| Message ID | 20171117202524.24696-2-ross.zwisler@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 17, 2017 at 12:25 PM, Ross Zwisler <ross.zwisler@linux.intel.com> wrote: > Add support for a new -S flag to xfs_io's mmap command. This opens the > mapping with the (MAP_SYNC | MAP_SHARED_VALIDATE) flags instead of the > standard MAP_SHARED flag. > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > Suggested-by: Dave Chinner <david@fromorbit.com> > --- > configure.ac | 1 + > include/builddefs.in | 1 + > include/linux.h | 5 +++++ > io/io.h | 1 + > io/mmap.c | 19 ++++++++++++++----- > m4/package_libcdev.m4 | 16 ++++++++++++++++ > man/man8/xfs_io.8 | 6 +++++- > 7 files changed, 43 insertions(+), 6 deletions(-) > > diff --git a/configure.ac b/configure.ac > index cb23fb8..7153c9f 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -162,6 +162,7 @@ AC_HAVE_FSETXATTR > AC_HAVE_MREMAP > AC_NEED_INTERNAL_FSXATTR > AC_HAVE_GETFSMAP > +AC_HAVE_MAP_SYNC > > if test "$enable_blkid" = yes; then > AC_HAVE_BLKID_TOPO > diff --git a/include/builddefs.in b/include/builddefs.in > index 1d454b6..78b71fe 100644 > --- a/include/builddefs.in > +++ b/include/builddefs.in > @@ -114,6 +114,7 @@ HAVE_FSETXATTR = @have_fsetxattr@ > HAVE_MREMAP = @have_mremap@ > NEED_INTERNAL_FSXATTR = @need_internal_fsxattr@ > HAVE_GETFSMAP = @have_getfsmap@ > +HAVE_MAP_SYNC = @have_map_sync@ > > GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall > # -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-decl > diff --git a/include/linux.h b/include/linux.h > index 6ce344c..4ee03ed 100644 > --- a/include/linux.h > +++ b/include/linux.h > @@ -327,4 +327,9 @@ fsmap_advance( > #define HAVE_GETFSMAP > #endif /* HAVE_GETFSMAP */ > > +#ifndef HAVE_MAP_SYNC > +#define MAP_SYNC 0x80000 Hmm, this is the x86 specific value of MAP_SYNC. I think it would be better to define MAP_SYNC to zero in this case and check for MAP_SYNC == 0 at run time.
On Fri, Nov 17, 2017 at 01:25:23PM -0700, Ross Zwisler wrote: > Add support for a new -S flag to xfs_io's mmap command. This opens the > mapping with the (MAP_SYNC | MAP_SHARED_VALIDATE) flags instead of the > standard MAP_SHARED flag. > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > Suggested-by: Dave Chinner <david@fromorbit.com> > --- > configure.ac | 1 + > include/builddefs.in | 1 + > include/linux.h | 5 +++++ > io/io.h | 1 + > io/mmap.c | 19 ++++++++++++++----- > m4/package_libcdev.m4 | 16 ++++++++++++++++ > man/man8/xfs_io.8 | 6 +++++- > 7 files changed, 43 insertions(+), 6 deletions(-) > > diff --git a/configure.ac b/configure.ac > index cb23fb8..7153c9f 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -162,6 +162,7 @@ AC_HAVE_FSETXATTR > AC_HAVE_MREMAP > AC_NEED_INTERNAL_FSXATTR > AC_HAVE_GETFSMAP > +AC_HAVE_MAP_SYNC > > if test "$enable_blkid" = yes; then > AC_HAVE_BLKID_TOPO > diff --git a/include/builddefs.in b/include/builddefs.in > index 1d454b6..78b71fe 100644 > --- a/include/builddefs.in > +++ b/include/builddefs.in > @@ -114,6 +114,7 @@ HAVE_FSETXATTR = @have_fsetxattr@ > HAVE_MREMAP = @have_mremap@ > NEED_INTERNAL_FSXATTR = @need_internal_fsxattr@ > HAVE_GETFSMAP = @have_getfsmap@ > +HAVE_MAP_SYNC = @have_map_sync@ > > GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall > # -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-decl > diff --git a/include/linux.h b/include/linux.h > index 6ce344c..4ee03ed 100644 > --- a/include/linux.h > +++ b/include/linux.h > @@ -327,4 +327,9 @@ fsmap_advance( > #define HAVE_GETFSMAP > #endif /* HAVE_GETFSMAP */ > > +#ifndef HAVE_MAP_SYNC > +#define MAP_SYNC 0x80000 > +#define MAP_SHARED_VALIDATE 0x3 > +#endif /* HAVE_MAP_SYNC */ Hmm, what's the point of ifndef/define if you have an configure.ac check? > + > #endif /* __XFS_LINUX_H__ */ > diff --git a/io/io.h b/io/io.h > index 3862985..8b2753b 100644 > --- a/io/io.h > +++ b/io/io.h > @@ -65,6 +65,7 @@ typedef struct mmap_region { > size_t length; /* length of mapping */ > off64_t offset; /* start offset into backing file */ > int prot; /* protection mode of the mapping */ > + bool map_sync; /* is this a MAP_SYNC mapping? */ > char *name; /* name of backing file */ > } mmap_region_t; > > diff --git a/io/mmap.c b/io/mmap.c > index 7a8150e..520b037 100644 > --- a/io/mmap.c > +++ b/io/mmap.c > @@ -42,7 +42,7 @@ print_mapping( > int index, > int braces) > { > - unsigned char buffer[8] = { 0 }; > + char buffer[8] = { 0 }; > int i; > > static struct { > @@ -57,6 +57,10 @@ print_mapping( > > for (i = 0, p = pflags; p->prot != PROT_NONE; i++, p++) > buffer[i] = (map->prot & p->prot) ? p->mode : '-'; > + > + if (map->map_sync) > + sprintf(&buffer[i], " S"); Does buffer need enlarging here? > + > printf("%c%03d%c 0x%lx - 0x%lx %s %14s (%lld : %ld)\n", > braces? '[' : ' ', index, braces? ']' : ' ', > (unsigned long)map->addr, > @@ -146,6 +150,7 @@ mmap_help(void) > " -r -- map with PROT_READ protection\n" > " -w -- map with PROT_WRITE protection\n" > " -x -- map with PROT_EXEC protection\n" > +" -S -- map with MAP_SHARED_VALIDATE and MAP_SYNC flags\n" > " -s <size> -- first do mmap(size)/munmap(size), try to reserve some free space\n" > " If no protection mode is specified, all are used by default.\n" > "\n")); > @@ -161,7 +166,7 @@ mmap_f( > void *address = NULL; > char *filename; > size_t blocksize, sectsize; > - int c, prot = 0; > + int c, prot = 0, flags = MAP_SHARED; > > if (argc == 1) { > if (mapping) > @@ -184,7 +189,7 @@ mmap_f( > > init_cvtnum(&blocksize, §size); > > - while ((c = getopt(argc, argv, "rwxs:")) != EOF) { > + while ((c = getopt(argc, argv, "rwxSs:")) != EOF) { > switch (c) { > case 'r': > prot |= PROT_READ; > @@ -195,6 +200,9 @@ mmap_f( > case 'x': > prot |= PROT_EXEC; > break; > + case 'S': > + flags = MAP_SHARED_VALIDATE | MAP_SYNC; > + break; > case 's': > length2 = cvtnum(blocksize, sectsize, optarg); > break; > @@ -238,7 +246,7 @@ mmap_f( > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > munmap(address, length2); > } > - address = mmap(address, length, prot, MAP_SHARED, file->fd, offset); > + address = mmap(address, length, prot, flags, file->fd, offset); > if (address == MAP_FAILED) { > perror("mmap"); > free(filename); > @@ -263,6 +271,7 @@ mmap_f( > mapping->offset = offset; > mapping->name = filename; > mapping->prot = prot; > + mapping->map_sync = (flags == (MAP_SHARED_VALIDATE | MAP_SYNC)); > return 0; > } > > @@ -676,7 +685,7 @@ mmap_init(void) > mmap_cmd.argmax = -1; > mmap_cmd.flags = CMD_NOMAP_OK | CMD_NOFILE_OK | > CMD_FOREIGN_OK | CMD_FLAG_ONESHOT; > - mmap_cmd.args = _("[N] | [-rwx] [-s size] [off len]"); > + mmap_cmd.args = _("[N] | [-rwxS] [-s size] [off len]"); > mmap_cmd.oneline = > _("mmap a range in the current file, show mappings"); > mmap_cmd.help = mmap_help; > diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4 > index fdf9d69..598f5df 100644 > --- a/m4/package_libcdev.m4 > +++ b/m4/package_libcdev.m4 > @@ -314,3 +314,19 @@ AC_DEFUN([AC_HAVE_GETFSMAP], > AC_MSG_RESULT(no)) > AC_SUBST(have_getfsmap) > ]) > + > +# > +# Check if we have MAP_SYNC defines (Linux) > +# > +AC_DEFUN([AC_HAVE_MAP_SYNC], > + [ AC_MSG_CHECKING([for MAP_SYNC]) > + AC_TRY_COMPILE([ > +#include <asm-generic/mman.h> > +#include <asm-generic/mman-common.h> > + ], [ > + int flags = MAP_SHARED_VALIDATE | MAP_SYNC; > + ], have_map_sync=yes > + AC_MSG_RESULT(yes), > + AC_MSG_RESULT(no)) > + AC_SUBST(have_map_sync) > + ]) > diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 > index 9bf1a47..1693f7f 100644 > --- a/man/man8/xfs_io.8 > +++ b/man/man8/xfs_io.8 > @@ -764,7 +764,7 @@ Each (sec, nsec) pair constitutes a single timestamp value. > > .SH MEMORY MAPPED I/O COMMANDS > .TP > -.BI "mmap [ " N " | [[ \-rwx ] [\-s " size " ] " "offset length " ]] > +.BI "mmap [ " N " | [[ \-rwxS ] [\-s " size " ] " "offset length " ]] > With no arguments, > .B mmap > shows the current mappings. Specifying a single numeric argument > @@ -780,6 +780,10 @@ PROT_WRITE > .RB ( \-w ), > and PROT_EXEC > .RB ( \-x ). > +The mapping will be created with the MAP_SHARED flag by default, or with the > +Linux specific (MAP_SYNC | MAP_SHARED_VALIDATE) flags if > +.B -S > +is given. Woo, documentation! --D > .BI \-s " size" > is used to do a mmap(size) && munmap(size) operation at first, try to reserve some > extendible free memory space, if > -- > 2.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Nov 17, 2017 at 12:35:43PM -0800, Dan Williams wrote: > On Fri, Nov 17, 2017 at 12:25 PM, Ross Zwisler > <ross.zwisler@linux.intel.com> wrote: > > Add support for a new -S flag to xfs_io's mmap command. This opens the > > mapping with the (MAP_SYNC | MAP_SHARED_VALIDATE) flags instead of the > > standard MAP_SHARED flag. > > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > > Suggested-by: Dave Chinner <david@fromorbit.com> > > --- > > configure.ac | 1 + > > include/builddefs.in | 1 + > > include/linux.h | 5 +++++ > > io/io.h | 1 + > > io/mmap.c | 19 ++++++++++++++----- > > m4/package_libcdev.m4 | 16 ++++++++++++++++ > > man/man8/xfs_io.8 | 6 +++++- > > 7 files changed, 43 insertions(+), 6 deletions(-) > > > > diff --git a/configure.ac b/configure.ac > > index cb23fb8..7153c9f 100644 > > --- a/configure.ac > > +++ b/configure.ac > > @@ -162,6 +162,7 @@ AC_HAVE_FSETXATTR > > AC_HAVE_MREMAP > > AC_NEED_INTERNAL_FSXATTR > > AC_HAVE_GETFSMAP > > +AC_HAVE_MAP_SYNC > > > > if test "$enable_blkid" = yes; then > > AC_HAVE_BLKID_TOPO > > diff --git a/include/builddefs.in b/include/builddefs.in > > index 1d454b6..78b71fe 100644 > > --- a/include/builddefs.in > > +++ b/include/builddefs.in > > @@ -114,6 +114,7 @@ HAVE_FSETXATTR = @have_fsetxattr@ > > HAVE_MREMAP = @have_mremap@ > > NEED_INTERNAL_FSXATTR = @need_internal_fsxattr@ > > HAVE_GETFSMAP = @have_getfsmap@ > > +HAVE_MAP_SYNC = @have_map_sync@ > > > > GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall > > # -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-decl > > diff --git a/include/linux.h b/include/linux.h > > index 6ce344c..4ee03ed 100644 > > --- a/include/linux.h > > +++ b/include/linux.h > > @@ -327,4 +327,9 @@ fsmap_advance( > > #define HAVE_GETFSMAP > > #endif /* HAVE_GETFSMAP */ > > > > +#ifndef HAVE_MAP_SYNC > > +#define MAP_SYNC 0x80000 > > Hmm, this is the x86 specific value of MAP_SYNC. I think it would be > better to define MAP_SYNC to zero in this case and check for MAP_SYNC > == 0 at run time. Ah, so instead of defining MAP_SYNC if the proper headers aren't installed, set to 0 and disallow the -S option? Fair enough.
On Fri, Nov 17, 2017 at 12:40:21PM -0800, Darrick J. Wong wrote: > On Fri, Nov 17, 2017 at 01:25:23PM -0700, Ross Zwisler wrote: > > Add support for a new -S flag to xfs_io's mmap command. This opens the > > mapping with the (MAP_SYNC | MAP_SHARED_VALIDATE) flags instead of the > > standard MAP_SHARED flag. > > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > > Suggested-by: Dave Chinner <david@fromorbit.com> > > --- <> > > diff --git a/include/linux.h b/include/linux.h > > index 6ce344c..4ee03ed 100644 > > --- a/include/linux.h > > +++ b/include/linux.h > > @@ -327,4 +327,9 @@ fsmap_advance( > > #define HAVE_GETFSMAP > > #endif /* HAVE_GETFSMAP */ > > > > +#ifndef HAVE_MAP_SYNC > > +#define MAP_SYNC 0x80000 > > +#define MAP_SHARED_VALIDATE 0x3 > > +#endif /* HAVE_MAP_SYNC */ > > Hmm, what's the point of ifndef/define if you have an configure.ac check? I'm following the example of HAVE_GETFSMAP. It does a check to see if the headers have proper support in m4/package_libcdev.m4, then has code in this file to provide defines if they aren't provided in the system. > > diff --git a/io/mmap.c b/io/mmap.c > > index 7a8150e..520b037 100644 > > --- a/io/mmap.c > > +++ b/io/mmap.c > > @@ -42,7 +42,7 @@ print_mapping( > > int index, > > int braces) > > { > > - unsigned char buffer[8] = { 0 }; > > + char buffer[8] = { 0 }; > > int i; > > > > static struct { > > @@ -57,6 +57,10 @@ print_mapping( > > > > for (i = 0, p = pflags; p->prot != PROT_NONE; i++, p++) > > buffer[i] = (map->prot & p->prot) ? p->mode : '-'; > > + > > + if (map->map_sync) > > + sprintf(&buffer[i], " S"); > > Does buffer need enlarging here? Nope. The buffer is 8 chars, and the 'rwx\0' string only uses 4. "rwx S\0" uses 6, so we're still good to go.
diff --git a/configure.ac b/configure.ac index cb23fb8..7153c9f 100644 --- a/configure.ac +++ b/configure.ac @@ -162,6 +162,7 @@ AC_HAVE_FSETXATTR AC_HAVE_MREMAP AC_NEED_INTERNAL_FSXATTR AC_HAVE_GETFSMAP +AC_HAVE_MAP_SYNC if test "$enable_blkid" = yes; then AC_HAVE_BLKID_TOPO diff --git a/include/builddefs.in b/include/builddefs.in index 1d454b6..78b71fe 100644 --- a/include/builddefs.in +++ b/include/builddefs.in @@ -114,6 +114,7 @@ HAVE_FSETXATTR = @have_fsetxattr@ HAVE_MREMAP = @have_mremap@ NEED_INTERNAL_FSXATTR = @need_internal_fsxattr@ HAVE_GETFSMAP = @have_getfsmap@ +HAVE_MAP_SYNC = @have_map_sync@ GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall # -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-decl diff --git a/include/linux.h b/include/linux.h index 6ce344c..4ee03ed 100644 --- a/include/linux.h +++ b/include/linux.h @@ -327,4 +327,9 @@ fsmap_advance( #define HAVE_GETFSMAP #endif /* HAVE_GETFSMAP */ +#ifndef HAVE_MAP_SYNC +#define MAP_SYNC 0x80000 +#define MAP_SHARED_VALIDATE 0x3 +#endif /* HAVE_MAP_SYNC */ + #endif /* __XFS_LINUX_H__ */ diff --git a/io/io.h b/io/io.h index 3862985..8b2753b 100644 --- a/io/io.h +++ b/io/io.h @@ -65,6 +65,7 @@ typedef struct mmap_region { size_t length; /* length of mapping */ off64_t offset; /* start offset into backing file */ int prot; /* protection mode of the mapping */ + bool map_sync; /* is this a MAP_SYNC mapping? */ char *name; /* name of backing file */ } mmap_region_t; diff --git a/io/mmap.c b/io/mmap.c index 7a8150e..520b037 100644 --- a/io/mmap.c +++ b/io/mmap.c @@ -42,7 +42,7 @@ print_mapping( int index, int braces) { - unsigned char buffer[8] = { 0 }; + char buffer[8] = { 0 }; int i; static struct { @@ -57,6 +57,10 @@ print_mapping( for (i = 0, p = pflags; p->prot != PROT_NONE; i++, p++) buffer[i] = (map->prot & p->prot) ? p->mode : '-'; + + if (map->map_sync) + sprintf(&buffer[i], " S"); + printf("%c%03d%c 0x%lx - 0x%lx %s %14s (%lld : %ld)\n", braces? '[' : ' ', index, braces? ']' : ' ', (unsigned long)map->addr, @@ -146,6 +150,7 @@ mmap_help(void) " -r -- map with PROT_READ protection\n" " -w -- map with PROT_WRITE protection\n" " -x -- map with PROT_EXEC protection\n" +" -S -- map with MAP_SHARED_VALIDATE and MAP_SYNC flags\n" " -s <size> -- first do mmap(size)/munmap(size), try to reserve some free space\n" " If no protection mode is specified, all are used by default.\n" "\n")); @@ -161,7 +166,7 @@ mmap_f( void *address = NULL; char *filename; size_t blocksize, sectsize; - int c, prot = 0; + int c, prot = 0, flags = MAP_SHARED; if (argc == 1) { if (mapping) @@ -184,7 +189,7 @@ mmap_f( init_cvtnum(&blocksize, §size); - while ((c = getopt(argc, argv, "rwxs:")) != EOF) { + while ((c = getopt(argc, argv, "rwxSs:")) != EOF) { switch (c) { case 'r': prot |= PROT_READ; @@ -195,6 +200,9 @@ mmap_f( case 'x': prot |= PROT_EXEC; break; + case 'S': + flags = MAP_SHARED_VALIDATE | MAP_SYNC; + break; case 's': length2 = cvtnum(blocksize, sectsize, optarg); break; @@ -238,7 +246,7 @@ mmap_f( MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); munmap(address, length2); } - address = mmap(address, length, prot, MAP_SHARED, file->fd, offset); + address = mmap(address, length, prot, flags, file->fd, offset); if (address == MAP_FAILED) { perror("mmap"); free(filename); @@ -263,6 +271,7 @@ mmap_f( mapping->offset = offset; mapping->name = filename; mapping->prot = prot; + mapping->map_sync = (flags == (MAP_SHARED_VALIDATE | MAP_SYNC)); return 0; } @@ -676,7 +685,7 @@ mmap_init(void) mmap_cmd.argmax = -1; mmap_cmd.flags = CMD_NOMAP_OK | CMD_NOFILE_OK | CMD_FOREIGN_OK | CMD_FLAG_ONESHOT; - mmap_cmd.args = _("[N] | [-rwx] [-s size] [off len]"); + mmap_cmd.args = _("[N] | [-rwxS] [-s size] [off len]"); mmap_cmd.oneline = _("mmap a range in the current file, show mappings"); mmap_cmd.help = mmap_help; diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4 index fdf9d69..598f5df 100644 --- a/m4/package_libcdev.m4 +++ b/m4/package_libcdev.m4 @@ -314,3 +314,19 @@ AC_DEFUN([AC_HAVE_GETFSMAP], AC_MSG_RESULT(no)) AC_SUBST(have_getfsmap) ]) + +# +# Check if we have MAP_SYNC defines (Linux) +# +AC_DEFUN([AC_HAVE_MAP_SYNC], + [ AC_MSG_CHECKING([for MAP_SYNC]) + AC_TRY_COMPILE([ +#include <asm-generic/mman.h> +#include <asm-generic/mman-common.h> + ], [ + int flags = MAP_SHARED_VALIDATE | MAP_SYNC; + ], have_map_sync=yes + AC_MSG_RESULT(yes), + AC_MSG_RESULT(no)) + AC_SUBST(have_map_sync) + ]) diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 index 9bf1a47..1693f7f 100644 --- a/man/man8/xfs_io.8 +++ b/man/man8/xfs_io.8 @@ -764,7 +764,7 @@ Each (sec, nsec) pair constitutes a single timestamp value. .SH MEMORY MAPPED I/O COMMANDS .TP -.BI "mmap [ " N " | [[ \-rwx ] [\-s " size " ] " "offset length " ]] +.BI "mmap [ " N " | [[ \-rwxS ] [\-s " size " ] " "offset length " ]] With no arguments, .B mmap shows the current mappings. Specifying a single numeric argument @@ -780,6 +780,10 @@ PROT_WRITE .RB ( \-w ), and PROT_EXEC .RB ( \-x ). +The mapping will be created with the MAP_SHARED flag by default, or with the +Linux specific (MAP_SYNC | MAP_SHARED_VALIDATE) flags if +.B -S +is given. .BI \-s " size" is used to do a mmap(size) && munmap(size) operation at first, try to reserve some extendible free memory space, if
Add support for a new -S flag to xfs_io's mmap command. This opens the mapping with the (MAP_SYNC | MAP_SHARED_VALIDATE) flags instead of the standard MAP_SHARED flag. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Suggested-by: Dave Chinner <david@fromorbit.com> --- configure.ac | 1 + include/builddefs.in | 1 + include/linux.h | 5 +++++ io/io.h | 1 + io/mmap.c | 19 ++++++++++++++----- m4/package_libcdev.m4 | 16 ++++++++++++++++ man/man8/xfs_io.8 | 6 +++++- 7 files changed, 43 insertions(+), 6 deletions(-)