trivial: document ext3 semantics of 'ro' option a bit better

ext3 has quite unexpected semantics or "ro" and defaults are not what they are documented to be, due to mkfs override. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Jiri Kosina <jkosina@suse.cz>

trivial: document ext3 semantics of 'ro' option a bit better
ext3 has quite unexpected semantics or "ro" and defaults are not what they are documented to be, due to mkfs override. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pavel Machek · Jiri Kosina
1 parent 0d34fb8e93
Showing 1 changed file with 12 additions and 2 deletions Side-by-side Diff
Documentation/filesystems/ext3.txt
@@ -14,6 +14,11 @@
 When mounting an ext3 filesystem, the following option are accepted:
 (*) == default
  
+ro			Mount filesystem read only. Note that ext3 will replay
+			the journal (and thus write to the partition) even when
+			mounted "read only". Mount options "ro,noload" can be
+			used to prevent writes to the filesystem.
+
 journal=update		Update the ext3 file system's journal to the current
 			format.
  
@@ -27,7 +32,9 @@
 			identified through its new major/minor numbers encoded
 			in devnum.
  
-noload			Don't load the journal on mounting.
+noload			Don't load the journal on mounting. Note that this forces
+			mount of inconsistent filesystem, which can lead to
+			various problems.
  
 data=journal		All data are committed into the journal prior to being
 			written into the main file system.
  
@@ -92,9 +99,12 @@
  
 debug			Extra debugging information is sent to syslog.
  
-errors=remount-ro(*)	Remount the filesystem read-only on an error.
+errors=remount-ro	Remount the filesystem read-only on an error.
 errors=continue		Keep going on a filesystem error.
 errors=panic		Panic and halt the machine if an error occurs.
+			(These mount options override the errors behavior
+			specified in the superblock, which can be
+			configured using tune2fs.)
  
 data_err=ignore(*)	Just print an error message if an error occurs
 			in a file data buffer in ordered mode.
...	...	@@ -14,6 +14,11 @@
14	14	When mounting an ext3 filesystem, the following option are accepted:
15	15	(*) == default
16	16
	17	+ro Mount filesystem read only. Note that ext3 will replay
	18	+ the journal (and thus write to the partition) even when
	19	+ mounted "read only". Mount options "ro,noload" can be
	20	+ used to prevent writes to the filesystem.
	21	+
17	22	journal=update Update the ext3 file system's journal to the current
18	23	format.
19	24
...	...	@@ -27,7 +32,9 @@
27	32	identified through its new major/minor numbers encoded
28	33	in devnum.
29	34
30		-noload Don't load the journal on mounting.
	35	+noload Don't load the journal on mounting. Note that this forces
	36	+ mount of inconsistent filesystem, which can lead to
	37	+ various problems.
31	38
32	39	data=journal All data are committed into the journal prior to being
33	40	written into the main file system.
34	41
...	...	@@ -92,9 +99,12 @@
92	99
93	100	debug Extra debugging information is sent to syslog.
94	101
95		-errors=remount-ro(*) Remount the filesystem read-only on an error.
	102	+errors=remount-ro Remount the filesystem read-only on an error.
96	103	errors=continue Keep going on a filesystem error.
97	104	errors=panic Panic and halt the machine if an error occurs.
	105	+ (These mount options override the errors behavior
	106	+ specified in the superblock, which can be
	107	+ configured using tune2fs.)
98	108
99	109	data_err=ignore(*) Just print an error message if an error occurs
100	110	in a file data buffer in ordered mode.