From: Darrick J. Wong <djwong@xxxxxxxxxx>
In preparation for parent pointers, we added a few new opcodes for
logged extended attribute updates. Document them now.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
.../journaling_log.asciidoc | 54 ++++++++++++++++++--
1 file changed, 48 insertions(+), 6 deletions(-)
diff --git a/design/XFS_Filesystem_Structure/journaling_log.asciidoc b/design/XFS_Filesystem_Structure/journaling_log.asciidoc
index 9d9fa836..6b9d65c3 100644
--- a/design/XFS_Filesystem_Structure/journaling_log.asciidoc
+++ b/design/XFS_Filesystem_Structure/journaling_log.asciidoc
@@ -730,10 +730,18 @@ of file block mapping operation we want.
.Extended attribute update log intent types
[options="header"]
|=====
-| Value | Description
-| +XFS_ATTRI_OP_FLAGS_SET+ | Set a key/value pair.
-| +XFS_ATTRI_OP_FLAGS_REMOVE+ | Remove a key/value pair.
-| +XFS_ATTRI_OP_FLAGS_REPLACE+ | Replace one key/value pair with another.
+| Value | Description
+| +XFS_ATTRI_OP_FLAGS_SET+ | Associate an attribute name with the
+given value, creating an entry for the name if necessary.
+| +XFS_ATTRI_OP_FLAGS_REMOVE+ | Remove an attribute name and any
+value associated with it.
+| +XFS_ATTRI_OP_FLAGS_REPLACE+ | Remove any value associated with an
+attribute name, then associate the name with the given value.
+| +XFS_ATTRI_OP_FLAGS_PPTR_SET+ | Add a parent pointer associating a directory entry name with a file handle to the parent directory. The (name, handle) tuple must not exist in the attribute structure.
+| +XFS_ATTRI_OP_FLAGS_PPTR_REMOVE+ | Remove a parent pointer from the attribute structure. The (name, handle) tuple must already exist.
+| +XFS_ATTRI_OP_FLAGS_PPTR_REPLACE+ | Remove a specific (name, handle) tuple from
+the attribute structure, then add a new (name, handle) tuple to the attribute structure.
+The two names and handles need not be the same.
|=====
The ``extended attribute update intent'' operation comes first; it tells the
@@ -747,11 +755,17 @@ through the complex update will be replayed fully during log recovery.
struct xfs_attri_log_format {
uint16_t alfi_type;
uint16_t alfi_size;
- uint32_t __pad;
+ uint32_t alfi_igen;
uint64_t alfi_id;
uint64_t alfi_ino;
uint32_t alfi_op_flags;
- uint32_t alfi_name_len;
+ union {
+ uint32_t alfi_name_len;
+ struct {
+ uint16_t alfi_old_name_len;
+ uint16_t alfi_new_name_len;
+ };
+ };
uint32_t alfi_value_len;
uint32_t alfi_attr_filter;
};
@@ -764,6 +778,9 @@ order, not big-endian like the rest of XFS.
*alfi_size*::
Size of this log item. Should be 1.
+*alfi_igen*::
+Generation number of the file being updated.
+
*alfi_id*::
A 64-bit number that binds the corresponding ATTRD log item to this ATTRI log
item.
@@ -778,6 +795,13 @@ The operation being performed. The lower byte must be one of the
*alfi_name_len*::
Length of the name of the extended attribute. This must not be zero.
The attribute name itself is captured in the next log item.
+This field is not defined for the PPTR_REPLACE opcode.
+
+*alfi_old_name_len*::
+For PPTR_REPLACE, this is the length of the old name.
+
+*alfi_new_name_len*::
+For PPTR_REPLACE, this is the length of the new name.
*alfi_value_len*::
Length of the value of the extended attribute. This must be zero for remove
@@ -789,6 +813,24 @@ name.
Attribute namespace filter flags. This must be one of +ATTR_ROOT+,
+ATTR_SECURE+, or +ATTR_INCOMPLETE+.
+For a SET or REPLACE opcode, there should be two regions after the ATTRI intent
+item. The first region contains the attribute name and the second contains the
+attribute value.
+
+For a REMOVE opcode, there should only be one region after the ATTRI intent
+item, and it will contain the attribute name.
+
+For an PPTR_SET or PPTR_REMOVE opcode, there should be two regions after the
+ATTRI intent item. The first region contains the dirent name as the attribute
+name. The second region contains a file handle to the parent directory as the
+attribute value.
+
+For an PPTR_REPLACE opcode, there should be between four regions after the
+ATTRI intent item. The first region contains the dirent name to remove.
+The second region contains the dirent name to create. The third region
+contains the parent directory file handle to remove. The fourth region
+contains the parent directory file handle to add.
+
[[ATTRD_Log_Item]]
=== Completion of Extended Attribute Updates
