2014-06-19 23:15:27

by Eric Sandeen

[permalink] [raw]
Subject: [PATCH 1/2] e2fsprogs: reorder flags in chattr(1)

The flags described in chattr usage() and the chattr(1) manpage
were in semi-random order, which makes it hard to ascertain
which flags might be missing or undocumented, and to locate
flags within the manpage.

Re-order the list of flags in alphanumeric order, and do
the same for the flag descriptions in the body of the manpage.

There should be no content changes here, just reordering
for consistency.

Signed-off-by: Eric Sandeen <[email protected]>
---

diff --git a/misc/chattr.1.in b/misc/chattr.1.in
index 2a3640c..ce426e8 100644
--- a/misc/chattr.1.in
+++ b/misc/chattr.1.in
@@ -19,24 +19,36 @@ chattr \- change file attributes on a Linux file system
.B chattr
changes the file attributes on a Linux file system.
.PP
-The format of a symbolic mode is +-=[acdeijstuACDST].
+The format of a symbolic mode is +-=[aAcCdDeijsStTu].
.PP
The operator `+' causes the selected attributes to be added to the
existing attributes of the files; `-' causes them to be removed; and
`=' causes them to be the only attributes that the files have.
.PP
-The letters `acdeijstuACDST' select the new attributes for the files:
-append only (a), compressed (c), no dump (d), extent format (e), immutable (i),
-data journalling (j), secure deletion (s), no tail-merging (t),
-undeletable (u), no atime updates (A), no copy on write (C),
-synchronous directory updates (D), synchronous updates (S),
-and top of directory hierarchy (T).
+The letters `aAcCdDeijsStTu' select the new attributes for the files:
+append only (a),
+no atime updates (A),
+compressed (c),
+no copy on write (C),
+no dump (d),
+synchronous directory updates (D),
+extent format (e),
+immutable (i),
+data journalling (j),
+secure deletion (s),
+synchronous updates (S),
+no tail-merging (t),
+top of directory hierarchy (T),
+and undeletable (u).
.PP
The following attributes are read-only, and may be listed by
.BR lsattr (1)
-but not modified by chattr: huge file (h), compression error (E),
-indexed directory (I), compression raw access (X), and compressed dirty
-file (Z).
+but not modified by chattr:
+compression error (E),
+huge file (h),
+indexed directory (I),
+compression raw access (X),
+and compressed dirty file (Z).
.SH OPTIONS
.TP
.B \-R
@@ -51,14 +63,14 @@ Suppress most error messages.
.BI \-v " version"
Set the file's version/generation number.
.SH ATTRIBUTES
-When a file with the 'A' attribute set is accessed, its atime record is
-not modified. This avoids a certain amount of disk I/O for laptop
-systems.
-.PP
A file with the `a' attribute set can only be open in append mode for writing.
Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
capability can set or clear this attribute.
.PP
+When a file with the 'A' attribute set is accessed, its atime record is
+not modified. This avoids a certain amount of disk I/O for laptop
+systems.
+.PP
A file with the `c' attribute set is automatically compressed on the disk
by the kernel. A read from this file returns uncompressed data. A write to
this file compresses data before storing them on the disk. Note: please
@@ -74,27 +86,21 @@ be fully stable. If the 'C' flag is set on a directory, it will have no
effect on the directory, but new files created in that directory will
the No_COW attribute.)
.PP
-When a directory with the `D' attribute set is modified,
-the changes are written synchronously on the disk; this is equivalent to
-the `dirsync' mount option applied to a subset of the files.
-.PP
A file with the `d' attribute set is not candidate for backup when the
.BR dump (8)
program is run.
.PP
-The 'E' attribute is used by the experimental compression patches to
-indicate that a compressed file has a compression error. It may not be
-set or reset using
-.BR chattr (1),
-although it can be displayed by
-.BR lsattr (1).
+When a directory with the `D' attribute set is modified,
+the changes are written synchronously on the disk; this is equivalent to
+the `dirsync' mount option applied to a subset of the files.
.PP
The 'e' attribute indicates that the file is using extents for mapping
the blocks on disk. It may not be removed using
.BR chattr (1).
.PP
-The 'I' attribute is used by the htree code to indicate that a directory
-is being indexed using hashed trees. It may not be set or reset using
+The 'E' attribute is used by the experimental compression patches to
+indicate that a compressed file has a compression error. It may not be
+set or reset using
.BR chattr (1),
although it can be displayed by
.BR lsattr (1).
@@ -111,6 +117,12 @@ renamed, no link can be created to this file and no data can be written
to the file. Only the superuser or a process possessing the
CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
.PP
+The 'I' attribute is used by the htree code to indicate that a directory
+is being indexed using hashed trees. It may not be set or reset using
+.BR chattr (1),
+although it can be displayed by
+.BR lsattr (1).
+.PP
A file with the `j' attribute has all of its data written to the ext3
or ext4 journal before being written to the file itself, if the filesystem
is mounted with the "data=ordered" or "data=writeback" options. When the
@@ -127,6 +139,13 @@ When a file with the `S' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
the `sync' mount option applied to a subset of the files.
.PP
+A file with the 't' attribute will not have a partial block fragment at
+the end of the file merged with other files (for those filesystems which
+support tail-merging). This is necessary for applications such as LILO
+which read the filesystem directly, and which don't understand tail-merged
+files. Note: As of this writing, the ext2 or ext3 filesystems do not
+(yet, except in very experimental patches) support tail-merging.
+.PP
A directory with the 'T' attribute will be deemed to be the top of
directory hierarchies for the purposes of the Orlov block allocator.
This is a hint to the block allocator used by ext3 and ext4 that the
@@ -137,13 +156,6 @@ and /home/mary are placed into separate block groups. For directories
where this attribute is not set, the Orlov block allocator will try to
group subdirectories closer together where possible.
.PP
-A file with the 't' attribute will not have a partial block fragment at
-the end of the file merged with other files (for those filesystems which
-support tail-merging). This is necessary for applications such as LILO
-which read the filesystem directly, and which don't understand tail-merged
-files. Note: As of this writing, the ext2 or ext3 filesystems do not
-(yet, except in very experimental patches) support tail-merging.
-.PP
When a file with the `u' attribute set is deleted, its contents are
saved. This allows the user to ask for its undeletion. Note: please
make sure to read the bugs and limitations section at the end of this

diff --git a/misc/chattr.c b/misc/chattr.c
index 39a6016..d2ae10f 100644
--- a/misc/chattr.c
+++ b/misc/chattr.c
@@ -84,6 +84,7 @@ static void usage(void)
{
fprintf(stderr,
_("Usage: %s [-RVf] [-+=AaCcDdeijsSu] [-v version] files...\n"),
+ _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
program_name);
exit(1);
}



2014-06-19 23:17:50

by Eric Sandeen

[permalink] [raw]
Subject: [PATCH 1/2 V2] e2fsprogs: reorder flags in chattr(1)

The flags described in chattr usage() and the chattr(1) manpage
were in semi-random order, which makes it hard to ascertain
which flags might be missing or undocumented, and to locate
flags within the manpage.

Re-order the list of flags in alphanumeric order, and do
the same for the flag descriptions in the body of the manpage.

There should be no content changes here, just reordering
for consistency.

Signed-off-by: Eric Sandeen <[email protected]>
---

V2: remove duplicate line in usage()!
(why do I only spot these things immediately after I hit send?)

diff --git a/misc/chattr.1.in b/misc/chattr.1.in
index 2a3640c..ce426e8 100644
--- a/misc/chattr.1.in
+++ b/misc/chattr.1.in
@@ -19,24 +19,36 @@ chattr \- change file attributes on a Linux file system
.B chattr
changes the file attributes on a Linux file system.
.PP
-The format of a symbolic mode is +-=[acdeijstuACDST].
+The format of a symbolic mode is +-=[aAcCdDeijsStTu].
.PP
The operator `+' causes the selected attributes to be added to the
existing attributes of the files; `-' causes them to be removed; and
`=' causes them to be the only attributes that the files have.
.PP
-The letters `acdeijstuACDST' select the new attributes for the files:
-append only (a), compressed (c), no dump (d), extent format (e), immutable (i),
-data journalling (j), secure deletion (s), no tail-merging (t),
-undeletable (u), no atime updates (A), no copy on write (C),
-synchronous directory updates (D), synchronous updates (S),
-and top of directory hierarchy (T).
+The letters `aAcCdDeijsStTu' select the new attributes for the files:
+append only (a),
+no atime updates (A),
+compressed (c),
+no copy on write (C),
+no dump (d),
+synchronous directory updates (D),
+extent format (e),
+immutable (i),
+data journalling (j),
+secure deletion (s),
+synchronous updates (S),
+no tail-merging (t),
+top of directory hierarchy (T),
+and undeletable (u).
.PP
The following attributes are read-only, and may be listed by
.BR lsattr (1)
-but not modified by chattr: huge file (h), compression error (E),
-indexed directory (I), compression raw access (X), and compressed dirty
-file (Z).
+but not modified by chattr:
+compression error (E),
+huge file (h),
+indexed directory (I),
+compression raw access (X),
+and compressed dirty file (Z).
.SH OPTIONS
.TP
.B \-R
@@ -51,14 +63,14 @@ Suppress most error messages.
.BI \-v " version"
Set the file's version/generation number.
.SH ATTRIBUTES
-When a file with the 'A' attribute set is accessed, its atime record is
-not modified. This avoids a certain amount of disk I/O for laptop
-systems.
-.PP
A file with the `a' attribute set can only be open in append mode for writing.
Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
capability can set or clear this attribute.
.PP
+When a file with the 'A' attribute set is accessed, its atime record is
+not modified. This avoids a certain amount of disk I/O for laptop
+systems.
+.PP
A file with the `c' attribute set is automatically compressed on the disk
by the kernel. A read from this file returns uncompressed data. A write to
this file compresses data before storing them on the disk. Note: please
@@ -74,27 +86,21 @@ be fully stable. If the 'C' flag is set on a directory, it will have no
effect on the directory, but new files created in that directory will
the No_COW attribute.)
.PP
-When a directory with the `D' attribute set is modified,
-the changes are written synchronously on the disk; this is equivalent to
-the `dirsync' mount option applied to a subset of the files.
-.PP
A file with the `d' attribute set is not candidate for backup when the
.BR dump (8)
program is run.
.PP
-The 'E' attribute is used by the experimental compression patches to
-indicate that a compressed file has a compression error. It may not be
-set or reset using
-.BR chattr (1),
-although it can be displayed by
-.BR lsattr (1).
+When a directory with the `D' attribute set is modified,
+the changes are written synchronously on the disk; this is equivalent to
+the `dirsync' mount option applied to a subset of the files.
.PP
The 'e' attribute indicates that the file is using extents for mapping
the blocks on disk. It may not be removed using
.BR chattr (1).
.PP
-The 'I' attribute is used by the htree code to indicate that a directory
-is being indexed using hashed trees. It may not be set or reset using
+The 'E' attribute is used by the experimental compression patches to
+indicate that a compressed file has a compression error. It may not be
+set or reset using
.BR chattr (1),
although it can be displayed by
.BR lsattr (1).
@@ -111,6 +117,12 @@ renamed, no link can be created to this file and no data can be written
to the file. Only the superuser or a process possessing the
CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
.PP
+The 'I' attribute is used by the htree code to indicate that a directory
+is being indexed using hashed trees. It may not be set or reset using
+.BR chattr (1),
+although it can be displayed by
+.BR lsattr (1).
+.PP
A file with the `j' attribute has all of its data written to the ext3
or ext4 journal before being written to the file itself, if the filesystem
is mounted with the "data=ordered" or "data=writeback" options. When the
@@ -127,6 +139,13 @@ When a file with the `S' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
the `sync' mount option applied to a subset of the files.
.PP
+A file with the 't' attribute will not have a partial block fragment at
+the end of the file merged with other files (for those filesystems which
+support tail-merging). This is necessary for applications such as LILO
+which read the filesystem directly, and which don't understand tail-merged
+files. Note: As of this writing, the ext2 or ext3 filesystems do not
+(yet, except in very experimental patches) support tail-merging.
+.PP
A directory with the 'T' attribute will be deemed to be the top of
directory hierarchies for the purposes of the Orlov block allocator.
This is a hint to the block allocator used by ext3 and ext4 that the
@@ -137,13 +156,6 @@ and /home/mary are placed into separate block groups. For directories
where this attribute is not set, the Orlov block allocator will try to
group subdirectories closer together where possible.
.PP
-A file with the 't' attribute will not have a partial block fragment at
-the end of the file merged with other files (for those filesystems which
-support tail-merging). This is necessary for applications such as LILO
-which read the filesystem directly, and which don't understand tail-merged
-files. Note: As of this writing, the ext2 or ext3 filesystems do not
-(yet, except in very experimental patches) support tail-merging.
-.PP
When a file with the `u' attribute set is deleted, its contents are
saved. This allows the user to ask for its undeletion. Note: please
make sure to read the bugs and limitations section at the end of this
diff --git a/misc/chattr.c b/misc/chattr.c
index 39a6016..d5a6a61 100644
--- a/misc/chattr.c
+++ b/misc/chattr.c
@@ -83,7 +83,7 @@ static unsigned long sf;
static void usage(void)
{
fprintf(stderr,
- _("Usage: %s [-RVf] [-+=AaCcDdeijsSu] [-v version] files...\n"),
+ _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
program_name);
exit(1);
}


2014-06-19 23:24:26

by Eric Sandeen

[permalink] [raw]
Subject: [PATCH 2/2] e2fsprogs: revise and extend chattr(1) and chattr usage()

The chattr(1) manpage and chattr usage() output were missing some flags.

Add those, and make some other minor cosmetic fixes.

(I've left out the 'B' (EXT2_COMPRBLK_FL) flag, because
it's not actually used anywhere, and I can't figure out
how it differs from 'c' (EXT2_COMPR_FL))

Also, because the matrix of filesystems & flags is quite large,
refer to filesystem-specific manpages for detailed discussion
of flags supported by those filesystems, rather than trying to
cover it all in this manpage. I'll send those manpage
updates to the appropriate lists a bit later.

Signed-off-by: Eric Sandeen <[email protected]>
---

diff --git a/misc/chattr.1.in b/misc/chattr.1.in
index ce426e8..6f64e09 100644
--- a/misc/chattr.1.in
+++ b/misc/chattr.1.in
@@ -47,8 +47,17 @@ but not modified by chattr:
compression error (E),
huge file (h),
indexed directory (I),
+inline data (N),
compression raw access (X),
and compressed dirty file (Z).
+.PP
+Not all flags are supported or utilized by all filesystems; refer to
+filesystem-specific man pages such as
+.BR btrfs (5),
+.BR ext4 (5),
+and
+.BR xfs (5)
+for more filesystem-specific details.
.SH OPTIONS
.TP
.B \-R
@@ -67,7 +76,7 @@ A file with the `a' attribute set can only be open in append mode for writing.
Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
capability can set or clear this attribute.
.PP
-When a file with the 'A' attribute set is accessed, its atime record is
+When a file with the `A' attribute set is accessed, its atime record is
not modified. This avoids a certain amount of disk I/O for laptop
systems.
.PP
@@ -77,12 +86,12 @@ this file compresses data before storing them on the disk. Note: please
make sure to read the bugs and limitations section at the end of this
document.
.PP
-A file with the 'C' attribute set will not be subject to copy-on-write
+A file with the `C' attribute set will not be subject to copy-on-write
updates. This flag is only supported on file systems which perform
-copy-on-write. (Note: For btrfs, the 'C' flag should be
+copy-on-write. (Note: For btrfs, the `C' flag should be
set on new or empty files. If it is set on a file which already has
data blocks, it is undefined when the blocks assigned to the file will
-be fully stable. If the 'C' flag is set on a directory, it will have no
+be fully stable. If the `C' flag is set on a directory, it will have no
effect on the directory, but new files created in that directory will
the No_COW attribute.)
.PP
@@ -94,18 +103,18 @@ When a directory with the `D' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
the `dirsync' mount option applied to a subset of the files.
.PP
-The 'e' attribute indicates that the file is using extents for mapping
+The `e' attribute indicates that the file is using extents for mapping
the blocks on disk. It may not be removed using
.BR chattr (1).
.PP
-The 'E' attribute is used by the experimental compression patches to
+The `E' attribute is used by the experimental compression patches to
indicate that a compressed file has a compression error. It may not be
set or reset using
.BR chattr (1),
although it can be displayed by
.BR lsattr (1).
.PP
-The 'h' attribute indicates the file is storing its blocks in units of the
+The `h' attribute indicates the file is storing its blocks in units of the
filesystem blocksize instead of in units of sectors, and means that the file
is (or at one time was) larger than 2TB. It may not be set or reset using
.BR chattr (1),
@@ -117,7 +126,7 @@ renamed, no link can be created to this file and no data can be written
to the file. Only the superuser or a process possessing the
CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
.PP
-The 'I' attribute is used by the htree code to indicate that a directory
+The `I' attribute is used by the htree code to indicate that a directory
is being indexed using hashed trees. It may not be set or reset using
.BR chattr (1),
although it can be displayed by
@@ -131,6 +140,12 @@ is already journalled and this attribute has no effect. Only
the superuser or a process possessing the CAP_SYS_RESOURCE
capability can set or clear this attribute.
.PP
+A file with the `N' attribute set indicates that the file has data
+stored inline, within the inode itself. It may not be set or reset using
+.BR chattr (1),
+although it can be displayed by
+.BR lsattr (1).
+.PP
When a file with the `s' attribute set is deleted, its blocks are zeroed
and written back to the disk. Note: please make sure to read the bugs
and limitations section at the end of this document.
@@ -139,19 +154,19 @@ When a file with the `S' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
the `sync' mount option applied to a subset of the files.
.PP
-A file with the 't' attribute will not have a partial block fragment at
+A file with the `t' attribute will not have a partial block fragment at
the end of the file merged with other files (for those filesystems which
support tail-merging). This is necessary for applications such as LILO
which read the filesystem directly, and which don't understand tail-merged
files. Note: As of this writing, the ext2 or ext3 filesystems do not
(yet, except in very experimental patches) support tail-merging.
.PP
-A directory with the 'T' attribute will be deemed to be the top of
+A directory with the `T' attribute will be deemed to be the top of
directory hierarchies for the purposes of the Orlov block allocator.
This is a hint to the block allocator used by ext3 and ext4 that the
subdirectories under this directory are not related, and thus should be
spread apart for allocation purposes. For example it is a very good
-idea to set the 'T' attribute on the /home directory, so that /home/john
+idea to set the `T' attribute on the /home directory, so that /home/john
and /home/mary are placed into separate block groups. For directories
where this attribute is not set, the Orlov block allocator will try to
group subdirectories closer together where possible.
@@ -161,14 +176,14 @@ saved. This allows the user to ask for its undeletion. Note: please
make sure to read the bugs and limitations section at the end of this
document.
.PP
-The 'X' attribute is used by the experimental compression patches to
-indicate that a raw contents of a compressed file can be accessed
+The `X' attribute is used by the experimental compression patches to
+indicate that the raw contents of a compressed file can be accessed
directly. It currently may not be set or reset using
.BR chattr (1),
although it can be displayed by
.BR lsattr (1).
.PP
-The 'Z' attribute is used by the experimental compression patches to
+The `Z' attribute is used by the experimental compression patches to
indicate a compressed file is dirty. It may not be set or reset using
.BR chattr (1),
although it can be displayed by
@@ -179,7 +194,7 @@ although it can be displayed by
was written by Remy Card <[email protected]>. It is currently being
maintained by Theodore Ts'o <[email protected]>.
.SH BUGS AND LIMITATIONS
-The `c', 's', and `u' attributes are not honored
+The `c', `s', and `u' attributes are not honored
by the ext2, ext3, and ext4 filesystems as implemented in the current
mainline Linux kernels.
.PP
@@ -191,4 +206,7 @@ The `D' option is only useful on Linux kernel 2.5.19 and later.
is part of the e2fsprogs package and is available from
http://e2fsprogs.sourceforge.net.
.SH SEE ALSO
-.BR lsattr (1)
+.BR lsattr (1),
+.BR btrfs (5),
+.BR ext4 (5),
+.BR xfs (5).
diff --git a/misc/chattr.c b/misc/chattr.c
index d5a6a61..f130108 100644
--- a/misc/chattr.c
+++ b/misc/chattr.c
@@ -83,7 +83,7 @@ static unsigned long sf;
static void usage(void)
{
fprintf(stderr,
- _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
+ _("Usage: %s [-RVf] [-+=aAcCdDeijsStTu] [-v version] files...\n"),
program_name);
exit(1);
}



2014-06-20 05:27:06

by Andreas Dilger

[permalink] [raw]
Subject: Re: [PATCH 2/2] e2fsprogs: revise and extend chattr(1) and chattr usage()

Please don't do the "use backtick "`" as opening quote for single quote "'" trick" that the GNU utils just stopped doing. I don't think this improves readability, and it makes syntax highlighting tools unhappy since there are imbalanced quotes.

Cheers, Andreas

> On Jun 19, 2014, at 17:24, Eric Sandeen <[email protected]> wrote:
>
> The chattr(1) manpage and chattr usage() output were missing some flags.
>
> Add those, and make some other minor cosmetic fixes.
>
> (I've left out the 'B' (EXT2_COMPRBLK_FL) flag, because
> it's not actually used anywhere, and I can't figure out
> how it differs from 'c' (EXT2_COMPR_FL))
>
> Also, because the matrix of filesystems & flags is quite large,
> refer to filesystem-specific manpages for detailed discussion
> of flags supported by those filesystems, rather than trying to
> cover it all in this manpage. I'll send those manpage
> updates to the appropriate lists a bit later.
>
> Signed-off-by: Eric Sandeen <[email protected]>
> ---
>
> diff --git a/misc/chattr.1.in b/misc/chattr.1.in
> index ce426e8..6f64e09 100644
> --- a/misc/chattr.1.in
> +++ b/misc/chattr.1.in
> @@ -47,8 +47,17 @@ but not modified by chattr:
> compression error (E),
> huge file (h),
> indexed directory (I),
> +inline data (N),
> compression raw access (X),
> and compressed dirty file (Z).
> +.PP
> +Not all flags are supported or utilized by all filesystems; refer to
> +filesystem-specific man pages such as
> +.BR btrfs (5),
> +.BR ext4 (5),
> +and
> +.BR xfs (5)
> +for more filesystem-specific details.
> .SH OPTIONS
> .TP
> .B \-R
> @@ -67,7 +76,7 @@ A file with the `a' attribute set can only be open in append mode for writing.
> Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
> capability can set or clear this attribute.
> .PP
> -When a file with the 'A' attribute set is accessed, its atime record is
> +When a file with the `A' attribute set is accessed, its atime record is
> not modified. This avoids a certain amount of disk I/O for laptop
> systems.
> .PP
> @@ -77,12 +86,12 @@ this file compresses data before storing them on the disk. Note: please
> make sure to read the bugs and limitations section at the end of this
> document.
> .PP
> -A file with the 'C' attribute set will not be subject to copy-on-write
> +A file with the `C' attribute set will not be subject to copy-on-write
> updates. This flag is only supported on file systems which perform
> -copy-on-write. (Note: For btrfs, the 'C' flag should be
> +copy-on-write. (Note: For btrfs, the `C' flag should be
> set on new or empty files. If it is set on a file which already has
> data blocks, it is undefined when the blocks assigned to the file will
> -be fully stable. If the 'C' flag is set on a directory, it will have no
> +be fully stable. If the `C' flag is set on a directory, it will have no
> effect on the directory, but new files created in that directory will
> the No_COW attribute.)
> .PP
> @@ -94,18 +103,18 @@ When a directory with the `D' attribute set is modified,
> the changes are written synchronously on the disk; this is equivalent to
> the `dirsync' mount option applied to a subset of the files.
> .PP
> -The 'e' attribute indicates that the file is using extents for mapping
> +The `e' attribute indicates that the file is using extents for mapping
> the blocks on disk. It may not be removed using
> .BR chattr (1).
> .PP
> -The 'E' attribute is used by the experimental compression patches to
> +The `E' attribute is used by the experimental compression patches to
> indicate that a compressed file has a compression error. It may not be
> set or reset using
> .BR chattr (1),
> although it can be displayed by
> .BR lsattr (1).
> .PP
> -The 'h' attribute indicates the file is storing its blocks in units of the
> +The `h' attribute indicates the file is storing its blocks in units of the
> filesystem blocksize instead of in units of sectors, and means that the file
> is (or at one time was) larger than 2TB. It may not be set or reset using
> .BR chattr (1),
> @@ -117,7 +126,7 @@ renamed, no link can be created to this file and no data can be written
> to the file. Only the superuser or a process possessing the
> CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
> .PP
> -The 'I' attribute is used by the htree code to indicate that a directory
> +The `I' attribute is used by the htree code to indicate that a directory
> is being indexed using hashed trees. It may not be set or reset using
> .BR chattr (1),
> although it can be displayed by
> @@ -131,6 +140,12 @@ is already journalled and this attribute has no effect. Only
> the superuser or a process possessing the CAP_SYS_RESOURCE
> capability can set or clear this attribute.
> .PP
> +A file with the `N' attribute set indicates that the file has data
> +stored inline, within the inode itself. It may not be set or reset using
> +.BR chattr (1),
> +although it can be displayed by
> +.BR lsattr (1).
> +.PP
> When a file with the `s' attribute set is deleted, its blocks are zeroed
> and written back to the disk. Note: please make sure to read the bugs
> and limitations section at the end of this document.
> @@ -139,19 +154,19 @@ When a file with the `S' attribute set is modified,
> the changes are written synchronously on the disk; this is equivalent to
> the `sync' mount option applied to a subset of the files.
> .PP
> -A file with the 't' attribute will not have a partial block fragment at
> +A file with the `t' attribute will not have a partial block fragment at
> the end of the file merged with other files (for those filesystems which
> support tail-merging). This is necessary for applications such as LILO
> which read the filesystem directly, and which don't understand tail-merged
> files. Note: As of this writing, the ext2 or ext3 filesystems do not
> (yet, except in very experimental patches) support tail-merging.
> .PP
> -A directory with the 'T' attribute will be deemed to be the top of
> +A directory with the `T' attribute will be deemed to be the top of
> directory hierarchies for the purposes of the Orlov block allocator.
> This is a hint to the block allocator used by ext3 and ext4 that the
> subdirectories under this directory are not related, and thus should be
> spread apart for allocation purposes. For example it is a very good
> -idea to set the 'T' attribute on the /home directory, so that /home/john
> +idea to set the `T' attribute on the /home directory, so that /home/john
> and /home/mary are placed into separate block groups. For directories
> where this attribute is not set, the Orlov block allocator will try to
> group subdirectories closer together where possible.
> @@ -161,14 +176,14 @@ saved. This allows the user to ask for its undeletion. Note: please
> make sure to read the bugs and limitations section at the end of this
> document.
> .PP
> -The 'X' attribute is used by the experimental compression patches to
> -indicate that a raw contents of a compressed file can be accessed
> +The `X' attribute is used by the experimental compression patches to
> +indicate that the raw contents of a compressed file can be accessed
> directly. It currently may not be set or reset using
> .BR chattr (1),
> although it can be displayed by
> .BR lsattr (1).
> .PP
> -The 'Z' attribute is used by the experimental compression patches to
> +The `Z' attribute is used by the experimental compression patches to
> indicate a compressed file is dirty. It may not be set or reset using
> .BR chattr (1),
> although it can be displayed by
> @@ -179,7 +194,7 @@ although it can be displayed by
> was written by Remy Card <[email protected]>. It is currently being
> maintained by Theodore Ts'o <[email protected]>.
> .SH BUGS AND LIMITATIONS
> -The `c', 's', and `u' attributes are not honored
> +The `c', `s', and `u' attributes are not honored
> by the ext2, ext3, and ext4 filesystems as implemented in the current
> mainline Linux kernels.
> .PP
> @@ -191,4 +206,7 @@ The `D' option is only useful on Linux kernel 2.5.19 and later.
> is part of the e2fsprogs package and is available from
> http://e2fsprogs.sourceforge.net.
> .SH SEE ALSO
> -.BR lsattr (1)
> +.BR lsattr (1),
> +.BR btrfs (5),
> +.BR ext4 (5),
> +.BR xfs (5).
> diff --git a/misc/chattr.c b/misc/chattr.c
> index d5a6a61..f130108 100644
> --- a/misc/chattr.c
> +++ b/misc/chattr.c
> @@ -83,7 +83,7 @@ static unsigned long sf;
> static void usage(void)
> {
> fprintf(stderr,
> - _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
> + _("Usage: %s [-RVf] [-+=aAcCdDeijsStTu] [-v version] files...\n"),
> program_name);
> exit(1);
> }
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2014-06-20 15:00:37

by Eric Sandeen

[permalink] [raw]
Subject: [PATCH 2/2 V2] e2fsprogs: revise and extend chattr(1) and chattr usage()

The chattr(1) manpage and chattr usage() output were missing some flags.

Add those, and make some other minor cosmetic fixes.

(I've left out the 'B' (EXT2_COMPRBLK_FL) flag, because
it's not actually used anywhere, and I can't figure out
how it differs from 'c' (EXT2_COMPR_FL))

Also, because the matrix of filesystems & flags is quite large,
refer to filesystem-specific manpages for detailed discussion
of flags supported by those filesystems, rather than trying to
cover it all in this manpage. I'll send those manpage
updates to the appropriate lists a bit later.

Signed-off-by: Eric Sandeen <[email protected]>
---

V2: Make the single-quotes non-backticky; get consistent in
the other direction.

diff --git a/misc/chattr.1.in b/misc/chattr.1.in
index ce426e8..fd3b39b 100644
--- a/misc/chattr.1.in
+++ b/misc/chattr.1.in
@@ -21,11 +21,11 @@ changes the file attributes on a Linux file system.
.PP
The format of a symbolic mode is +-=[aAcCdDeijsStTu].
.PP
-The operator `+' causes the selected attributes to be added to the
-existing attributes of the files; `-' causes them to be removed; and
-`=' causes them to be the only attributes that the files have.
+The operator '+' causes the selected attributes to be added to the
+existing attributes of the files; '-' causes them to be removed; and
+'=' causes them to be the only attributes that the files have.
.PP
-The letters `aAcCdDeijsStTu' select the new attributes for the files:
+The letters 'aAcCdDeijsStTu' select the new attributes for the files:
append only (a),
no atime updates (A),
compressed (c),
@@ -47,8 +47,17 @@ but not modified by chattr:
compression error (E),
huge file (h),
indexed directory (I),
+inline data (N),
compression raw access (X),
and compressed dirty file (Z).
+.PP
+Not all flags are supported or utilized by all filesystems; refer to
+filesystem-specific man pages such as
+.BR btrfs (5),
+.BR ext4 (5),
+and
+.BR xfs (5)
+for more filesystem-specific details.
.SH OPTIONS
.TP
.B \-R
@@ -63,7 +72,7 @@ Suppress most error messages.
.BI \-v " version"
Set the file's version/generation number.
.SH ATTRIBUTES
-A file with the `a' attribute set can only be open in append mode for writing.
+A file with the 'a' attribute set can only be open in append mode for writing.
Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
capability can set or clear this attribute.
.PP
@@ -71,7 +80,7 @@ When a file with the 'A' attribute set is accessed, its atime record is
not modified. This avoids a certain amount of disk I/O for laptop
systems.
.PP
-A file with the `c' attribute set is automatically compressed on the disk
+A file with the 'c' attribute set is automatically compressed on the disk
by the kernel. A read from this file returns uncompressed data. A write to
this file compresses data before storing them on the disk. Note: please
make sure to read the bugs and limitations section at the end of this
@@ -86,13 +95,13 @@ be fully stable. If the 'C' flag is set on a directory, it will have no
effect on the directory, but new files created in that directory will
the No_COW attribute.)
.PP
-A file with the `d' attribute set is not candidate for backup when the
+A file with the 'd' attribute set is not candidate for backup when the
.BR dump (8)
program is run.
.PP
-When a directory with the `D' attribute set is modified,
+When a directory with the 'D' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
-the `dirsync' mount option applied to a subset of the files.
+the 'dirsync' mount option applied to a subset of the files.
.PP
The 'e' attribute indicates that the file is using extents for mapping
the blocks on disk. It may not be removed using
@@ -112,7 +121,7 @@ is (or at one time was) larger than 2TB. It may not be set or reset using
although it can be displayed by
.BR lsattr (1).
.PP
-A file with the `i' attribute cannot be modified: it cannot be deleted or
+A file with the 'i' attribute cannot be modified: it cannot be deleted or
renamed, no link can be created to this file and no data can be written
to the file. Only the superuser or a process possessing the
CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
@@ -123,7 +132,7 @@ is being indexed using hashed trees. It may not be set or reset using
although it can be displayed by
.BR lsattr (1).
.PP
-A file with the `j' attribute has all of its data written to the ext3
+A file with the 'j' attribute has all of its data written to the ext3
or ext4 journal before being written to the file itself, if the filesystem
is mounted with the "data=ordered" or "data=writeback" options. When the
filesystem is mounted with the "data=journal" option all file data
@@ -131,13 +140,19 @@ is already journalled and this attribute has no effect. Only
the superuser or a process possessing the CAP_SYS_RESOURCE
capability can set or clear this attribute.
.PP
-When a file with the `s' attribute set is deleted, its blocks are zeroed
+A file with the 'N' attribute set indicates that the file has data
+stored inline, within the inode itself. It may not be set or reset using
+.BR chattr (1),
+although it can be displayed by
+.BR lsattr (1).
+.PP
+When a file with the 's' attribute set is deleted, its blocks are zeroed
and written back to the disk. Note: please make sure to read the bugs
and limitations section at the end of this document.
.PP
-When a file with the `S' attribute set is modified,
+When a file with the 'S' attribute set is modified,
the changes are written synchronously on the disk; this is equivalent to
-the `sync' mount option applied to a subset of the files.
+the 'sync' mount option applied to a subset of the files.
.PP
A file with the 't' attribute will not have a partial block fragment at
the end of the file merged with other files (for those filesystems which
@@ -156,13 +171,13 @@ and /home/mary are placed into separate block groups. For directories
where this attribute is not set, the Orlov block allocator will try to
group subdirectories closer together where possible.
.PP
-When a file with the `u' attribute set is deleted, its contents are
+When a file with the 'u' attribute set is deleted, its contents are
saved. This allows the user to ask for its undeletion. Note: please
make sure to read the bugs and limitations section at the end of this
document.
.PP
The 'X' attribute is used by the experimental compression patches to
-indicate that a raw contents of a compressed file can be accessed
+indicate that the raw contents of a compressed file can be accessed
directly. It currently may not be set or reset using
.BR chattr (1),
although it can be displayed by
@@ -179,16 +194,19 @@ although it can be displayed by
was written by Remy Card <[email protected]>. It is currently being
maintained by Theodore Ts'o <[email protected]>.
.SH BUGS AND LIMITATIONS
-The `c', 's', and `u' attributes are not honored
+The 'c', 's', and 'u' attributes are not honored
by the ext2, ext3, and ext4 filesystems as implemented in the current
mainline Linux kernels.
.PP
-The `j' option is only useful if the filesystem is mounted as ext3 or ext4.
+The 'j' option is only useful if the filesystem is mounted as ext3 or ext4.
.PP
-The `D' option is only useful on Linux kernel 2.5.19 and later.
+The 'D' option is only useful on Linux kernel 2.5.19 and later.
.SH AVAILABILITY
.B chattr
is part of the e2fsprogs package and is available from
http://e2fsprogs.sourceforge.net.
.SH SEE ALSO
-.BR lsattr (1)
+.BR lsattr (1),
+.BR btrfs (5),
+.BR ext4 (5),
+.BR xfs (5).
diff --git a/misc/chattr.c b/misc/chattr.c
index d5a6a61..f130108 100644
--- a/misc/chattr.c
+++ b/misc/chattr.c
@@ -83,7 +83,7 @@ static unsigned long sf;
static void usage(void)
{
fprintf(stderr,
- _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
+ _("Usage: %s [-RVf] [-+=aAcCdDeijsStTu] [-v version] files...\n"),
program_name);
exit(1);
}


2014-06-20 18:44:43

by Andreas Dilger

[permalink] [raw]
Subject: Re: [PATCH 2/2 V2] e2fsprogs: revise and extend chattr(1) and chattr usage()

On Jun 20, 2014, at 8:34 AM, Eric Sandeen <[email protected]> wrote:
> The chattr(1) manpage and chattr usage() output were missing some flags.
>
> Add those, and make some other minor cosmetic fixes.
>
> (I've left out the 'B' (EXT2_COMPRBLK_FL) flag, because
> it's not actually used anywhere, and I can't figure out
> how it differs from 'c' (EXT2_COMPR_FL))
>
> Also, because the matrix of filesystems & flags is quite large,
> refer to filesystem-specific manpages for detailed discussion
> of flags supported by those filesystems, rather than trying to
> cover it all in this manpage. I'll send those manpage
> updates to the appropriate lists a bit later.
>
> Signed-off-by: Eric Sandeen <[email protected]>

Reviewed-by: Andreas Dilger <[email protected]>

> ---
>
> V2: Make the single-quotes non-backticky; get consistent in
> the other direction.
>
> diff --git a/misc/chattr.1.in b/misc/chattr.1.in
> index ce426e8..fd3b39b 100644
> --- a/misc/chattr.1.in
> +++ b/misc/chattr.1.in
> @@ -21,11 +21,11 @@ changes the file attributes on a Linux file system.
> .PP
> The format of a symbolic mode is +-=[aAcCdDeijsStTu].
> .PP
> -The operator `+' causes the selected attributes to be added to the
> -existing attributes of the files; `-' causes them to be removed; and
> -`=' causes them to be the only attributes that the files have.
> +The operator '+' causes the selected attributes to be added to the
> +existing attributes of the files; '-' causes them to be removed; and
> +'=' causes them to be the only attributes that the files have.
> .PP
> -The letters `aAcCdDeijsStTu' select the new attributes for the files:
> +The letters 'aAcCdDeijsStTu' select the new attributes for the files:
> append only (a),
> no atime updates (A),
> compressed (c),
> @@ -47,8 +47,17 @@ but not modified by chattr:
> compression error (E),
> huge file (h),
> indexed directory (I),
> +inline data (N),
> compression raw access (X),
> and compressed dirty file (Z).
> +.PP
> +Not all flags are supported or utilized by all filesystems; refer to
> +filesystem-specific man pages such as
> +.BR btrfs (5),
> +.BR ext4 (5),
> +and
> +.BR xfs (5)
> +for more filesystem-specific details.
> .SH OPTIONS
> .TP
> .B \-R
> @@ -63,7 +72,7 @@ Suppress most error messages.
> .BI \-v " version"
> Set the file's version/generation number.
> .SH ATTRIBUTES
> -A file with the `a' attribute set can only be open in append mode for writing.
> +A file with the 'a' attribute set can only be open in append mode for writing.
> Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
> capability can set or clear this attribute.
> .PP
> @@ -71,7 +80,7 @@ When a file with the 'A' attribute set is accessed, its atime record is
> not modified. This avoids a certain amount of disk I/O for laptop
> systems.
> .PP
> -A file with the `c' attribute set is automatically compressed on the disk
> +A file with the 'c' attribute set is automatically compressed on the disk
> by the kernel. A read from this file returns uncompressed data. A write to
> this file compresses data before storing them on the disk. Note: please
> make sure to read the bugs and limitations section at the end of this
> @@ -86,13 +95,13 @@ be fully stable. If the 'C' flag is set on a directory, it will have no
> effect on the directory, but new files created in that directory will
> the No_COW attribute.)
> .PP
> -A file with the `d' attribute set is not candidate for backup when the
> +A file with the 'd' attribute set is not candidate for backup when the
> .BR dump (8)
> program is run.
> .PP
> -When a directory with the `D' attribute set is modified,
> +When a directory with the 'D' attribute set is modified,
> the changes are written synchronously on the disk; this is equivalent to
> -the `dirsync' mount option applied to a subset of the files.
> +the 'dirsync' mount option applied to a subset of the files.
> .PP
> The 'e' attribute indicates that the file is using extents for mapping
> the blocks on disk. It may not be removed using
> @@ -112,7 +121,7 @@ is (or at one time was) larger than 2TB. It may not be set or reset using
> although it can be displayed by
> .BR lsattr (1).
> .PP
> -A file with the `i' attribute cannot be modified: it cannot be deleted or
> +A file with the 'i' attribute cannot be modified: it cannot be deleted or
> renamed, no link can be created to this file and no data can be written
> to the file. Only the superuser or a process possessing the
> CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
> @@ -123,7 +132,7 @@ is being indexed using hashed trees. It may not be set or reset using
> although it can be displayed by
> .BR lsattr (1).
> .PP
> -A file with the `j' attribute has all of its data written to the ext3
> +A file with the 'j' attribute has all of its data written to the ext3
> or ext4 journal before being written to the file itself, if the filesystem
> is mounted with the "data=ordered" or "data=writeback" options. When the
> filesystem is mounted with the "data=journal" option all file data
> @@ -131,13 +140,19 @@ is already journalled and this attribute has no effect. Only
> the superuser or a process possessing the CAP_SYS_RESOURCE
> capability can set or clear this attribute.
> .PP
> -When a file with the `s' attribute set is deleted, its blocks are zeroed
> +A file with the 'N' attribute set indicates that the file has data
> +stored inline, within the inode itself. It may not be set or reset using
> +.BR chattr (1),
> +although it can be displayed by
> +.BR lsattr (1).
> +.PP
> +When a file with the 's' attribute set is deleted, its blocks are zeroed
> and written back to the disk. Note: please make sure to read the bugs
> and limitations section at the end of this document.
> .PP
> -When a file with the `S' attribute set is modified,
> +When a file with the 'S' attribute set is modified,
> the changes are written synchronously on the disk; this is equivalent to
> -the `sync' mount option applied to a subset of the files.
> +the 'sync' mount option applied to a subset of the files.
> .PP
> A file with the 't' attribute will not have a partial block fragment at
> the end of the file merged with other files (for those filesystems which
> @@ -156,13 +171,13 @@ and /home/mary are placed into separate block groups. For directories
> where this attribute is not set, the Orlov block allocator will try to
> group subdirectories closer together where possible.
> .PP
> -When a file with the `u' attribute set is deleted, its contents are
> +When a file with the 'u' attribute set is deleted, its contents are
> saved. This allows the user to ask for its undeletion. Note: please
> make sure to read the bugs and limitations section at the end of this
> document.
> .PP
> The 'X' attribute is used by the experimental compression patches to
> -indicate that a raw contents of a compressed file can be accessed
> +indicate that the raw contents of a compressed file can be accessed
> directly. It currently may not be set or reset using
> .BR chattr (1),
> although it can be displayed by
> @@ -179,16 +194,19 @@ although it can be displayed by
> was written by Remy Card <[email protected]>. It is currently being
> maintained by Theodore Ts'o <[email protected]>.
> .SH BUGS AND LIMITATIONS
> -The `c', 's', and `u' attributes are not honored
> +The 'c', 's', and 'u' attributes are not honored
> by the ext2, ext3, and ext4 filesystems as implemented in the current
> mainline Linux kernels.
> .PP
> -The `j' option is only useful if the filesystem is mounted as ext3 or ext4.
> +The 'j' option is only useful if the filesystem is mounted as ext3 or ext4.
> .PP
> -The `D' option is only useful on Linux kernel 2.5.19 and later.
> +The 'D' option is only useful on Linux kernel 2.5.19 and later.
> .SH AVAILABILITY
> .B chattr
> is part of the e2fsprogs package and is available from
> http://e2fsprogs.sourceforge.net.
> .SH SEE ALSO
> -.BR lsattr (1)
> +.BR lsattr (1),
> +.BR btrfs (5),
> +.BR ext4 (5),
> +.BR xfs (5).
> diff --git a/misc/chattr.c b/misc/chattr.c
> index d5a6a61..f130108 100644
> --- a/misc/chattr.c
> +++ b/misc/chattr.c
> @@ -83,7 +83,7 @@ static unsigned long sf;
> static void usage(void)
> {
> fprintf(stderr,
> - _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
> + _("Usage: %s [-RVf] [-+=aAcCdDeijsStTu] [-v version] files...\n"),
> program_name);
> exit(1);
> }
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html


Cheers, Andreas






Attachments:
signature.asc (833.00 B)
Message signed with OpenPGP using GPGMail

2014-06-20 18:45:32

by Andreas Dilger

[permalink] [raw]
Subject: Re: [PATCH 1/2 V2] e2fsprogs: reorder flags in chattr(1)

On Jun 19, 2014, at 5:17 PM, Eric Sandeen <[email protected]> wrote:

> The flags described in chattr usage() and the chattr(1) manpage
> were in semi-random order, which makes it hard to ascertain
> which flags might be missing or undocumented, and to locate
> flags within the manpage.
>
> Re-order the list of flags in alphanumeric order, and do
> the same for the flag descriptions in the body of the manpage.
>
> There should be no content changes here, just reordering
> for consistency.
>
> Signed-off-by: Eric Sandeen <[email protected]>

Reviewed-by: Andreas Dilger <[email protected]>

> ---
>
> V2: remove duplicate line in usage()!
> (why do I only spot these things immediately after I hit send?)
>
> diff --git a/misc/chattr.1.in b/misc/chattr.1.in
> index 2a3640c..ce426e8 100644
> --- a/misc/chattr.1.in
> +++ b/misc/chattr.1.in
> @@ -19,24 +19,36 @@ chattr \- change file attributes on a Linux file system
> .B chattr
> changes the file attributes on a Linux file system.
> .PP
> -The format of a symbolic mode is +-=[acdeijstuACDST].
> +The format of a symbolic mode is +-=[aAcCdDeijsStTu].
> .PP
> The operator `+' causes the selected attributes to be added to the
> existing attributes of the files; `-' causes them to be removed; and
> `=' causes them to be the only attributes that the files have.
> .PP
> -The letters `acdeijstuACDST' select the new attributes for the files:
> -append only (a), compressed (c), no dump (d), extent format (e), immutable (i),
> -data journalling (j), secure deletion (s), no tail-merging (t),
> -undeletable (u), no atime updates (A), no copy on write (C),
> -synchronous directory updates (D), synchronous updates (S),
> -and top of directory hierarchy (T).
> +The letters `aAcCdDeijsStTu' select the new attributes for the files:
> +append only (a),
> +no atime updates (A),
> +compressed (c),
> +no copy on write (C),
> +no dump (d),
> +synchronous directory updates (D),
> +extent format (e),
> +immutable (i),
> +data journalling (j),
> +secure deletion (s),
> +synchronous updates (S),
> +no tail-merging (t),
> +top of directory hierarchy (T),
> +and undeletable (u).
> .PP
> The following attributes are read-only, and may be listed by
> .BR lsattr (1)
> -but not modified by chattr: huge file (h), compression error (E),
> -indexed directory (I), compression raw access (X), and compressed dirty
> -file (Z).
> +but not modified by chattr:
> +compression error (E),
> +huge file (h),
> +indexed directory (I),
> +compression raw access (X),
> +and compressed dirty file (Z).
> .SH OPTIONS
> .TP
> .B \-R
> @@ -51,14 +63,14 @@ Suppress most error messages.
> .BI \-v " version"
> Set the file's version/generation number.
> .SH ATTRIBUTES
> -When a file with the 'A' attribute set is accessed, its atime record is
> -not modified. This avoids a certain amount of disk I/O for laptop
> -systems.
> -.PP
> A file with the `a' attribute set can only be open in append mode for writing.
> Only the superuser or a process possessing the CAP_LINUX_IMMUTABLE
> capability can set or clear this attribute.
> .PP
> +When a file with the 'A' attribute set is accessed, its atime record is
> +not modified. This avoids a certain amount of disk I/O for laptop
> +systems.
> +.PP
> A file with the `c' attribute set is automatically compressed on the disk
> by the kernel. A read from this file returns uncompressed data. A write to
> this file compresses data before storing them on the disk. Note: please
> @@ -74,27 +86,21 @@ be fully stable. If the 'C' flag is set on a directory, it will have no
> effect on the directory, but new files created in that directory will
> the No_COW attribute.)
> .PP
> -When a directory with the `D' attribute set is modified,
> -the changes are written synchronously on the disk; this is equivalent to
> -the `dirsync' mount option applied to a subset of the files.
> -.PP
> A file with the `d' attribute set is not candidate for backup when the
> .BR dump (8)
> program is run.
> .PP
> -The 'E' attribute is used by the experimental compression patches to
> -indicate that a compressed file has a compression error. It may not be
> -set or reset using
> -.BR chattr (1),
> -although it can be displayed by
> -.BR lsattr (1).
> +When a directory with the `D' attribute set is modified,
> +the changes are written synchronously on the disk; this is equivalent to
> +the `dirsync' mount option applied to a subset of the files.
> .PP
> The 'e' attribute indicates that the file is using extents for mapping
> the blocks on disk. It may not be removed using
> .BR chattr (1).
> .PP
> -The 'I' attribute is used by the htree code to indicate that a directory
> -is being indexed using hashed trees. It may not be set or reset using
> +The 'E' attribute is used by the experimental compression patches to
> +indicate that a compressed file has a compression error. It may not be
> +set or reset using
> .BR chattr (1),
> although it can be displayed by
> .BR lsattr (1).
> @@ -111,6 +117,12 @@ renamed, no link can be created to this file and no data can be written
> to the file. Only the superuser or a process possessing the
> CAP_LINUX_IMMUTABLE capability can set or clear this attribute.
> .PP
> +The 'I' attribute is used by the htree code to indicate that a directory
> +is being indexed using hashed trees. It may not be set or reset using
> +.BR chattr (1),
> +although it can be displayed by
> +.BR lsattr (1).
> +.PP
> A file with the `j' attribute has all of its data written to the ext3
> or ext4 journal before being written to the file itself, if the filesystem
> is mounted with the "data=ordered" or "data=writeback" options. When the
> @@ -127,6 +139,13 @@ When a file with the `S' attribute set is modified,
> the changes are written synchronously on the disk; this is equivalent to
> the `sync' mount option applied to a subset of the files.
> .PP
> +A file with the 't' attribute will not have a partial block fragment at
> +the end of the file merged with other files (for those filesystems which
> +support tail-merging). This is necessary for applications such as LILO
> +which read the filesystem directly, and which don't understand tail-merged
> +files. Note: As of this writing, the ext2 or ext3 filesystems do not
> +(yet, except in very experimental patches) support tail-merging.
> +.PP
> A directory with the 'T' attribute will be deemed to be the top of
> directory hierarchies for the purposes of the Orlov block allocator.
> This is a hint to the block allocator used by ext3 and ext4 that the
> @@ -137,13 +156,6 @@ and /home/mary are placed into separate block groups. For directories
> where this attribute is not set, the Orlov block allocator will try to
> group subdirectories closer together where possible.
> .PP
> -A file with the 't' attribute will not have a partial block fragment at
> -the end of the file merged with other files (for those filesystems which
> -support tail-merging). This is necessary for applications such as LILO
> -which read the filesystem directly, and which don't understand tail-merged
> -files. Note: As of this writing, the ext2 or ext3 filesystems do not
> -(yet, except in very experimental patches) support tail-merging.
> -.PP
> When a file with the `u' attribute set is deleted, its contents are
> saved. This allows the user to ask for its undeletion. Note: please
> make sure to read the bugs and limitations section at the end of this
> diff --git a/misc/chattr.c b/misc/chattr.c
> index 39a6016..d5a6a61 100644
> --- a/misc/chattr.c
> +++ b/misc/chattr.c
> @@ -83,7 +83,7 @@ static unsigned long sf;
> static void usage(void)
> {
> fprintf(stderr,
> - _("Usage: %s [-RVf] [-+=AaCcDdeijsSu] [-v version] files...\n"),
> + _("Usage: %s [-RVf] [-+=aAcCdDeijsSu] [-v version] files...\n"),
> program_name);
> exit(1);
> }
>
> --
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> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html


Cheers, Andreas






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2014-07-05 03:05:16

by Theodore Ts'o

[permalink] [raw]
Subject: Re: [PATCH 1/2 V2] e2fsprogs: reorder flags in chattr(1)

On Thu, Jun 19, 2014 at 06:17:49PM -0500, Eric Sandeen wrote:
> The flags described in chattr usage() and the chattr(1) manpage
> were in semi-random order, which makes it hard to ascertain
> which flags might be missing or undocumented, and to locate
> flags within the manpage.
>
> Re-order the list of flags in alphanumeric order, and do
> the same for the flag descriptions in the body of the manpage.
>
> There should be no content changes here, just reordering
> for consistency.
>
> Signed-off-by: Eric Sandeen <[email protected]>

Applied, thanks.

- Ted

2014-07-05 03:05:28

by Theodore Ts'o

[permalink] [raw]
Subject: Re: [PATCH 2/2 V2] e2fsprogs: revise and extend chattr(1) and chattr usage()

On Fri, Jun 20, 2014 at 09:34:33AM -0500, Eric Sandeen wrote:
> The chattr(1) manpage and chattr usage() output were missing some flags.
>
> Add those, and make some other minor cosmetic fixes.
>
> (I've left out the 'B' (EXT2_COMPRBLK_FL) flag, because
> it's not actually used anywhere, and I can't figure out
> how it differs from 'c' (EXT2_COMPR_FL))
>
> Also, because the matrix of filesystems & flags is quite large,
> refer to filesystem-specific manpages for detailed discussion
> of flags supported by those filesystems, rather than trying to
> cover it all in this manpage. I'll send those manpage
> updates to the appropriate lists a bit later.
>
> Signed-off-by: Eric Sandeen <[email protected]>

Applied, thanks.

- Ted