Dominique Martinet <[email protected]> wrote: > Eric Wong wrote on Mon, Jan 31, 2022 at 02:03:11AM +0000: > > Ah, intentionally setting BTRFS_TESTDIR to something that isn't > > btrfs will break, yes. > > Ok, so this is specific to the test. > Checking now nodatacow_fh skips files with non-btrfs magic, so it looks > good to me! > > I've taken a look at the code now, just one more question: I don't > understand why you've made the ioctl value depend on endianness ?
Actually, it's not endianess, it's architecture specific :x The nasty patch below fixes it. I really wish there are better options for scripting languages to use C headers :< > That aside the code looks good to me, if you do Reviewed-by tags feel > free to add mine (Dominique Martinet <[email protected]>) once that > question is answered. > If you don't care, I don't care either :) Thanks, just added the Noticed-by: as an attribution to the below patch. > this isn't really a problem, I've only tried because I'm a monkey :) Yeah. Setting BTRFS_TESTDIR to a non-btrfs dir isn't going to be supported :> > Thanks again for the support, don't hesitate to ask if you need further > info or tests for the zfs problems. You're welcome, and will do. -----8<----- Subject: [PATCH] syscall: FS_IOC_*FLAGS: define on per-architecture basis It turns out these Linux ioctls are unfortunately architecture-dependent, and not endian-dependent. Fixup some warning messages while we're at it, too. Fixes: 14fa0abdcc7b6513 ("rewrite Linux nodatacow use in pure Perl w/o system") Link: https://public-inbox.org/meta/[email protected]/ Noticed-by: Dominique Martinet <[email protected]> --- lib/PublicInbox/Syscall.pm | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/lib/PublicInbox/Syscall.pm b/lib/PublicInbox/Syscall.pm index bcfae2cb..31c67a14 100644 --- a/lib/PublicInbox/Syscall.pm +++ b/lib/PublicInbox/Syscall.pm @@ -69,6 +69,7 @@ our ( ); my $SYS_fstatfs; # don't need fstatfs64, just statfs.f_type +my ($FS_IOC_GETFLAGS, $FS_IOC_SETFLAGS); my $SFD_CLOEXEC = 02000000; # Perl does not expose O_CLOEXEC our $no_deprecated = 0; @@ -98,6 +99,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 327; $SYS_renameat2 //= 353; $SYS_fstatfs = 100; + $FS_IOC_GETFLAGS = 0x80046601; + $FS_IOC_SETFLAGS = 0x40046602; } elsif ($machine eq "x86_64") { $SYS_epoll_create = 213; $SYS_epoll_ctl = 233; @@ -105,6 +108,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 289; $SYS_renameat2 //= 316; $SYS_fstatfs = 138; + $FS_IOC_GETFLAGS = 0x80086601; + $FS_IOC_SETFLAGS = 0x40086602; } elsif ($machine eq 'x32') { $SYS_epoll_create = 1073742037; $SYS_epoll_ctl = 1073742057; @@ -112,6 +117,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 1073742113; $SYS_renameat2 //= 0x40000000 + 316; $SYS_fstatfs = 138; + $FS_IOC_GETFLAGS = 0x80046601; + $FS_IOC_SETFLAGS = 0x40046602; } elsif ($machine eq 'sparc64') { $SYS_epoll_create = 193; $SYS_epoll_ctl = 194; @@ -121,6 +128,8 @@ if ($^O eq "linux") { $SYS_renameat2 //= 345; $SFD_CLOEXEC = 020000000; $SYS_fstatfs = 158; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; } elsif ($machine =~ m/^parisc/) { $SYS_epoll_create = 224; $SYS_epoll_ctl = 225; @@ -135,6 +144,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 313; $SYS_renameat2 //= 357; $SYS_fstatfs = 100; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; } elsif ($machine eq "ppc") { $SYS_epoll_create = 236; $SYS_epoll_ctl = 237; @@ -143,6 +154,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 313; $SYS_renameat2 //= 357; $SYS_fstatfs = 100; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; } elsif ($machine =~ m/^s390/) { $SYS_epoll_create = 249; $SYS_epoll_ctl = 250; @@ -174,6 +187,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 74; $SYS_renameat2 //= 276; $SYS_fstatfs = 44; + $FS_IOC_GETFLAGS = 0x80086601; + $FS_IOC_SETFLAGS = 0x40086602; } elsif ($machine =~ m/arm(v\d+)?.*l/) { # ARM OABI $SYS_epoll_create = 250; @@ -191,6 +206,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 5283; $SYS_renameat2 //= 5311; $SYS_fstatfs = 5135; + $FS_IOC_GETFLAGS = 0x40046601; + $FS_IOC_SETFLAGS = 0x80046602; } elsif ($machine =~ m/^mips/) { $SYS_epoll_create = 4248; $SYS_epoll_ctl = 4249; @@ -199,6 +216,8 @@ if ($^O eq "linux") { $SYS_signalfd4 = 4324; $SYS_renameat2 //= 4351; $SYS_fstatfs = 4100; + $FS_IOC_GETFLAGS = 0x40046601; + $FS_IOC_SETFLAGS = 0x80046602; } else { # as a last resort, try using the *.ph files which may not # exist or may be wrong @@ -345,22 +364,14 @@ sub nodatacow_fh { my $f_type = unpack('l!', $buf); # statfs.f_type is a signed word return if $f_type != 0x9123683E; # BTRFS_SUPER_MAGIC - state ($FS_IOC_GETFLAGS, $FS_IOC_SETFLAGS); - unless (defined $FS_IOC_GETFLAGS) { - if (substr($Config{byteorder}, 0, 4) eq '1234') { - $FS_IOC_GETFLAGS = 0x80086601; - $FS_IOC_SETFLAGS = 0x40086602; - } else { # Big endian - $FS_IOC_GETFLAGS = 0x40086601; - $FS_IOC_SETFLAGS = 0x80086602; - } - } + $FS_IOC_GETFLAGS // + return warn('FS_IOC_GETFLAGS undefined for platform'); ioctl($fh, $FS_IOC_GETFLAGS, $buf) // - return warn("FS_IOC_GET_FLAGS: $!\n"); + return warn("FS_IOC_GETFLAGS: $!\n"); my $attr = unpack('l!', $buf); return if ($attr & 0x00800000); # FS_NOCOW_FL; ioctl($fh, $FS_IOC_SETFLAGS, pack('l', $attr | 0x00800000)) // - warn("FS_IOC_SET_FLAGS: $!\n"); + warn("FS_IOC_SETFLAGS: $!\n"); } sub nodatacow_dir { -- unsubscribe: one-click, see List-Unsubscribe header archive: https://public-inbox.org/meta/
