +static const char *srcpath; +static const char *dstpath; +static int pagesize; +static bool use_sendfile = false; + +#define __free(func) __attribute__((cleanup(func))) + +static void close_dir(DIR **dir) +{ + if (*dir == NULL) + return; + closedir(*dir); +} + +static void close_fd(int *fd) +{ + if (*fd < 0) + return; + close(*fd); +} + +static void freep(void *ptr) +{ + void *real_ptr = *(void **)ptr; + if (real_ptr == NULL) + return; + free(real_ptr); +} + +static int strip_dstpath(char *path) +{ + size_t remaining; + + if (strlen(path) <= strlen(dstpath)) { + fprintf(stderr, "'%s' not in the path '%s'", path, dstpath); + return -1; + } + + if (strncmp(path, dstpath, strlen(dstpath))) { + fprintf(stderr, "path '%s' doesn't start with the source path '%s'\n", + path, dstpath); + return -1; + } + + remaining = strlen(path) - strlen(dstpath); + memmove(path, path + strlen(dstpath), remaining); + + /* strip any leading / in order to make it easier to concat. */ + while (*path == '/') { + if (remaining == 0) { + fprintf(stderr, "you gave us a weird ass string\n"); + return -1; + } + remaining--; + memmove(path, path + 1, remaining); + } + path[remaining] = '\0'; + return 0; +} + +/* + * Dup a path, make sure there's a trailing '/' to make path concat easier. + */ +static char *pathdup(const char *orig) +{ + char *ret; + size_t len = strlen(orig); + + /* Easy path, we have a trailing '/'. */ + if (orig[len - 1] == '/') + return strdup(orig); + + ret = malloc((len + 2) * sizeof(char)); + if (!ret) + return ret; + + memcpy(ret, orig, len); + ret[len] = '/'; + len++; + ret[len] = '\0'; + return ret; +} + +static char *get_relpath(int fd) +{ + char procfd_path[PATH_MAX]; + char abspath[PATH_MAX]; + ssize_t path_len; + int ret; + + /* readlink doesn't NULL terminate. */ + memset(abspath, 0, sizeof(abspath)); + + snprintf(procfd_path, sizeof(procfd_path), "/proc/self/fd/%d", fd); + path_len = readlink(procfd_path, abspath, sizeof(abspath) - 1); + if (path_len < 0) { + perror("readlink"); + return NULL; + } + + ret = strip_dstpath(abspath); + if (ret < 0) + return NULL; + + return strdup(abspath); +} + +static int copy_range(int src_fd, int fd, off_t offset, size_t count) +{ + off_t src_offset = offset; + ssize_t copied; + + if (use_sendfile) + goto slow; + + while ((copied = copy_file_range(src_fd, &src_offset, fd, &offset, + count, 0)) >= 0) { + if (copied == 0) + return 0; + + count -= copied; + if (count == 0) + return 0; + } + + if (errno != EXDEV) { + perror("copy_file_range"); + return -1; + } + use_sendfile = true; + +slow: + /* I love linux interfaces. */ + if (lseek(fd, offset, SEEK_SET) == (off_t)-1) { + perror("seeking"); + return -1; + } + + while ((copied = sendfile(fd, src_fd, &src_offset, count)) >= 0) { + if (copied == 0) + return 0; + + count -= copied; + if (count == 0) + return 0; + } + + perror("sendfile"); + return -1; +} + +static int handle_event(int fanotify_fd, int fd, off_t offset, size_t count) +{ + char path[PATH_MAX]; + char *relpath __free(freep) = NULL; + int src_fd __free(close_fd) = -1; + off_t end = offset + count; + blkcnt_t src_blocks; + struct stat st; + + relpath = get_relpath(fd); + if (!relpath) + return -1; + + offset = round_down(offset, pagesize); + end = round_up(end, pagesize); + count = end - offset; + + snprintf(path, sizeof(path), "%s%s", srcpath, relpath); + src_fd = open(path, O_RDONLY); + if (src_fd < 0) { + fprintf(stderr, "srcpath %s relpath %s\n", srcpath, relpath); + fprintf(stderr, "error opening file %s: %s (%d)\n", path, strerror(errno), errno); + return -1; + } + + if (fstat(src_fd, &st)) { + perror("src fd is fucked"); + return -1; + } + + src_blocks = st.st_blocks; + + if (fstat(fd, &st)) { + perror("fd is fucked"); + return -1; + } + + /* + * If we are the same size or larger (which can happen if we copy zero's + * instead of inserting a hole) then just assume we're full. This is + * approximation can fall over, but its good enough for a PoC. + */ + if (st.st_blocks >= src_blocks) { + int ret; + + snprintf(path, sizeof(path), "%s%s", dstpath, relpath); + ret = fanotify_mark(fanotify_fd, FAN_MARK_REMOVE, + FAN_EVENTS, -1, path); + if (ret < 0) { + /* We already removed the mark, carry on. */ + if (errno == ENOENT) { + errno = 0; + return 0; + } + perror("removing fanotify mark"); + return -1; + } + return 0; + } + + + return copy_range(src_fd, fd, offset, count); +} + +static int handle_events(int fd) +{ + const struct fanotify_event_metadata *metadata; + struct fanotify_event_metadata buf[200]; + ssize_t len; + struct fanotify_response response; + int ret = 0; + + len = read(fd, (void *)buf, sizeof(buf)); + if (len <= 0 && errno != EINTR) { + perror("reading fanotify events"); + return -1; + } + + metadata = buf; + while(FAN_EVENT_OK(metadata, len)) { + off_t offset = 0; + size_t count = 0; + + if (metadata->vers != FANOTIFY_METADATA_VERSION) { + fprintf(stderr, "invalid metadata version, have %d, expect %d\n", + metadata->vers, FANOTIFY_METADATA_VERSION); + return -1; + } + if (metadata->fd < 0) { + fprintf(stderr, "metadata fd is an error\n"); + return -1; + } + if (!(metadata->mask & FAN_EVENTS)) { + fprintf(stderr, "metadata mask incorrect %llu\n", + metadata->mask); + return -1; + } + + /* + * We have a specific range, load that instead of filling the + * entire file in. + */ + if (metadata->event_len > FAN_EVENT_METADATA_LEN) { + const struct fanotify_event_info_range *range; + range = (const struct fanotify_event_info_range *)(metadata + 1); + if (range->hdr.info_type == FAN_EVENT_INFO_TYPE_RANGE) { + count = range->count; + offset = range->offset; + if (count == 0) { + ret = 0; + goto next; + } + } + } + + /* We don't have a range, pre-fill the whole file. */ + if (count == 0) { + struct stat st; + + if (fstat(metadata->fd, &st)) { + perror("stat() on opened file"); + return -1; + } + + count = st.st_size; + } + + ret = handle_event(fd, metadata->fd, offset, count); +next: + response.fd = metadata->fd; + if (ret) + response.response = FAN_DENY_ERRNO(errno); + else + response.response = FAN_ALLOW; + write(fd, &response, sizeof(response)); + close(metadata->fd); + metadata = FAN_EVENT_NEXT(metadata, len); + } + + return ret; +} + +static int add_marks(const char *src, int fanotify_fd) +{ + char *path __free(freep) = NULL; + DIR *dir __free(close_dir) = NULL; + size_t pathlen = strlen(src) + 256; + struct dirent *dirent; + + path = malloc(pathlen * sizeof(char)); + if (!path) { + perror("allocating path buf"); + return -1; + } + + dir = opendir(src); + if (!dir) { + fprintf(stderr, "Couldn't open directory %s: %s (%d)\n", + src, strerror(errno), errno); + return -1; + } + + errno = 0; + while ((dirent = readdir(dir)) != NULL) { + int ret; + + if (!strcmp(dirent->d_name, ".") || + !strcmp(dirent->d_name, "..")) + continue; + + if (dirent->d_type == DT_DIR) { + snprintf(path, pathlen, "%s%s/", src, dirent->d_name); + ret = add_marks(path, fanotify_fd); + if (ret) + return ret; + } else if (dirent->d_type == DT_REG) { + ret = fanotify_mark(fanotify_fd, FAN_MARK_ADD, + FAN_EVENTS, dirfd(dir), + dirent->d_name); + if (ret < 0) { + perror("fanotify_mark"); + return -1; + } + } + errno = 0; + } + return 0; +} + +static void usage(void) +{ + fprintf(stderr, "Usage: remote-fetch <src directory> <dest directory>\n"); +} + +int main(int argc, char **argv) +{ + int fd __free(close_fd) = -1; + int dirfd __free(close_fd) = -1; + int ret; + + if (argc != 3) { + usage(); + return 1; + } + + pagesize = sysconf(_SC_PAGESIZE); + if (pagesize < 0) { + perror("sysconf"); + return 1; + } + + srcpath = pathdup(argv[1]); + dstpath = pathdup(argv[2]); + if (!srcpath || !dstpath) { + perror("allocate paths"); + return 1; + } + + dirfd = open(dstpath, O_DIRECTORY | O_RDONLY); + if (dirfd < 0) { + perror("open dstpath"); + return 1; + } + + fd = fanotify_init(FAN_CLASS_PRE_CONTENT | FAN_UNLIMITED_MARKS, O_WRONLY | O_LARGEFILE); + if (fd < 0) { + perror("fanotify_init"); + return 1; + } + + ret = add_marks(dstpath, fd); + if (ret < 0) + return 1; + + for (;;) { + ret = handle_events(fd); + if (ret) + break; + } + + return (ret < 0) ? 1 : 0; +} diff --git a/tests/generic/800 b/tests/generic/800 new file mode 100644 index 00000000..08ac5b26 --- /dev/null +++ b/tests/generic/800 @@ -0,0 +1,68 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2024 Meta Platforms, Inc. All Rights Reserved. +# +# FS QA Test 800 +# +# Validate the pre-content related fanotify features +# +# The mmap-verify pre-content tool generates a file and then validates that the +# pre-content watched directory properly fills it in with a mixture of page +# faults and normal reads. +# +. ./common/preamble +_begin_fstest quick auto fsnotify + +_cleanup() +{ + cd / + rm -rf $TEST_DIR/dst-$seq + rm -rf $TEST_DIR/src-$seq +} + +# real QA test starts here +_supported_fs generic +_require_test +_require_test_program "precontent/mmap-validate" +_require_test_program "precontent/populate" +_require_test_program "precontent/remote-fetch" + +dstdir=$TEST_DIR/dst-$seq +srcdir=$TEST_DIR/src-$seq + +POPULATE=$here/src/precontent/populate +REMOTE_FETCH=$here/src/precontent/remote-fetch +MMAP_VALIDATE=$here/src/precontent/mmap-validate + +mkdir $dstdir $srcdir + +# Generate the test file +$MMAP_VALIDATE create $srcdir/validate + +# Generate the stub file in the watch directory +$POPULATE $srcdir $dstdir + +# Start the remote watcher +$REMOTE_FETCH $srcdir $dstdir & + +FETCH_PID=$! + +# We may not support fanotify, give it a second to start and then make sure the +# fetcher is running before we try to validate the buffer +sleep 1 + +if ! ps -p $FETCH_PID > /dev/null +then + _notrun "precontent watches not supported" +fi + +$MMAP_VALIDATE validate $dstdir/validate + +kill -9 $FETCH_PID &> /dev/null +wait $FETCH_PID &> /dev/null + +echo "Silence is golden" + +# success, all done +status=$? +exit diff --git a/tests/generic/800.out b/tests/generic/800.out new file mode 100644 index 00000000..bdfaa2ce --- /dev/null +++ b/tests/generic/800.out @@ -0,0 +1,2 @@ +QA output created by 800 +Silence is golden
This is a test to validate the precontent hooks work properly for reads and page faults. Signed-off-by: Josef Bacik <josef@toxicpanda.com> --- doc/group-names.txt | 1 + src/Makefile | 2 +- src/precontent/Makefile | 26 ++ src/precontent/mmap-validate.c | 227 +++++++++++++++++ src/precontent/populate.c | 188 ++++++++++++++ src/precontent/remote-fetch.c | 441 +++++++++++++++++++++++++++++++++ tests/generic/800 | 68 +++++ tests/generic/800.out | 2 + 8 files changed, 954 insertions(+), 1 deletion(-) create mode 100644 src/precontent/Makefile create mode 100644 src/precontent/mmap-validate.c create mode 100644 src/precontent/populate.c create mode 100644 src/precontent/remote-fetch.c create mode 100644 tests/generic/800 create mode 100644 tests/generic/800.out