[PATCH 13/17] NTFS: $EA attributes can be both resident non-resident.

Anton Altaparmakov
2005-10-31T14:38:19Z

NTFS: $EA attributes can be both resident non-resident.
Minor tidying.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

---

fs/ntfs/ChangeLog | 1 +
fs/ntfs/aops.c | 5 ++---
fs/ntfs/attrib.c | 2 +-
fs/ntfs/file.c | 14 ++++++++++++++
fs/ntfs/layout.h | 27 +++++++++++++++++----------
5 files changed, 35 insertions(+), 14 deletions(-)

applies-to: 8892cc84dbee2b4387c9f2604a7892b6ef3aab25
7d0ffdb279105d9a87b447758ce4a634496abfd1
diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog
index 03015c7..bc6ec16 100644
--- a/fs/ntfs/ChangeLog
+++ b/fs/ntfs/ChangeLog
@@ -75,6 +75,7 @@ ToDo/Notes:
for highly fragmented files, i.e. ones whose data attribute is split
across multiple extents. When such a case is encountered,
EOPNOTSUPP is returned.
+ - $EA attributes can be both resident non-resident.

2.1.24 - Lots of bug fixes and support more clean journal states.

diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index 8f23c60..1c0a431 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -1391,8 +1391,7 @@ retry_writepage:
if (NInoEncrypted(ni)) {
unlock_page(page);
BUG_ON(ni->type != AT_DATA);
- ntfs_debug("Denying write access to encrypted "
- "file.");
+ ntfs_debug("Denying write access to encrypted file.");
return -EACCES;
}
/* Compressed data streams are handled in compress.c. */
@@ -1508,8 +1507,8 @@ retry_writepage:
/* Zero out of bounds area in the page cache page. */
memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
kunmap_atomic(kaddr, KM_USER0);
- flush_dcache_mft_record_page(ctx->ntfs_ino);
flush_dcache_page(page);
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
/* We are done with the page. */
end_page_writeback(page);
/* Finally, mark the mft record dirty, so it gets written back. */
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c
index 338e471..df2e209 100644
--- a/fs/ntfs/attrib.c
+++ b/fs/ntfs/attrib.c
@@ -1411,7 +1411,7 @@ int ntfs_attr_can_be_non_resident(const
*/
int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type)
{
- if (type == AT_INDEX_ALLOCATION || type == AT_EA)
+ if (type == AT_INDEX_ALLOCATION)
return -EPERM;
return 0;
}
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index cf2a0e2..5fb341a 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -1857,10 +1857,24 @@ static ssize_t ntfs_file_buffered_write(
if (ni->type != AT_INDEX_ALLOCATION) {
/* If file is encrypted, deny access, just like NT4. */
if (NInoEncrypted(ni)) {
+ /*
+ * Reminder for later: Encrypted files are _always_
+ * non-resident so that the content can always be
+ * encrypted.
+ */
ntfs_debug("Denying write access to encrypted file.");
return -EACCES;
}
if (NInoCompressed(ni)) {
+ /* Only unnamed $DATA attribute can be compressed. */
+ BUG_ON(ni->type != AT_DATA);
+ BUG_ON(ni->name_len);
+ /*
+ * Reminder for later: If resident, the data is not
+ * actually compressed. Only on the switch to non-
+ * resident does compression kick in. This is in
+ * contrast to encrypted files (see above).
+ */
ntfs_error(vi->i_sb, "Writing to compressed files is "
"not implemented yet. Sorry.");
return -EOPNOTSUPP;
diff --git a/fs/ntfs/layout.h b/fs/ntfs/layout.h
index 5c248d4..71b25da 100644
--- a/fs/ntfs/layout.h
+++ b/fs/ntfs/layout.h
@@ -1021,10 +1021,17 @@ enum {
FILE_NAME_POSIX = 0x00,
/* This is the largest namespace. It is case sensitive and allows all
Unicode characters except for: '\0' and '/'. Beware that in
- WinNT/2k files which eg have the same name except for their case
- will not be distinguished by the standard utilities and thus a "del
- filename" will delete both "filename" and "fileName" without
- warning. */
+ WinNT/2k/2003 by default files which eg have the same name except
+ for their case will not be distinguished by the standard utilities
+ and thus a "del filename" will delete both "filename" and "fileName"
+ without warning. However if for example Services For Unix (SFU) are
+ installed and the case sensitive option was enabled at installation
+ time, then you can create/access/delete such files.
+ Note that even SFU places restrictions on the filenames beyond the
+ '\0' and '/' and in particular the following set of characters is
+ not allowed: '"', '/', '<', '>', '\'. All other characters,
+ including the ones no allowed in WIN32 namespace are allowed.
+ Tested with SFU 3.5 (this is now free) running on Windows XP. */
FILE_NAME_WIN32 = 0x01,
/* The standard WinNT/2k NTFS long filenames. Case insensitive. All
Unicode chars except: '\0', '"', '*', '/', ':', '<', '>', '?', '\',
@@ -2375,20 +2382,20 @@ typedef u8 EA_FLAGS;
/*
* Attribute: Extended attribute (EA) (0xe0).
*
- * NOTE: Always non-resident. (Is this true?)
+ * NOTE: Can be resident or non-resident.
*
* Like the attribute list and the index buffer list, the EA attribute value is
* a sequence of EA_ATTR variable length records.
- *
- * FIXME: It appears weird that the EA name is not unicode. Is it true?
*/
typedef struct {
le32 next_entry_offset; /* Offset to the next EA_ATTR. */
EA_FLAGS flags; /* Flags describing the EA. */
- u8 ea_name_length; /* Length of the name of the EA in bytes. */
+ u8 ea_name_length; /* Length of the name of the EA in bytes
+ excluding the '\0' byte terminator. */
le16 ea_value_length; /* Byte size of the EA's value. */
- u8 ea_name[0]; /* Name of the EA. */
- u8 ea_value[0]; /* The value of the EA. Immediately follows
+ u8 ea_name[0]; /* Name of the EA. Note this is ASCII, not
+ Unicode and it is zero terminated. */
+ u8 ea_value[0]; /* The value of the EA. Immediately follows
the name. */
} __attribute__ ((__packed__)) EA_ATTR;

---
0.99.9