| Message ID | 149098153785.28108.1114055429564367803.stgit@warthog.procyon.org.uk |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Fri, Mar 31, 2017 at 06:32:17PM +0100, David Howells wrote: > Include a mask in struct stat to indicate which bits of stx_attributes the > filesystem actually supports. > > This would also be useful if we add another system call that allows you to > do a 'bulk attribute set' and pass in a statx struct with the masks > appropriately set to say what you want to set. > > Signed-off-by: David Howells <dhowells@redhat.com> > --- > > fs/ext4/inode.c | 6 ++++++ > fs/stat.c | 1 + > include/linux/stat.h | 1 + > include/uapi/linux/stat.h | 4 ++-- > samples/statx/test-statx.c | 12 ++++++++---- > 5 files changed, 18 insertions(+), 6 deletions(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 5d02b922afa3..349f97ae3c87 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -5413,6 +5413,12 @@ int ext4_getattr(const struct path *path, struct kstat *stat, > if (flags & EXT4_NODUMP_FL) > stat->attributes |= STATX_ATTR_NODUMP; > > + stat->attributes_mask |= (STATX_ATTR_APPEND | > + STATX_ATTR_COMPRESSED | ext4 doesn't actually support compressed files. (I know, the feature/inode flags exist, but there's no code and afaik probably never will be...) --D > + STATX_ATTR_ENCRYPTED | > + STATX_ATTR_IMMUTABLE | > + STATX_ATTR_NODUMP); > + > generic_fillattr(inode, stat); > return 0; > } > diff --git a/fs/stat.c b/fs/stat.c > index 0c7e6cdc435c..c6c963b2546b 100644 > --- a/fs/stat.c > +++ b/fs/stat.c > @@ -527,6 +527,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer) > tmp.stx_ino = stat->ino; > tmp.stx_size = stat->size; > tmp.stx_blocks = stat->blocks; > + tmp.stx_attributes_mask = stat->attributes_mask; > tmp.stx_atime.tv_sec = stat->atime.tv_sec; > tmp.stx_atime.tv_nsec = stat->atime.tv_nsec; > tmp.stx_btime.tv_sec = stat->btime.tv_sec; > diff --git a/include/linux/stat.h b/include/linux/stat.h > index c76e524fb34b..64b6b3aece21 100644 > --- a/include/linux/stat.h > +++ b/include/linux/stat.h > @@ -26,6 +26,7 @@ struct kstat { > unsigned int nlink; > uint32_t blksize; /* Preferred I/O size */ > u64 attributes; > + u64 attributes_mask; > #define KSTAT_ATTR_FS_IOC_FLAGS \ > (STATX_ATTR_COMPRESSED | \ > STATX_ATTR_IMMUTABLE | \ > diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h > index 0869b9eaa8ce..d538897b8e08 100644 > --- a/include/uapi/linux/stat.h > +++ b/include/uapi/linux/stat.h > @@ -114,7 +114,7 @@ struct statx { > __u64 stx_ino; /* Inode number */ > __u64 stx_size; /* File size */ > __u64 stx_blocks; /* Number of 512-byte blocks allocated */ > - __u64 __spare1[1]; > + __u64 stx_attributes_mask; /* Mask to show what's supported in stx_attributes */ > /* 0x40 */ > struct statx_timestamp stx_atime; /* Last access time */ > struct statx_timestamp stx_btime; /* File creation time */ > @@ -155,7 +155,7 @@ struct statx { > #define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */ > > /* > - * Attributes to be found in stx_attributes > + * Attributes to be found in stx_attributes and masked in stx_attributes_mask. > * > * These give information about the features or the state of a file that might > * be of use to ordinary userspace programs such as GUIs or ls rather than > diff --git a/samples/statx/test-statx.c b/samples/statx/test-statx.c > index 8571d766331d..d4d77b09412c 100644 > --- a/samples/statx/test-statx.c > +++ b/samples/statx/test-statx.c > @@ -141,8 +141,8 @@ static void dump_statx(struct statx *stx) > if (stx->stx_mask & STATX_BTIME) > print_time(" Birth: ", &stx->stx_btime); > > - if (stx->stx_attributes) { > - unsigned char bits; > + if (stx->stx_attributes_mask) { > + unsigned char bits, mbits; > int loop, byte; > > static char attr_representation[64 + 1] = > @@ -160,14 +160,18 @@ static void dump_statx(struct statx *stx) > printf("Attributes: %016llx (", stx->stx_attributes); > for (byte = 64 - 8; byte >= 0; byte -= 8) { > bits = stx->stx_attributes >> byte; > + mbits = stx->stx_attributes_mask >> byte; > for (loop = 7; loop >= 0; loop--) { > int bit = byte + loop; > > - if (bits & 0x80) > + if (!(mbits & 0x80)) > + putchar('.'); /* Not supported */ > + else if (bits & 0x80) > putchar(attr_representation[63 - bit]); > else > - putchar('-'); > + putchar('-'); /* Not set */ > bits <<= 1; > + mbits <<= 1; > } > if (byte) > putchar(' '); > > -- > 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, Mar 31, 2017 at 06:32:17PM +0100, David Howells wrote: > Include a mask in struct stat to indicate which bits of stx_attributes the > filesystem actually supports. What's the use case for this?
On Tue, Apr 04, 2017 at 12:12:52AM -0700, Christoph Hellwig wrote: > On Fri, Mar 31, 2017 at 06:32:17PM +0100, David Howells wrote: > > Include a mask in struct stat to indicate which bits of stx_attributes the > > filesystem actually supports. > > What's the use case for this? ping!
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 5d02b922afa3..349f97ae3c87 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5413,6 +5413,12 @@ int ext4_getattr(const struct path *path, struct kstat *stat, if (flags & EXT4_NODUMP_FL) stat->attributes |= STATX_ATTR_NODUMP; + stat->attributes_mask |= (STATX_ATTR_APPEND | + STATX_ATTR_COMPRESSED | + STATX_ATTR_ENCRYPTED | + STATX_ATTR_IMMUTABLE | + STATX_ATTR_NODUMP); + generic_fillattr(inode, stat); return 0; } diff --git a/fs/stat.c b/fs/stat.c index 0c7e6cdc435c..c6c963b2546b 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -527,6 +527,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer) tmp.stx_ino = stat->ino; tmp.stx_size = stat->size; tmp.stx_blocks = stat->blocks; + tmp.stx_attributes_mask = stat->attributes_mask; tmp.stx_atime.tv_sec = stat->atime.tv_sec; tmp.stx_atime.tv_nsec = stat->atime.tv_nsec; tmp.stx_btime.tv_sec = stat->btime.tv_sec; diff --git a/include/linux/stat.h b/include/linux/stat.h index c76e524fb34b..64b6b3aece21 100644 --- a/include/linux/stat.h +++ b/include/linux/stat.h @@ -26,6 +26,7 @@ struct kstat { unsigned int nlink; uint32_t blksize; /* Preferred I/O size */ u64 attributes; + u64 attributes_mask; #define KSTAT_ATTR_FS_IOC_FLAGS \ (STATX_ATTR_COMPRESSED | \ STATX_ATTR_IMMUTABLE | \ diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h index 0869b9eaa8ce..d538897b8e08 100644 --- a/include/uapi/linux/stat.h +++ b/include/uapi/linux/stat.h @@ -114,7 +114,7 @@ struct statx { __u64 stx_ino; /* Inode number */ __u64 stx_size; /* File size */ __u64 stx_blocks; /* Number of 512-byte blocks allocated */ - __u64 __spare1[1]; + __u64 stx_attributes_mask; /* Mask to show what's supported in stx_attributes */ /* 0x40 */ struct statx_timestamp stx_atime; /* Last access time */ struct statx_timestamp stx_btime; /* File creation time */ @@ -155,7 +155,7 @@ struct statx { #define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */ /* - * Attributes to be found in stx_attributes + * Attributes to be found in stx_attributes and masked in stx_attributes_mask. * * These give information about the features or the state of a file that might * be of use to ordinary userspace programs such as GUIs or ls rather than diff --git a/samples/statx/test-statx.c b/samples/statx/test-statx.c index 8571d766331d..d4d77b09412c 100644 --- a/samples/statx/test-statx.c +++ b/samples/statx/test-statx.c @@ -141,8 +141,8 @@ static void dump_statx(struct statx *stx) if (stx->stx_mask & STATX_BTIME) print_time(" Birth: ", &stx->stx_btime); - if (stx->stx_attributes) { - unsigned char bits; + if (stx->stx_attributes_mask) { + unsigned char bits, mbits; int loop, byte; static char attr_representation[64 + 1] = @@ -160,14 +160,18 @@ static void dump_statx(struct statx *stx) printf("Attributes: %016llx (", stx->stx_attributes); for (byte = 64 - 8; byte >= 0; byte -= 8) { bits = stx->stx_attributes >> byte; + mbits = stx->stx_attributes_mask >> byte; for (loop = 7; loop >= 0; loop--) { int bit = byte + loop; - if (bits & 0x80) + if (!(mbits & 0x80)) + putchar('.'); /* Not supported */ + else if (bits & 0x80) putchar(attr_representation[63 - bit]); else - putchar('-'); + putchar('-'); /* Not set */ bits <<= 1; + mbits <<= 1; } if (byte) putchar(' ');
Include a mask in struct stat to indicate which bits of stx_attributes the filesystem actually supports. This would also be useful if we add another system call that allows you to do a 'bulk attribute set' and pass in a statx struct with the masks appropriately set to say what you want to set. Signed-off-by: David Howells <dhowells@redhat.com> --- fs/ext4/inode.c | 6 ++++++ fs/stat.c | 1 + include/linux/stat.h | 1 + include/uapi/linux/stat.h | 4 ++-- samples/statx/test-statx.c | 12 ++++++++---- 5 files changed, 18 insertions(+), 6 deletions(-)