Hi,
This patch adds functionality of manipulating by records in attributes tree.
With the best regards,
Vyacheslav Dubeyko.
---
From: Vyacheslav Dubeyko <[email protected]>
Subject: [PATCH v3 3/5] hfsplus: add functionality of manipulating by records in attributes tree
This patch adds functionality of manipulating by records in attributes tree.
Reported-by: Hin-Tak Leung <[email protected]>
Signed-off-by: Vyacheslav Dubeyko <[email protected]>
---
fs/hfsplus/attributes.c | 399 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 399 insertions(+)
create mode 100644 fs/hfsplus/attributes.c
diff --git a/fs/hfsplus/attributes.c b/fs/hfsplus/attributes.c
new file mode 100644
index 0000000..8d691f1
--- /dev/null
+++ b/fs/hfsplus/attributes.c
@@ -0,0 +1,399 @@
+/*
+ * linux/fs/hfsplus/attributes.c
+ *
+ * Vyacheslav Dubeyko <[email protected]>
+ *
+ * Handling of records in attributes tree
+ */
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+static struct kmem_cache *hfsplus_attr_tree_cachep;
+
+int hfsplus_create_attr_tree_cache(void)
+{
+ if (hfsplus_attr_tree_cachep)
+ return -EEXIST;
+
+ hfsplus_attr_tree_cachep =
+ kmem_cache_create("hfsplus_attr_cache",
+ sizeof(hfsplus_attr_entry), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!hfsplus_attr_tree_cachep)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void hfsplus_destroy_attr_tree_cache(void)
+{
+ kmem_cache_destroy(hfsplus_attr_tree_cachep);
+}
+
+int hfsplus_attr_bin_cmp_key(const hfsplus_btree_key *k1,
+ const hfsplus_btree_key *k2)
+{
+ __be32 k1_cnid, k2_cnid;
+
+ k1_cnid = k1->attr.cnid;
+ k2_cnid = k2->attr.cnid;
+ if (k1_cnid != k2_cnid)
+ return be32_to_cpu(k1_cnid) < be32_to_cpu(k2_cnid) ? -1 : 1;
+
+ return hfsplus_strcmp(
+ (const struct hfsplus_unistr *)&k1->attr.key_name,
+ (const struct hfsplus_unistr *)&k2->attr.key_name);
+}
+
+int hfsplus_attr_build_key(struct super_block *sb, hfsplus_btree_key *key,
+ u32 cnid, const char *name)
+{
+ int len;
+
+ memset(key, 0, sizeof(struct hfsplus_attr_key));
+ key->attr.cnid = cpu_to_be32(cnid);
+ if (name) {
+ len = strlen(name);
+ if (len > HFSPLUS_ATTR_MAX_STRLEN) {
+ printk(KERN_ERR "hfs: invalid xattr name's length\n");
+ return -EINVAL;
+ }
+ hfsplus_asc2uni(sb,
+ (struct hfsplus_unistr *)&key->attr.key_name,
+ HFSPLUS_ATTR_MAX_STRLEN, name, len);
+ len = be16_to_cpu(key->attr.key_name.length);
+ } else {
+ key->attr.key_name.length = 0;
+ len = 0;
+ }
+
+ /* The length of the key, as stored in key_len field, does not include
+ * the size of the key_len field itself.
+ * So, offsetof(hfsplus_attr_key, key_name) is a trick because
+ * it takes into consideration key_len field (__be16) of
+ * hfsplus_attr_key structure instead of length field (__be16) of
+ * hfsplus_attr_unistr structure.
+ */
+ key->key_len =
+ cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) +
+ 2 * len);
+
+ return 0;
+}
+
+void hfsplus_attr_build_key_uni(hfsplus_btree_key *key,
+ u32 cnid,
+ struct hfsplus_attr_unistr *name)
+{
+ int ustrlen;
+
+ memset(key, 0, sizeof(struct hfsplus_attr_key));
+ ustrlen = be16_to_cpu(name->length);
+ key->attr.cnid = cpu_to_be32(cnid);
+ key->attr.key_name.length = cpu_to_be16(ustrlen);
+ ustrlen *= 2;
+ memcpy(key->attr.key_name.unicode, name->unicode, ustrlen);
+
+ /* The length of the key, as stored in key_len field, does not include
+ * the size of the key_len field itself.
+ * So, offsetof(hfsplus_attr_key, key_name) is a trick because
+ * it takes into consideration key_len field (__be16) of
+ * hfsplus_attr_key structure instead of length field (__be16) of
+ * hfsplus_attr_unistr structure.
+ */
+ key->key_len =
+ cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) +
+ ustrlen);
+}
+
+hfsplus_attr_entry *hfsplus_alloc_attr_entry(void)
+{
+ return kmem_cache_alloc(hfsplus_attr_tree_cachep, GFP_KERNEL);
+}
+
+void hfsplus_destroy_attr_entry(hfsplus_attr_entry *entry)
+{
+ if (entry)
+ kmem_cache_free(hfsplus_attr_tree_cachep, entry);
+}
+
+#define HFSPLUS_INVALID_ATTR_RECORD -1
+
+static int hfsplus_attr_build_record(hfsplus_attr_entry *entry, int record_type,
+ u32 cnid, const void *value, size_t size)
+{
+ if (record_type == HFSPLUS_ATTR_FORK_DATA) {
+ /*
+ * Mac OS X supports only inline data attributes.
+ * Do nothing
+ */
+ memset(entry, 0, sizeof(*entry));
+ return sizeof(struct hfsplus_attr_fork_data);
+ } else if (record_type == HFSPLUS_ATTR_EXTENTS) {
+ /*
+ * Mac OS X supports only inline data attributes.
+ * Do nothing.
+ */
+ memset(entry, 0, sizeof(*entry));
+ return sizeof(struct hfsplus_attr_extents);
+ } else if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
+ u16 len;
+
+ memset(entry, 0, sizeof(struct hfsplus_attr_inline_data));
+ entry->inline_data.record_type = cpu_to_be32(record_type);
+ if (size <= HFSPLUS_MAX_INLINE_DATA_SIZE)
+ len = size;
+ else
+ return HFSPLUS_INVALID_ATTR_RECORD;
+ entry->inline_data.length = cpu_to_be16(len);
+ memcpy(entry->inline_data.raw_bytes, value, len);
+ /*
+ * Align len on two-byte boundary.
+ * It needs to add pad byte if we have odd len.
+ */
+ len = round_up(len, 2);
+ return offsetof(struct hfsplus_attr_inline_data, raw_bytes) +
+ len;
+ } else /* invalid input */
+ memset(entry, 0, sizeof(*entry));
+
+ return HFSPLUS_INVALID_ATTR_RECORD;
+}
+
+int hfsplus_find_attr(struct super_block *sb, u32 cnid,
+ const char *name, struct hfs_find_data *fd)
+{
+ int err = 0;
+
+ dprint(DBG_ATTR_MOD, "find_attr: %s,%d\n", name ? name : NULL, cnid);
+
+ if (!HFSPLUS_SB(sb)->attr_tree) {
+ printk(KERN_ERR "hfs: attributes file doesn't exist\n");
+ return -EINVAL;
+ }
+
+ if (name) {
+ err = hfsplus_attr_build_key(sb, fd->search_key, cnid, name);
+ if (err)
+ goto failed_find_attr;
+ err = hfs_brec_find(fd, hfs_find_rec_by_key);
+ if (err)
+ goto failed_find_attr;
+ } else {
+ err = hfsplus_attr_build_key(sb, fd->search_key, cnid, NULL);
+ if (err)
+ goto failed_find_attr;
+ err = hfs_brec_find(fd, hfs_find_1st_rec_by_cnid);
+ if (err)
+ goto failed_find_attr;
+ }
+
+failed_find_attr:
+ return err;
+}
+
+int hfsplus_attr_exists(struct inode *inode, const char *name)
+{
+ int err = 0;
+ struct super_block *sb = inode->i_sb;
+ struct hfs_find_data fd;
+
+ if (!HFSPLUS_SB(sb)->attr_tree)
+ return 0;
+
+ err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+ if (err)
+ return 0;
+
+ err = hfsplus_find_attr(sb, inode->i_ino, name, &fd);
+ if (err)
+ goto attr_not_found;
+
+ hfs_find_exit(&fd);
+ return 1;
+
+attr_not_found:
+ hfs_find_exit(&fd);
+ return 0;
+}
+
+int hfsplus_create_attr(struct inode *inode,
+ const char *name,
+ const void *value, size_t size)
+{
+ struct super_block *sb = inode->i_sb;
+ struct hfs_find_data fd;
+ hfsplus_attr_entry *entry_ptr;
+ int entry_size;
+ int err;
+
+ dprint(DBG_ATTR_MOD, "create_attr: %s,%ld\n",
+ name ? name : NULL, inode->i_ino);
+
+ if (!HFSPLUS_SB(sb)->attr_tree) {
+ printk(KERN_ERR "hfs: attributes file doesn't exist\n");
+ return -EINVAL;
+ }
+
+ entry_ptr = hfsplus_alloc_attr_entry();
+ if (!entry_ptr)
+ return -ENOMEM;
+
+ err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+ if (err)
+ goto failed_init_create_attr;
+
+ if (name) {
+ err = hfsplus_attr_build_key(sb, fd.search_key,
+ inode->i_ino, name);
+ if (err)
+ goto failed_create_attr;
+ } else {
+ err = -EINVAL;
+ goto failed_create_attr;
+ }
+
+ /* Mac OS X supports only inline data attributes. */
+ entry_size = hfsplus_attr_build_record(entry_ptr,
+ HFSPLUS_ATTR_INLINE_DATA,
+ inode->i_ino,
+ value, size);
+ if (entry_size == HFSPLUS_INVALID_ATTR_RECORD) {
+ err = -EINVAL;
+ goto failed_create_attr;
+ }
+
+ err = hfs_brec_find(&fd, hfs_find_rec_by_key);
+ if (err != -ENOENT) {
+ if (!err)
+ err = -EEXIST;
+ goto failed_create_attr;
+ }
+
+ err = hfs_brec_insert(&fd, entry_ptr, entry_size);
+ if (err)
+ goto failed_create_attr;
+
+ hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY);
+
+failed_create_attr:
+ hfs_find_exit(&fd);
+
+failed_init_create_attr:
+ hfsplus_destroy_attr_entry(entry_ptr);
+ return err;
+}
+
+static int __hfsplus_delete_attr(struct inode *inode, u32 cnid,
+ struct hfs_find_data *fd)
+{
+ int err = 0;
+ __be32 found_cnid, record_type;
+
+ hfs_bnode_read(fd->bnode, &found_cnid,
+ fd->keyoffset +
+ offsetof(struct hfsplus_attr_key, cnid),
+ sizeof(__be32));
+ if (cnid != be32_to_cpu(found_cnid))
+ return -ENOENT;
+
+ hfs_bnode_read(fd->bnode, &record_type,
+ fd->entryoffset, sizeof(record_type));
+
+ switch (be32_to_cpu(record_type)) {
+ case HFSPLUS_ATTR_INLINE_DATA:
+ /* All is OK. Do nothing. */
+ break;
+ case HFSPLUS_ATTR_FORK_DATA:
+ case HFSPLUS_ATTR_EXTENTS:
+ printk(KERN_ERR "hfs: only inline data xattr are supported\n");
+ return -EOPNOTSUPP;
+ default:
+ printk(KERN_ERR "hfs: invalid extended attribute record\n");
+ return -ENOENT;
+ }
+
+ err = hfs_brec_remove(fd);
+ if (err)
+ return err;
+
+ hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY);
+ return err;
+}
+
+int hfsplus_delete_attr(struct inode *inode, const char *name)
+{
+ int err = 0;
+ struct super_block *sb = inode->i_sb;
+ struct hfs_find_data fd;
+
+ dprint(DBG_ATTR_MOD, "delete_attr: %s,%ld\n",
+ name ? name : NULL, inode->i_ino);
+
+ if (!HFSPLUS_SB(sb)->attr_tree) {
+ printk(KERN_ERR "hfs: attributes file doesn't exist\n");
+ return -EINVAL;
+ }
+
+ err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+ if (err)
+ return err;
+
+ if (name) {
+ err = hfsplus_attr_build_key(sb, fd.search_key,
+ inode->i_ino, name);
+ if (err)
+ goto out;
+ } else {
+ printk(KERN_ERR "hfs: invalid extended attribute name\n");
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = hfs_brec_find(&fd, hfs_find_rec_by_key);
+ if (err)
+ goto out;
+
+ err = __hfsplus_delete_attr(inode, inode->i_ino, &fd);
+ if (err)
+ goto out;
+
+out:
+ hfs_find_exit(&fd);
+ return err;
+}
+
+int hfsplus_delete_all_attrs(struct inode *dir, u32 cnid)
+{
+ int err = 0;
+ struct hfs_find_data fd;
+
+ dprint(DBG_ATTR_MOD, "delete_all_attrs: %d\n", cnid);
+
+ if (!HFSPLUS_SB(dir->i_sb)->attr_tree) {
+ printk(KERN_ERR "hfs: attributes file doesn't exist\n");
+ return -EINVAL;
+ }
+
+ err = hfs_find_init(HFSPLUS_SB(dir->i_sb)->attr_tree, &fd);
+ if (err)
+ return err;
+
+ for (;;) {
+ err = hfsplus_find_attr(dir->i_sb, cnid, NULL, &fd);
+ if (err) {
+ if (err != -ENOENT)
+ printk(KERN_ERR "hfs: xattr search failed.\n");
+ goto end_delete_all;
+ }
+
+ err = __hfsplus_delete_attr(dir, cnid, &fd);
+ if (err)
+ goto end_delete_all;
+ }
+
+end_delete_all:
+ hfs_find_exit(&fd);
+ return err;
+}
--
1.7.9.5