[PATCH v2] fs/ext*,f2fs,jffs2,reiserfs: give comments for acl size and count calculation
Chen Gang
gang.chen at asianux.com
Thu Jan 3 22:04:28 EST 2013
give comments (by Theodore Ts'o)
ACL_USER_OBJ ACL_USER*[1] ACL_GROUP_OBJ ACL_GROUP*[1] ACL_MASK[2] ACL_OTHER
[1] Where * is the regexp sense of "0 or more times"
[2] Only if there is at least one ACL_USER or ACL_GROUP tag;
otherwise skip ACL_MASK.
give comments (by Jan Kara)
posix_acl_valid() makes sure that if there are <= 4 ACL entries, then
all of them are short. Otherwise exactly 4 entries are short ones and
other have full length. See comment before that function for exact ACL
format.
use macro instead of hard code number (by Chen Gang)
Signed-off-by: Theodore Ts'o <tytso at mit.edu>
Signed-off-by: Jan Kara <jack at suse.cz>
Signed-off-by: Chen Gang <gang.chen at asianux.com>
---
fs/ext2/acl.h | 10 +++++-----
fs/ext3/acl.h | 10 +++++-----
fs/ext4/acl.h | 10 +++++-----
fs/f2fs/acl.c | 12 +++++++-----
fs/jffs2/acl.c | 15 +++++++++------
fs/posix_acl.c | 8 ++++++++
fs/reiserfs/acl.h | 10 +++++-----
include/linux/posix_acl.h | 8 ++++++++
8 files changed, 52 insertions(+), 31 deletions(-)
diff --git a/fs/ext2/acl.h b/fs/ext2/acl.h
index 503bfb0..9af79d0 100644
--- a/fs/ext2/acl.h
+++ b/fs/ext2/acl.h
@@ -25,13 +25,13 @@ typedef struct {
static inline size_t ext2_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(ext2_acl_header) +
count * sizeof(ext2_acl_entry_short);
} else {
return sizeof(ext2_acl_header) +
- 4 * sizeof(ext2_acl_entry_short) +
- (count - 4) * sizeof(ext2_acl_entry);
+ ACL_MAX_SHORT_ENTRY * sizeof(ext2_acl_entry_short) +
+ (count - ACL_MAX_SHORT_ENTRY) * sizeof(ext2_acl_entry);
}
}
@@ -39,7 +39,7 @@ static inline int ext2_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(ext2_acl_header);
- s = size - 4 * sizeof(ext2_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY * sizeof(ext2_acl_entry_short);
if (s < 0) {
if (size % sizeof(ext2_acl_entry_short))
return -1;
@@ -47,7 +47,7 @@ static inline int ext2_acl_count(size_t size)
} else {
if (s % sizeof(ext2_acl_entry))
return -1;
- return s / sizeof(ext2_acl_entry) + 4;
+ return s / sizeof(ext2_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/fs/ext3/acl.h b/fs/ext3/acl.h
index dbc921e..b1cf2c0 100644
--- a/fs/ext3/acl.h
+++ b/fs/ext3/acl.h
@@ -25,13 +25,13 @@ typedef struct {
static inline size_t ext3_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(ext3_acl_header) +
count * sizeof(ext3_acl_entry_short);
} else {
return sizeof(ext3_acl_header) +
- 4 * sizeof(ext3_acl_entry_short) +
- (count - 4) * sizeof(ext3_acl_entry);
+ ACL_MAX_SHORT_ENTRY * sizeof(ext3_acl_entry_short) +
+ (count - ACL_MAX_SHORT_ENTRY) * sizeof(ext3_acl_entry);
}
}
@@ -39,7 +39,7 @@ static inline int ext3_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(ext3_acl_header);
- s = size - 4 * sizeof(ext3_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY * sizeof(ext3_acl_entry_short);
if (s < 0) {
if (size % sizeof(ext3_acl_entry_short))
return -1;
@@ -47,7 +47,7 @@ static inline int ext3_acl_count(size_t size)
} else {
if (s % sizeof(ext3_acl_entry))
return -1;
- return s / sizeof(ext3_acl_entry) + 4;
+ return s / sizeof(ext3_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
index 18cb39e..66d1fa3 100644
--- a/fs/ext4/acl.h
+++ b/fs/ext4/acl.h
@@ -25,13 +25,13 @@ typedef struct {
static inline size_t ext4_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(ext4_acl_header) +
count * sizeof(ext4_acl_entry_short);
} else {
return sizeof(ext4_acl_header) +
- 4 * sizeof(ext4_acl_entry_short) +
- (count - 4) * sizeof(ext4_acl_entry);
+ ACL_MAX_SHORT_ENTRY * sizeof(ext4_acl_entry_short) +
+ (count - ACL_MAX_SHORT_ENTRY) * sizeof(ext4_acl_entry);
}
}
@@ -39,7 +39,7 @@ static inline int ext4_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(ext4_acl_header);
- s = size - 4 * sizeof(ext4_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY * sizeof(ext4_acl_entry_short);
if (s < 0) {
if (size % sizeof(ext4_acl_entry_short))
return -1;
@@ -47,7 +47,7 @@ static inline int ext4_acl_count(size_t size)
} else {
if (s % sizeof(ext4_acl_entry))
return -1;
- return s / sizeof(ext4_acl_entry) + 4;
+ return s / sizeof(ext4_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c
index fed74d1..42e0070 100644
--- a/fs/f2fs/acl.c
+++ b/fs/f2fs/acl.c
@@ -22,13 +22,15 @@
static inline size_t f2fs_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(struct f2fs_acl_header) +
count * sizeof(struct f2fs_acl_entry_short);
} else {
return sizeof(struct f2fs_acl_header) +
- 4 * sizeof(struct f2fs_acl_entry_short) +
- (count - 4) * sizeof(struct f2fs_acl_entry);
+ ACL_MAX_SHORT_ENTRY
+ * sizeof(struct f2fs_acl_entry_short) +
+ (count - ACL_MAX_SHORT_ENTRY)
+ * sizeof(struct f2fs_acl_entry);
}
}
@@ -36,7 +38,7 @@ static inline int f2fs_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(struct f2fs_acl_header);
- s = size - 4 * sizeof(struct f2fs_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY * sizeof(struct f2fs_acl_entry_short);
if (s < 0) {
if (size % sizeof(struct f2fs_acl_entry_short))
return -1;
@@ -44,7 +46,7 @@ static inline int f2fs_acl_count(size_t size)
} else {
if (s % sizeof(struct f2fs_acl_entry))
return -1;
- return s / sizeof(struct f2fs_acl_entry) + 4;
+ return s / sizeof(struct f2fs_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c
index 223283c..48ef4b8 100644
--- a/fs/jffs2/acl.c
+++ b/fs/jffs2/acl.c
@@ -25,13 +25,15 @@
static size_t jffs2_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(struct jffs2_acl_header)
+ count * sizeof(struct jffs2_acl_entry_short);
} else {
return sizeof(struct jffs2_acl_header)
- + 4 * sizeof(struct jffs2_acl_entry_short)
- + (count - 4) * sizeof(struct jffs2_acl_entry);
+ + ACL_MAX_SHORT_ENTRY
+ * sizeof(struct jffs2_acl_entry_short)
+ + (count - ACL_MAX_SHORT_ENTRY)
+ * sizeof(struct jffs2_acl_entry);
}
}
@@ -40,15 +42,16 @@ static int jffs2_acl_count(size_t size)
size_t s;
size -= sizeof(struct jffs2_acl_header);
- if (size < 4 * sizeof(struct jffs2_acl_entry_short)) {
+ if (size < ACL_MAX_SHORT_ENTRY * sizeof(struct jffs2_acl_entry_short)) {
if (size % sizeof(struct jffs2_acl_entry_short))
return -1;
return size / sizeof(struct jffs2_acl_entry_short);
} else {
- s = size - 4 * sizeof(struct jffs2_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY
+ * sizeof(struct jffs2_acl_entry_short);
if (s % sizeof(struct jffs2_acl_entry))
return -1;
- return s / sizeof(struct jffs2_acl_entry) + 4;
+ return s / sizeof(struct jffs2_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 8bd2135..8cfdebe 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -72,6 +72,14 @@ posix_acl_clone(const struct posix_acl *acl, gfp_t flags)
/*
* Check if an acl is valid. Returns 0 if it is, or -E... otherwise.
+ *
+ * make sure ACL format is the following:
+ *
+ * ACL_USER_OBJ ACL_USER*[1] ACL_GROUP_OBJ ACL_GROUP*[1] ACL_MASK[2] ACL_OTHER
+ *
+ * [1] Where * is the regexp sense of "0 or more times"
+ * [2] Only if there is at least one ACL_USER or ACL_GROUP tag;
+ * otherwise skip ACL_MASK.
*/
int
posix_acl_valid(const struct posix_acl *acl)
diff --git a/fs/reiserfs/acl.h b/fs/reiserfs/acl.h
index f096b80..cb967a3 100644
--- a/fs/reiserfs/acl.h
+++ b/fs/reiserfs/acl.h
@@ -20,13 +20,13 @@ typedef struct {
static inline size_t reiserfs_acl_size(int count)
{
- if (count <= 4) {
+ if (count <= ACL_MAX_SHORT_ENTRY) {
return sizeof(reiserfs_acl_header) +
count * sizeof(reiserfs_acl_entry_short);
} else {
return sizeof(reiserfs_acl_header) +
- 4 * sizeof(reiserfs_acl_entry_short) +
- (count - 4) * sizeof(reiserfs_acl_entry);
+ ACL_MAX_SHORT_ENTRY * sizeof(reiserfs_acl_entry_short) +
+ (count - ACL_MAX_SHORT_ENTRY) * sizeof(reiserfs_acl_entry);
}
}
@@ -34,7 +34,7 @@ static inline int reiserfs_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(reiserfs_acl_header);
- s = size - 4 * sizeof(reiserfs_acl_entry_short);
+ s = size - ACL_MAX_SHORT_ENTRY * sizeof(reiserfs_acl_entry_short);
if (s < 0) {
if (size % sizeof(reiserfs_acl_entry_short))
return -1;
@@ -42,7 +42,7 @@ static inline int reiserfs_acl_count(size_t size)
} else {
if (s % sizeof(reiserfs_acl_entry))
return -1;
- return s / sizeof(reiserfs_acl_entry) + 4;
+ return s / sizeof(reiserfs_acl_entry) + ACL_MAX_SHORT_ENTRY;
}
}
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 7931efe..7a8ee64 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -26,6 +26,14 @@
#define ACL_MASK (0x10)
#define ACL_OTHER (0x20)
+/*
+ * posix_acl_valid() makes sure that if there are <= 4 ACL entries, then
+ * all of them are short. Otherwise exactly 4 entries are short ones and
+ * other have full length. See comment before that function for exact ACL
+ * format.
+ */
+#define ACL_MAX_SHORT_ENTRY (4)
+
/* permissions in the e_perm field */
#define ACL_READ (0x04)
#define ACL_WRITE (0x02)
--
1.7.10.4
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