ref: 15ace36d9b3bcb9699b5aed7196916de8694de6c
parent: 18bebd19be943691e06249887ed3752279cde5b1
author: ngkaho1234 <[email protected]>
date: Mon Oct 5 20:02:35 EDT 2015
ext4_fs_set_xattr, ext4_fs_get_xattr and ext4_fs_remove_xattr introduced.(EXPERIMENTAL, POTENTIAL DEADLOCKgit add .
--- a/lwext4/ext4.c
+++ b/lwext4/ext4.c
@@ -739,7 +739,17 @@
private_ret = ext4_fs_get_xattr_ref(&f->mp->fs, &ref,
&xattr_ref);
if (private_ret == EOK) {+#define EXT4_XATTR_TEST_DATA_SIZE 1024
+#define EXT4_XATTR_TEST_NAME "bad_boy"
+ static char test_data[EXT4_XATTR_TEST_DATA_SIZE] = {'a'};ext4_dmask_set(EXT4_DEBUG_ALL);
+ /*ext4_fs_set_xattr(&xattr_ref,*/
+ /*EXT4_XATTR_INDEX_USER,*/
+ /*EXT4_XATTR_TEST_NAME,*/
+ /*strlen(EXT4_XATTR_TEST_NAME),*/
+ /*test_data,*/
+ /*EXT4_XATTR_TEST_DATA_SIZE,*/
+ /*0);*/
ext4_fs_put_xattr_ref(&xattr_ref);
}
}
--- a/lwext4/ext4_errno.h
+++ b/lwext4/ext4_errno.h
@@ -76,6 +76,8 @@
#define EDOM 33 /* Math argument out of domain of func */
#define ERANGE 34 /* Math result not representable */
#define ENOTEMPTY 39 /* Directory not empty */
+#define ENODATA 61 /* No data available */
+#define ENOATTR ENODATA /* No attribute available */
#define ENOTSUP 95 /* Not supported */
#endif
--- a/lwext4/ext4_xattr.c
+++ b/lwext4/ext4_xattr.c
@@ -90,6 +90,35 @@
entry->e_hash = to_le32(hash);
}
+#define BLOCK_HASH_SHIFT 16
+
+/*
+ * ext4_xattr_rehash()
+ *
+ * Re-compute the extended attribute hash value after an entry has changed.
+ */
+static void ext4_xattr_rehash(struct ext4_xattr_header *header,
+ struct ext4_xattr_entry *entry)
+{+ struct ext4_xattr_entry *here;
+ uint32_t hash = 0;
+
+ ext4_xattr_compute_hash(header, entry);
+ here = EXT4_XATTR_ENTRY(header+1);
+ while (!EXT4_XATTR_IS_LAST_ENTRY(here)) {+ if (!here->e_hash) {+ /* Block is not shared if an entry's hash value == 0 */
+ hash = 0;
+ break;
+ }
+ hash = (hash << BLOCK_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
+ to_le32(here->e_hash);
+ here = EXT4_XATTR_NEXT(here);
+ }
+ header->h_hash = to_le32(hash);
+}
+
static int ext4_xattr_item_cmp(struct ext4_xattr_item *a,
struct ext4_xattr_item *b)
{@@ -260,7 +289,8 @@
goto Finish;
}
RB_INSERT(ext4_xattr_tree, &xattr_ref->root, item);
- xattr_ref->ea_size += item->data_size;
+ xattr_ref->ea_size += EXT4_XATTR_SIZE(item->data_size) +
+ EXT4_XATTR_LEN(item->name_len);
}
Finish:
@@ -312,7 +342,8 @@
goto Finish;
}
RB_INSERT(ext4_xattr_tree, &xattr_ref->root, item);
- xattr_ref->ea_size += item->data_size;
+ xattr_ref->ea_size += EXT4_XATTR_SIZE(item->data_size) +
+ EXT4_XATTR_LEN(item->name_len);
}
Finish:
@@ -379,14 +410,7 @@
void *data,
size_t data_size)
{- struct ext4_xattr_item *item =
- ext4_xattr_lookup_item(xattr_ref,
- name_index,
- name,
- name_len);
- if (item)
- return item;
-
+ struct ext4_xattr_item *item;
item = ext4_xattr_item_alloc(name_index,
name,
name_len);
@@ -535,6 +559,7 @@
ext4_xattr_write_to_disk(struct ext4_xattr_ref *xattr_ref)
{int ret = EOK;
+ bool block_modified = false;
void *ibody_data, *block_data;
struct ext4_xattr_item *item, *save_item;
size_t inode_size_rem, block_size_rem;
@@ -545,7 +570,7 @@
inode_size_rem = ext4_xattr_inode_space(xattr_ref);
block_size_rem = ext4_xattr_block_space(xattr_ref);
- if (inode_size_rem) {+ if (inode_size_rem > sizeof(struct ext4_xattr_ibody_header)) {ibody_header = EXT4_XATTR_IHDR(xattr_ref->inode_ref->inode);
entry = EXT4_XATTR_IFIRST(ibody_header);
}
@@ -557,6 +582,7 @@
ibody_header->h_magic = EXT4_XATTR_MAGIC;
xattr_ref->inode_ref->dirty = true;
ibody_data = (char *)ibody_header + inode_size_rem;
+ inode_size_rem -= sizeof(struct ext4_xattr_ibody_header);
}
/* If we need an extra block to hold the EA entries*/
if (xattr_ref->ea_size > inode_size_rem) {@@ -573,6 +599,7 @@
header->h_refcount = to_le32(1);
header->h_blocks = to_le32(1);
block_data = (char *)header + block_size_rem;
+ block_size_rem -= sizeof(struct ext4_xattr_header);
xattr_ref->block.dirty = true;
} else {/* We don't need an extra block.*/
@@ -587,6 +614,7 @@
xattr_ref->block.dirty = true;
block_entry = EXT4_XATTR_BFIRST(&xattr_ref->block);
block_data = (char *)header + block_size_rem;
+ block_size_rem -= sizeof(struct ext4_xattr_header);
}
}
}
@@ -630,8 +658,13 @@
block_size_rem -=
EXT4_XATTR_SIZE(item->data_size) +
EXT4_XATTR_LEN(item->name_len);
+ block_modified = true;
}
xattr_ref->dirty = false;
+ if (block_modified) {+ ext4_xattr_rehash(header,
+ EXT4_XATTR_BFIRST(&xattr_ref->block));
+ }
}
Finish:
@@ -638,6 +671,99 @@
return ret;
}
+
+int ext4_fs_set_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len,
+ void *data,
+ size_t data_size,
+ bool replace)
+{+ int ret = EOK;
+ struct ext4_xattr_item *item =
+ ext4_xattr_lookup_item(ref,
+ name_index,
+ name,
+ name_len);
+ if (replace) {+ if (!item) {+ ret = ENOATTR;
+ goto Finish;
+ }
+ if (item->data_size != data_size)
+ ret = ext4_xattr_resize_item(ref,
+ item,
+ data_size);
+
+ if (ret != EOK) {+ goto Finish;
+ }
+ memcpy(item->data, data, data_size);
+ } else {+ if (item) {+ ret = EEXIST;
+ goto Finish;
+ }
+ item = ext4_xattr_insert_item(ref,
+ name_index,
+ name,
+ name_len,
+ data,
+ data_size);
+ if (!item)
+ ret = ENOMEM;
+
+ }
+Finish:
+ return ret;
+}
+
+int ext4_fs_remove_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len)
+{+ return ext4_xattr_remove_item(ref,
+ name_index,
+ name,
+ name_len);
+}
+
+int ext4_fs_get_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len,
+ void *buf,
+ size_t buf_size,
+ size_t *size_got)
+{+ int ret = EOK;
+ size_t item_size = 0;
+ struct ext4_xattr_item *item =
+ ext4_xattr_lookup_item(ref,
+ name_index,
+ name,
+ name_len);
+
+ if (!item) {+ ret = ENOATTR;
+ goto Finish;
+ }
+ item_size = item->data_size;
+ if (buf_size > item_size)
+ buf_size = item_size;
+
+ if (buf)
+ memcpy(buf, item->data, buf_size);
+
+Finish:
+ if (size_got)
+ *size_got = buf_size;
+
+ return ret;
+}
+
int ext4_fs_get_xattr_ref(struct ext4_fs *fs,
struct ext4_inode_ref *inode_ref,
struct ext4_xattr_ref *ref)
@@ -662,7 +788,8 @@
ref->inode_ref = inode_ref;
ref->fs = fs;
- if (ext4_xattr_inode_space(ref))
+ if (ext4_xattr_inode_space(ref) >
+ sizeof(struct ext4_xattr_ibody_header))
ref->ea_size += sizeof(struct ext4_xattr_ibody_header);
rc = ext4_xattr_fetch(ref);
@@ -683,6 +810,7 @@
ext4_block_set(ref->fs->bdev, &ref->block);
ref->block_loaded = false;
}
+ ext4_xattr_write_to_disk(ref);
ext4_xattr_purge_items(ref);
ref->inode_ref = NULL;
ref->fs = NULL;
--- a/lwext4/ext4_xattr.h
+++ b/lwext4/ext4_xattr.h
@@ -10,4 +10,25 @@
void ext4_fs_put_xattr_ref(struct ext4_xattr_ref *ref);
+int ext4_fs_set_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len,
+ void *data,
+ size_t data_size,
+ bool replace);
+
+int ext4_fs_remove_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len);
+
+int ext4_fs_get_xattr(struct ext4_xattr_ref *ref,
+ uint8_t name_index,
+ char *name,
+ size_t name_len,
+ void *buf,
+ size_t buf_size,
+ size_t *size_got);
+
#endif