diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /fs/hfs/btree.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/hfs/btree.c')
-rw-r--r-- | fs/hfs/btree.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/fs/hfs/btree.c b/fs/hfs/btree.c new file mode 100644 index 000000000..19017d296 --- /dev/null +++ b/fs/hfs/btree.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/hfs/btree.c + * + * Copyright (C) 2001 + * Brad Boyer (flar@allandria.com) + * (C) 2003 Ardis Technologies <roman@ardistech.com> + * + * Handle opening/closing btree + */ + +#include <linux/pagemap.h> +#include <linux/slab.h> +#include <linux/log2.h> + +#include "btree.h" + +/* Get a reference to a B*Tree and do some initial checks */ +struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp keycmp) +{ + struct hfs_btree *tree; + struct hfs_btree_header_rec *head; + struct address_space *mapping; + struct page *page; + unsigned int size; + + tree = kzalloc(sizeof(*tree), GFP_KERNEL); + if (!tree) + return NULL; + + mutex_init(&tree->tree_lock); + spin_lock_init(&tree->hash_lock); + /* Set the correct compare function */ + tree->sb = sb; + tree->cnid = id; + tree->keycmp = keycmp; + + tree->inode = iget_locked(sb, id); + if (!tree->inode) + goto free_tree; + BUG_ON(!(tree->inode->i_state & I_NEW)); + { + struct hfs_mdb *mdb = HFS_SB(sb)->mdb; + HFS_I(tree->inode)->flags = 0; + mutex_init(&HFS_I(tree->inode)->extents_lock); + switch (id) { + case HFS_EXT_CNID: + hfs_inode_read_fork(tree->inode, mdb->drXTExtRec, mdb->drXTFlSize, + mdb->drXTFlSize, be32_to_cpu(mdb->drXTClpSiz)); + if (HFS_I(tree->inode)->alloc_blocks > + HFS_I(tree->inode)->first_blocks) { + pr_err("invalid btree extent records\n"); + unlock_new_inode(tree->inode); + goto free_inode; + } + + tree->inode->i_mapping->a_ops = &hfs_btree_aops; + break; + case HFS_CAT_CNID: + hfs_inode_read_fork(tree->inode, mdb->drCTExtRec, mdb->drCTFlSize, + mdb->drCTFlSize, be32_to_cpu(mdb->drCTClpSiz)); + + if (!HFS_I(tree->inode)->first_blocks) { + pr_err("invalid btree extent records (0 size)\n"); + unlock_new_inode(tree->inode); + goto free_inode; + } + + tree->inode->i_mapping->a_ops = &hfs_btree_aops; + break; + default: + BUG(); + } + } + unlock_new_inode(tree->inode); + + mapping = tree->inode->i_mapping; + page = read_mapping_page(mapping, 0, NULL); + if (IS_ERR(page)) + goto free_inode; + + /* Load the header */ + head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc)); + tree->root = be32_to_cpu(head->root); + tree->leaf_count = be32_to_cpu(head->leaf_count); + tree->leaf_head = be32_to_cpu(head->leaf_head); + tree->leaf_tail = be32_to_cpu(head->leaf_tail); + tree->node_count = be32_to_cpu(head->node_count); + tree->free_nodes = be32_to_cpu(head->free_nodes); + tree->attributes = be32_to_cpu(head->attributes); + tree->node_size = be16_to_cpu(head->node_size); + tree->max_key_len = be16_to_cpu(head->max_key_len); + tree->depth = be16_to_cpu(head->depth); + + size = tree->node_size; + if (!is_power_of_2(size)) + goto fail_page; + if (!tree->node_count) + goto fail_page; + switch (id) { + case HFS_EXT_CNID: + if (tree->max_key_len != HFS_MAX_EXT_KEYLEN) { + pr_err("invalid extent max_key_len %d\n", + tree->max_key_len); + goto fail_page; + } + break; + case HFS_CAT_CNID: + if (tree->max_key_len != HFS_MAX_CAT_KEYLEN) { + pr_err("invalid catalog max_key_len %d\n", + tree->max_key_len); + goto fail_page; + } + break; + default: + BUG(); + } + + tree->node_size_shift = ffs(size) - 1; + tree->pages_per_bnode = (tree->node_size + PAGE_SIZE - 1) >> PAGE_SHIFT; + + kunmap(page); + put_page(page); + return tree; + +fail_page: + put_page(page); +free_inode: + tree->inode->i_mapping->a_ops = &hfs_aops; + iput(tree->inode); +free_tree: + kfree(tree); + return NULL; +} + +/* Release resources used by a btree */ +void hfs_btree_close(struct hfs_btree *tree) +{ + struct hfs_bnode *node; + int i; + + if (!tree) + return; + + for (i = 0; i < NODE_HASH_SIZE; i++) { + while ((node = tree->node_hash[i])) { + tree->node_hash[i] = node->next_hash; + if (atomic_read(&node->refcnt)) + pr_err("node %d:%d still has %d user(s)!\n", + node->tree->cnid, node->this, + atomic_read(&node->refcnt)); + hfs_bnode_free(node); + tree->node_hash_cnt--; + } + } + iput(tree->inode); + kfree(tree); +} + +void hfs_btree_write(struct hfs_btree *tree) +{ + struct hfs_btree_header_rec *head; + struct hfs_bnode *node; + struct page *page; + + node = hfs_bnode_find(tree, 0); + if (IS_ERR(node)) + /* panic? */ + return; + /* Load the header */ + page = node->page[0]; + head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc)); + + head->root = cpu_to_be32(tree->root); + head->leaf_count = cpu_to_be32(tree->leaf_count); + head->leaf_head = cpu_to_be32(tree->leaf_head); + head->leaf_tail = cpu_to_be32(tree->leaf_tail); + head->node_count = cpu_to_be32(tree->node_count); + head->free_nodes = cpu_to_be32(tree->free_nodes); + head->attributes = cpu_to_be32(tree->attributes); + head->depth = cpu_to_be16(tree->depth); + + kunmap(page); + set_page_dirty(page); + hfs_bnode_put(node); +} + +static struct hfs_bnode *hfs_bmap_new_bmap(struct hfs_bnode *prev, u32 idx) +{ + struct hfs_btree *tree = prev->tree; + struct hfs_bnode *node; + struct hfs_bnode_desc desc; + __be32 cnid; + + node = hfs_bnode_create(tree, idx); + if (IS_ERR(node)) + return node; + + if (!tree->free_nodes) + panic("FIXME!!!"); + tree->free_nodes--; + prev->next = idx; + cnid = cpu_to_be32(idx); + hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4); + + node->type = HFS_NODE_MAP; + node->num_recs = 1; + hfs_bnode_clear(node, 0, tree->node_size); + desc.next = 0; + desc.prev = 0; + desc.type = HFS_NODE_MAP; + desc.height = 0; + desc.num_recs = cpu_to_be16(1); + desc.reserved = 0; + hfs_bnode_write(node, &desc, 0, sizeof(desc)); + hfs_bnode_write_u16(node, 14, 0x8000); + hfs_bnode_write_u16(node, tree->node_size - 2, 14); + hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6); + + return node; +} + +/* Make sure @tree has enough space for the @rsvd_nodes */ +int hfs_bmap_reserve(struct hfs_btree *tree, int rsvd_nodes) +{ + struct inode *inode = tree->inode; + u32 count; + int res; + + while (tree->free_nodes < rsvd_nodes) { + res = hfs_extend_file(inode); + if (res) + return res; + HFS_I(inode)->phys_size = inode->i_size = + (loff_t)HFS_I(inode)->alloc_blocks * + HFS_SB(tree->sb)->alloc_blksz; + HFS_I(inode)->fs_blocks = inode->i_size >> + tree->sb->s_blocksize_bits; + inode_set_bytes(inode, inode->i_size); + count = inode->i_size >> tree->node_size_shift; + tree->free_nodes += count - tree->node_count; + tree->node_count = count; + } + return 0; +} + +struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree) +{ + struct hfs_bnode *node, *next_node; + struct page **pagep; + u32 nidx, idx; + unsigned off; + u16 off16; + u16 len; + u8 *data, byte, m; + int i, res; + + res = hfs_bmap_reserve(tree, 1); + if (res) + return ERR_PTR(res); + + nidx = 0; + node = hfs_bnode_find(tree, nidx); + if (IS_ERR(node)) + return node; + len = hfs_brec_lenoff(node, 2, &off16); + off = off16; + + off += node->page_offset; + pagep = node->page + (off >> PAGE_SHIFT); + data = kmap(*pagep); + off &= ~PAGE_MASK; + idx = 0; + + for (;;) { + while (len) { + byte = data[off]; + if (byte != 0xff) { + for (m = 0x80, i = 0; i < 8; m >>= 1, i++) { + if (!(byte & m)) { + idx += i; + data[off] |= m; + set_page_dirty(*pagep); + kunmap(*pagep); + tree->free_nodes--; + mark_inode_dirty(tree->inode); + hfs_bnode_put(node); + return hfs_bnode_create(tree, idx); + } + } + } + if (++off >= PAGE_SIZE) { + kunmap(*pagep); + data = kmap(*++pagep); + off = 0; + } + idx += 8; + len--; + } + kunmap(*pagep); + nidx = node->next; + if (!nidx) { + printk(KERN_DEBUG "create new bmap node...\n"); + next_node = hfs_bmap_new_bmap(node, idx); + } else + next_node = hfs_bnode_find(tree, nidx); + hfs_bnode_put(node); + if (IS_ERR(next_node)) + return next_node; + node = next_node; + + len = hfs_brec_lenoff(node, 0, &off16); + off = off16; + off += node->page_offset; + pagep = node->page + (off >> PAGE_SHIFT); + data = kmap(*pagep); + off &= ~PAGE_MASK; + } +} + +void hfs_bmap_free(struct hfs_bnode *node) +{ + struct hfs_btree *tree; + struct page *page; + u16 off, len; + u32 nidx; + u8 *data, byte, m; + + hfs_dbg(BNODE_MOD, "btree_free_node: %u\n", node->this); + tree = node->tree; + nidx = node->this; + node = hfs_bnode_find(tree, 0); + if (IS_ERR(node)) + return; + len = hfs_brec_lenoff(node, 2, &off); + while (nidx >= len * 8) { + u32 i; + + nidx -= len * 8; + i = node->next; + if (!i) { + /* panic */; + pr_crit("unable to free bnode %u. bmap not found!\n", + node->this); + hfs_bnode_put(node); + return; + } + hfs_bnode_put(node); + node = hfs_bnode_find(tree, i); + if (IS_ERR(node)) + return; + if (node->type != HFS_NODE_MAP) { + /* panic */; + pr_crit("invalid bmap found! (%u,%d)\n", + node->this, node->type); + hfs_bnode_put(node); + return; + } + len = hfs_brec_lenoff(node, 0, &off); + } + off += node->page_offset + nidx / 8; + page = node->page[off >> PAGE_SHIFT]; + data = kmap(page); + off &= ~PAGE_MASK; + m = 1 << (~nidx & 7); + byte = data[off]; + if (!(byte & m)) { + pr_crit("trying to free free bnode %u(%d)\n", + node->this, node->type); + kunmap(page); + hfs_bnode_put(node); + return; + } + data[off] = byte & ~m; + set_page_dirty(page); + kunmap(page); + hfs_bnode_put(node); + tree->free_nodes++; + mark_inode_dirty(tree->inode); +} |