diff options
| -rw-r--r-- | ChangeLog | 4 | ||||
| -rw-r--r-- | src/bindfs.1 | 8 | ||||
| -rw-r--r-- | src/bindfs.c | 65 | ||||
| -rwxr-xr-x | tests/test_bindfs.rb | 19 |
4 files changed, 80 insertions, 16 deletions
@@ -1,3 +1,7 @@ +2019-04-29 Martin Pärtel <martin dot partel at gmail dot com> + + * Added --forward-odirect. Bindfs now clears O_DIRECT by default (PR #74, thanks barp@!). + 2019-03-31 Martin Pärtel <martin dot partel at gmail dot com> * Fixes to --gid-offset when used with a setgid bit or with --create-as-mounter (PR #73, thanks ehmm@!). diff --git a/src/bindfs.1 b/src/bindfs.1 index d47720f..6f24267 100644 --- a/src/bindfs.1 +++ b/src/bindfs.1 @@ -366,6 +366,14 @@ Run bindfs in multithreaded mode. While bindfs is designed to be otherwise thread-safe, there is currently a race condition that may pose a security risk for some use cases. See \fB\%BUGS\fP below. +.TP +.B \-\-forward\-odirect=\fIalignment\fP, \-o forward\-odirect=\fIalignment\fP +Enable experimental \fBO_DIRECT\fP forwarding, with all read/write requests rounded +to the given alignment (in bytes). By default, the \fBO_DIRECT\fP flag is +not forwarded to the underlying FS. +See \fBopen\fP(2) for details about \fBO_DIRECT\fP. + +Only works on Linux. Ignored on other platforms. .SH FUSE OPTIONS .TP diff --git a/src/bindfs.c b/src/bindfs.c index 6f16d28..dc8e25c 100644 --- a/src/bindfs.c +++ b/src/bindfs.c @@ -194,13 +194,14 @@ static struct Settings { int enable_ioctl; - uid_t uid_offset; - gid_t gid_offset; - #ifdef __linux__ - size_t linux_page_size; + int forward_odirect; + size_t odirect_alignment; #endif + uid_t uid_offset; + gid_t gid_offset; + } settings; @@ -605,12 +606,12 @@ static size_t round_up_buffer_size_for_direct_io(size_t size) // `man 2 open` says this should be block-size aligned and that there's no // general way to determine this. Empirically the page size should be good enough. // See also: Pull Request #74 - size_t page_size = settings.linux_page_size; - size_t rem = size % page_size; + size_t alignment = settings.odirect_alignment; + size_t rem = size % alignment; if (rem == 0) { return size; } - return size - rem + page_size; + return size - rem + alignment; } #endif @@ -1084,7 +1085,14 @@ static int bindfs_create(const char *path, mode_t mode, struct fuse_file_info *f mode |= S_IFREG; /* tell permchain_apply this is a regular file */ mode = permchain_apply(settings.create_permchain, mode); - fd = open(real_path, fi->flags, mode & 0777); + int flags = fi->flags; +#ifdef __linux__ + if (!settings.forward_odirect) { + flags &= ~O_DIRECT; + } +#endif + + fd = open(real_path, flags, mode & 0777); if (fd == -1) { free(real_path); return -errno; @@ -1107,7 +1115,14 @@ static int bindfs_open(const char *path, struct fuse_file_info *fi) if (real_path == NULL) return -errno; - fd = open(real_path, fi->flags); + int flags = fi->flags; +#ifdef __linux__ + if (!settings.forward_odirect) { + flags &= ~O_DIRECT; + } +#endif + + fd = open(real_path, flags); free(real_path); if (fd == -1) return -errno; @@ -1130,7 +1145,7 @@ static int bindfs_read(const char *path, char *buf, size_t size, off_t offset, #ifdef __linux__ size_t mmap_size = 0; - if (fi->flags & O_DIRECT) { + if ((fi->flags & O_DIRECT) && settings.forward_odirect) { mmap_size = round_up_buffer_size_for_direct_io(size); target_buf = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); if (target_buf == MAP_FAILED) { @@ -1166,7 +1181,7 @@ static int bindfs_write(const char *path, const char *buf, size_t size, #ifdef __linux__ size_t mmap_size = 0; - if (fi->flags & O_DIRECT) { + if ((fi->flags & O_DIRECT) && settings.forward_odirect) { mmap_size = round_up_buffer_size_for_direct_io(size); source_buf = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); if (source_buf == MAP_FAILED) { @@ -1556,6 +1571,7 @@ static void print_usage(const char *progname) " --block-devices-as-files Show block devices as regular files.\n" " --multithreaded Enable multithreaded mode. See man page\n" " for security issue with current implementation.\n" + " --forward-odirect=... Forward O_DIRECT (it's cleared by default).\n" "\n" "FUSE options:\n" " -o opt[,opt,...] Mount options.\n" @@ -1980,6 +1996,7 @@ int main(int argc, char *argv[]) char *resolved_symlink_deletion; int no_allow_other; int multithreaded; + char *forward_odirect; char *uid_offset; char *gid_offset; } od; @@ -2051,6 +2068,7 @@ int main(int argc, char *argv[]) OPT2("--disable-lock-forwarding", "disable-lock-forwarding", OPTKEY_DISABLE_LOCK_FORWARDING), OPT2("--enable-ioctl", "enable-ioctl", OPTKEY_ENABLE_IOCTL), OPT_OFFSET2("--multithreaded", "multithreaded", multithreaded, -1), + OPT_OFFSET2("--forward-odirect=%s", "forward-odirect=%s", forward_odirect, -1), OPT_OFFSET2("--uid-offset=%s", "uid-offset=%s", uid_offset, 0), OPT_OFFSET2("--gid-offset=%s", "gid-offset=%s", gid_offset, 0), @@ -2102,7 +2120,8 @@ int main(int argc, char *argv[]) settings.uid_offset = 0; settings.gid_offset = 0; #ifdef __linux__ - settings.linux_page_size = sysconf(_SC_PAGESIZE); + settings.forward_odirect = 0; + settings.odirect_alignment = 0; #endif atexit(&atexit_func); @@ -2193,7 +2212,7 @@ int main(int argc, char *argv[]) char* endptr = od.uid_offset; settings.uid_offset = strtoul(od.uid_offset, &endptr, 10); if (*endptr != '\0') { - fprintf(stderr, "Error: Value of --uid-offset must be a positive integer.\n"); + fprintf(stderr, "Error: Value of --uid-offset must be an integer.\n"); return 1; } } @@ -2210,9 +2229,27 @@ int main(int argc, char *argv[]) char* endptr = od.gid_offset; settings.gid_offset = strtoul(od.gid_offset, &endptr, 10); if (*endptr != '\0') { - fprintf(stderr, "Error: Value of --gid-offset must be a positive integer.\n"); + fprintf(stderr, "Error: Value of --gid-offset must be an integer.\n"); + return 1; + } + } + + if (od.forward_odirect) { +#ifdef __linux__ + settings.forward_odirect = 1; + char* endptr = od.forward_odirect; + settings.odirect_alignment = strtoul(od.forward_odirect, &endptr, 10); + if (*endptr != '\0') { + fprintf(stderr, "Error: Value of --forward-odirect must be an integer.\n"); + return 1; + } + if (settings.odirect_alignment == 0) { + fprintf(stderr, "Error: Value of --forward-odirect must be positive.\n"); return 1; } +#else + fprintf(stderr, "Warning: --forward-odirect is not supported on this platform.\n"); +#endif } /* Parse user and group for new creates */ diff --git a/tests/test_bindfs.rb b/tests/test_bindfs.rb index a6ecf2c..bfc6d64 100755 --- a/tests/test_bindfs.rb +++ b/tests/test_bindfs.rb @@ -782,14 +782,29 @@ if `uname`.strip == 'Linux' ('abc' * 10000)[0...8192] end - testenv("", :title => "O_DIRECT reads") do + testenv("", :title => "O_DIRECT reads with O_DIRECT ignored") do File.write("src/f", odirect_data) read_data = `#{$tests_dir}/odirect_read mnt/f` assert { $?.success? } assert { read_data == odirect_data } end - testenv("", :title => "O_DIRECT writes") do + testenv("", :title => "O_DIRECT writes with O_DIRECT ignored") do + IO.popen("#{$tests_dir}/odirect_write mnt/f", "w") do |pipe| + pipe.write(odirect_data) + end + assert { $?.success? } + assert { File.read("src/f") == odirect_data } + end + + testenv("--forward-odirect=512", :title => "O_DIRECT reads with O_DIRECT forwarded") do + File.write("src/f", odirect_data) + read_data = `#{$tests_dir}/odirect_read mnt/f` + assert { $?.success? } + assert { read_data == odirect_data } + end + + testenv("--forward-odirect=512", :title => "O_DIRECT writes with O_DIRECT forwarded") do IO.popen("#{$tests_dir}/odirect_write mnt/f", "w") do |pipe| pipe.write(odirect_data) end |