patch-2.4.22 linux-2.4.22/fs/hfsplus/extents.c
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- Lines: 513
- Date:
2003-08-25 04:44:43.000000000 -0700
- Orig file:
linux-2.4.21/fs/hfsplus/extents.c
- Orig date:
1969-12-31 16:00:00.000000000 -0800
diff -urN linux-2.4.21/fs/hfsplus/extents.c linux-2.4.22/fs/hfsplus/extents.c
@@ -0,0 +1,512 @@
+/*
+ * linux/fs/hfsplus/extents.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Handling of Extents both in catalog and extents overflow trees
+ */
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/version.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
+#include <linux/buffer_head.h>
+#endif
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+/* Compare two extents keys, returns 0 on same, pos/neg for difference */
+int hfsplus_cmp_ext_key(hfsplus_btree_key *k1, hfsplus_btree_key *k2)
+{
+ u32 k1id, k2id;
+ u32 k1s, k2s;
+
+ k1id = k1->ext.cnid;
+ k2id = k2->ext.cnid;
+ if (k1id != k2id)
+ return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1;
+
+ if (k1->ext.fork_type != k2->ext.fork_type)
+ return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1;
+
+ k1s = k1->ext.start_block;
+ k2s = k2->ext.start_block;
+ if (k1s == k2s)
+ return 0;
+ return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1;
+}
+
+void hfsplus_fill_ext_key(hfsplus_btree_key *key, u32 cnid,
+ u32 block, u8 type)
+{
+ key->key_len = cpu_to_be16(HFSPLUS_EXT_KEYLEN - 2);
+ key->ext.cnid = cpu_to_be32(cnid);
+ key->ext.start_block = cpu_to_be32(block);
+ key->ext.fork_type = type;
+ key->ext.pad = 0;
+}
+
+static u32 hfsplus_find_extent(hfsplus_extent *extent, u32 off)
+{
+ int i;
+ u32 count;
+
+ for (i = 0; i < 8; extent++, i++) {
+ count = be32_to_cpu(extent->block_count);
+ if (off < count)
+ return be32_to_cpu(extent->start_block) + off;
+ off -= count;
+ }
+ /* panic? */
+ return 0;
+}
+
+static int hfsplus_find_extentry(struct hfsplus_find_data *fd,
+ hfsplus_extent *extent)
+{
+ int res;
+
+ fd->key->ext.cnid = 0;
+ res = hfsplus_btree_find(fd);
+ if (res && res != -ENOENT)
+ return res;
+ if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
+ fd->key->ext.fork_type != fd->search_key->ext.fork_type)
+ return -ENOENT;
+ //if (fd->entrylength != ext_key_size)...
+ hfsplus_bnode_readbytes(fd->bnode, extent, fd->entryoffset, fd->entrylength);
+ return 0;
+}
+
+/* Get a block at iblock for inode, possibly allocating if create */
+int hfsplus_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ struct super_block *sb;
+ hfsplus_extent_rec ext_entry;
+ struct hfsplus_find_data fd;
+ int err = -EIO;
+ u32 ablock, dblock = 0;
+
+ sb = inode->i_sb;
+
+ /* Convert inode block to disk allocation block */
+ ablock = iblock;
+
+ if (ablock >= HFSPLUS_I(inode).total_blocks) {
+ if (ablock > HFSPLUS_I(inode).total_blocks || !create)
+ return -EIO;
+ if (ablock >= HFSPLUS_I(inode).alloc_blocks) {
+ err = hfsplus_extend_file(inode);
+ if (err)
+ return err;
+ }
+ HFSPLUS_I(inode).mmu_private += sb->s_blocksize;
+ HFSPLUS_I(inode).total_blocks++;
+ mark_inode_dirty(inode);
+ } else
+ create = 0;
+
+ if (ablock < HFSPLUS_I(inode).extent_blocks) {
+ dblock = hfsplus_find_extent(HFSPLUS_I(inode).extents, ablock);
+ } else {
+ hfsplus_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
+ hfsplus_fill_ext_key(fd.search_key, inode->i_ino, ablock, HFSPLUS_IS_RSRC(inode) ?
+ HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
+ err = hfsplus_find_extentry(&fd, ext_entry);
+ if (!err)
+ dblock = hfsplus_find_extent(ext_entry, ablock -
+ be32_to_cpu(fd.key->ext.start_block));
+ hfsplus_find_exit(&fd);
+ if (err)
+ return err;
+ }
+
+ if (!dblock)
+ return -EIO;
+ dprint(DBG_EXTENT, "get_block(%lu): %lu - %u\n", inode->i_ino, iblock, dblock);
+
+ map_bh(bh_result, sb, dblock + HFSPLUS_SB(sb).blockoffset);
+ if (create)
+ set_buffer_new(bh_result);
+ return 0;
+}
+
+static void hfsplus_dump_extent(hfsplus_extent *extent)
+{
+ int i;
+
+ dprint(DBG_EXTENT, " ");
+ for (i = 0; i < 8; i++)
+ dprint(DBG_EXTENT, " %u:%u", be32_to_cpu(extent[i].start_block),
+ be32_to_cpu(extent[i].block_count));
+ dprint(DBG_EXTENT, "\n");
+}
+
+static int hfsplus_add_extent(hfsplus_extent *extent, u32 offset,
+ u32 alloc_block, u32 block_count)
+{
+ u32 count, start;
+ int i;
+
+ hfsplus_dump_extent(extent);
+ for (i = 0; i < 8; extent++, i++) {
+ count = be32_to_cpu(extent->block_count);
+ if (offset == count) {
+ start = be32_to_cpu(extent->start_block);
+ if (alloc_block != start + count) {
+ if (++i >= 8)
+ return -ENOSPC;
+ extent++;
+ extent->start_block = cpu_to_be32(alloc_block);
+ } else
+ block_count += count;
+ extent->block_count = cpu_to_be32(block_count);
+ return 0;
+ } else if (offset < count)
+ break;
+ offset -= count;
+ }
+ /* panic? */
+ return -EIO;
+}
+
+void hfsplus_free_blocks(struct super_block *sb, u32 start, u32 count)
+{
+ struct inode *anode;
+ struct buffer_head *bh;
+ int size, blk, off;
+ unsigned long *data, word, m;
+
+ anode = HFSPLUS_SB(sb).alloc_file;
+ size = sb->s_blocksize / sizeof(unsigned long);
+ blk = (start >> sb->s_blocksize_bits) / 8;
+ off = (start & (sb->s_blocksize * 8 - 1)) / 8 / sizeof(unsigned long);
+ m = 1 << (~start & (8 * sizeof(unsigned long) - 1));
+
+ HFSPLUS_SB(sb).free_blocks += count;
+ sb->s_dirt = 1;
+
+ while (count) {
+ bh = hfsplus_getblk(anode, blk);
+ data = (unsigned long *)bh->b_data;
+ do {
+ word = ~be32_to_cpu(data[off]);
+ for (;;) {
+ if (word & m)
+ printk("freeing free block %u\n", start);
+ word |= m;
+ start++;
+ if (!--count) {
+ data[off] = cpu_to_be32(~word);
+ goto done;
+ }
+ if (!(m >>= 1))
+ break;
+ }
+ data[off] = cpu_to_be32(~word);
+ m = 1UL << (8 * sizeof(unsigned long) - 1);
+ } while (++off < size);
+ done:
+ mark_buffer_dirty_inode(bh, anode);
+ brelse(bh);
+ if (++blk >= anode->i_blocks)
+ break;
+ off = 0;
+ }
+ if (count)
+ printk("%u block left to free\n", count);
+}
+
+int hfsplus_free_extents(struct super_block *sb, hfsplus_extent *extent,
+ u32 offset, u32 block_nr)
+{
+ u32 count, start;
+ int i;
+
+ hfsplus_dump_extent(extent);
+ for (i = 0; i < 8; extent++, i++) {
+ count = be32_to_cpu(extent->block_count);
+ if (offset == count)
+ goto found;
+ else if (offset < count)
+ break;
+ offset -= count;
+ }
+ /* panic? */
+ return -EIO;
+found:
+ for (;;) {
+ start = be32_to_cpu(extent->start_block);
+ if (count <= block_nr) {
+ hfsplus_free_blocks(sb, start, count);
+ extent->block_count = 0;
+ extent->start_block = 0;
+ block_nr -= count;
+ } else {
+ count -= block_nr;
+ hfsplus_free_blocks(sb, start + count, block_nr);
+ extent->block_count = cpu_to_be32(count);
+ block_nr = 0;
+ }
+ if (!block_nr || !i)
+ return 0;
+ i--;
+ extent--;
+ count = be32_to_cpu(extent->block_count);
+ }
+}
+
+int hfsplus_free_fork(struct super_block *sb, u32 cnid, hfsplus_fork_raw *fork, int type)
+{
+ struct hfsplus_find_data fd;
+ hfsplus_extent_rec ext_entry;
+ u32 total_blocks, blocks, start;
+ int res, i;
+
+ total_blocks = be32_to_cpu(fork->total_blocks);
+ if (!total_blocks)
+ return 0;
+
+ blocks = 0;
+ for (i = 0; i < 8; i++)
+ blocks += be32_to_cpu(fork->extents[i].block_count);
+
+ res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
+ if (res)
+ return res;
+ if (total_blocks == blocks)
+ return 0;
+
+ hfsplus_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
+ do {
+ hfsplus_fill_ext_key(fd.search_key, cnid,
+ total_blocks, type);
+ res = hfsplus_find_extentry(&fd, ext_entry);
+ if (res)
+ break;
+ start = be32_to_cpu(fd.key->ext.start_block);
+ hfsplus_free_extents(sb, ext_entry,
+ total_blocks - start,
+ total_blocks);
+ hfsplus_bnode_remove_rec(&fd);
+ total_blocks = start;
+ } while (total_blocks > blocks);
+ hfsplus_find_exit(&fd);
+
+ return res;
+}
+
+int hfsplus_extend_file(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct inode *anode = HFSPLUS_SB(sb).alloc_file;
+ struct hfsplus_find_data fd;
+ hfsplus_extent_rec ext_entry;
+ struct buffer_head *bh;
+ u32 blk, blk1, ablock, block_count;
+ unsigned long *data, word, m;
+ int res, size, off, i;
+
+ if (anode->i_size * 8 < HFSPLUS_SB(sb).total_blocks - HFSPLUS_SB(sb).free_blocks + 8) {
+ // extend alloc file
+ BUG();
+ }
+ blk = blk1 = (HFSPLUS_SB(sb).next_alloc >> sb->s_blocksize_bits) / 8;
+ off = (HFSPLUS_SB(sb).next_alloc & (sb->s_blocksize * 8 - 1)) / sizeof(unsigned long) / 8;
+
+ for (;;) {
+ // ignore first off for now...
+ off = 0;
+ bh = hfsplus_getblk(anode, blk);
+ if (blk == anode->i_blocks - 1)
+ size = (HFSPLUS_SB(sb).total_blocks &
+ (sb->s_blocksize * 8 - 1)) /
+ 8 / sizeof(unsigned long);
+ else
+ size = sb->s_blocksize / sizeof(unsigned long);
+ data = (unsigned long *)bh->b_data;
+ do {
+ word = be32_to_cpu(data[off]);
+ if (!~word)
+ continue;
+ m = 1UL << (sizeof(unsigned long) * 8 - 1);
+ for (i = 0; m; i++, m >>= 1) {
+ if (word & m)
+ continue;
+ ablock = (blk << sb->s_blocksize_bits) * 8 +
+ off * sizeof(unsigned long) * 8 + i;
+ block_count = 1;
+ word |= m;
+#if 0
+ while ((m >>= 1) && !(word & m)) {
+ block_count++;
+ word |= m;
+ }
+#endif
+ data[off] = cpu_to_be32(word);
+ mark_buffer_dirty_inode(bh, anode);
+ brelse(bh);
+ goto found;
+ }
+ } while (++off < size);
+ brelse(bh);
+ if (++blk >= anode->i_blocks)
+ blk = 0;
+ if (blk == blk1)
+ return -ENOSPC;
+ }
+
+found:
+ dprint(DBG_EXTENT, "extend %lu: %u,%u\n", inode->i_ino, ablock, block_count);
+ if (HFSPLUS_I(inode).alloc_blocks <= HFSPLUS_I(inode).extent_blocks) {
+ if (!HFSPLUS_I(inode).extent_blocks) {
+ dprint(DBG_EXTENT, "first extents\n");
+ /* no extents yet */
+ HFSPLUS_I(inode).extents[0].start_block = cpu_to_be32(ablock);
+ HFSPLUS_I(inode).extents[0].block_count = cpu_to_be32(block_count);
+ res = 0;
+ } else
+ /* try to append to extents in inode */
+ res = hfsplus_add_extent(HFSPLUS_I(inode).extents,
+ HFSPLUS_I(inode).alloc_blocks,
+ ablock, block_count);
+ if (!res) {
+ hfsplus_dump_extent(HFSPLUS_I(inode).extents);
+ HFSPLUS_I(inode).extent_blocks += block_count;
+ } else if (res == -ENOSPC) {
+ /* create new extent, so find place to insert it */
+ hfsplus_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
+ hfsplus_fill_ext_key(fd.search_key, inode->i_ino,
+ HFSPLUS_I(inode).alloc_blocks,
+ HFSPLUS_IS_RSRC(inode) ?
+ HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
+ res = hfsplus_find_extentry(&fd, ext_entry);
+ if (res && res != -ENOENT) {
+ hfsplus_find_exit(&fd);
+ goto out;
+ }
+ goto insert_extent;
+ }
+ } else {
+ hfsplus_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
+ hfsplus_fill_ext_key(fd.search_key, inode->i_ino,
+ HFSPLUS_I(inode).alloc_blocks,
+ HFSPLUS_IS_RSRC(inode) ?
+ HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
+ res = hfsplus_find_extentry(&fd, ext_entry);
+ if (res) {
+ hfsplus_find_exit(&fd);
+ goto out;
+ }
+
+ res = hfsplus_add_extent(ext_entry, HFSPLUS_I(inode).alloc_blocks -
+ be32_to_cpu(fd.key->ext.start_block),
+ ablock, block_count);
+ if (!res) {
+ hfsplus_dump_extent(ext_entry);
+ hfsplus_bnode_writebytes(fd.bnode, &ext_entry,
+ fd.entryoffset,
+ sizeof(ext_entry));
+ } else if (res == -ENOSPC)
+ goto insert_extent;
+ hfsplus_find_exit(&fd);
+ }
+out:
+ if (!res) {
+ HFSPLUS_I(inode).alloc_blocks += block_count;
+ mark_inode_dirty(inode);
+ HFSPLUS_SB(sb).free_blocks -= block_count;
+ sb->s_dirt = 1;
+ }
+ return res;
+
+insert_extent:
+ dprint(DBG_EXTENT, "insert new extent\n");
+ memset(ext_entry, 0, sizeof(ext_entry));
+ ext_entry[0].start_block = cpu_to_be32(ablock);
+ ext_entry[0].block_count = cpu_to_be32(block_count);
+
+ hfsplus_bnode_insert_rec(&fd, ext_entry, sizeof(ext_entry));
+ hfsplus_find_exit(&fd);
+ res = 0;
+ goto out;
+}
+
+void hfsplus_truncate(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct hfsplus_find_data fd;
+ hfsplus_extent_rec ext_entry;
+ u32 blk_cnt, start;
+ int res;
+
+ dprint(DBG_INODE, "truncate: %lu, %Lu -> %Lu\n", inode->i_ino,
+ (long long)HFSPLUS_I(inode).mmu_private, inode->i_size);
+ if (inode->i_size == HFSPLUS_I(inode).mmu_private)
+ return;
+ if (inode->i_size > HFSPLUS_I(inode).mmu_private) {
+ struct address_space *mapping = inode->i_mapping;
+ struct page *page;
+ u32 size = inode->i_size - 1;
+ int res;
+
+ page = grab_cache_page(mapping, size >> PAGE_CACHE_SHIFT);
+ if (!page)
+ return;
+ size &= PAGE_CACHE_SIZE - 1;
+ size++;
+ res = mapping->a_ops->prepare_write(NULL, page, size, size);
+ if (!res)
+ res = mapping->a_ops->commit_write(NULL, page, size, size);
+ if (res)
+ inode->i_size = HFSPLUS_I(inode).mmu_private;
+ unlock_page(page);
+ page_cache_release(page);
+ mark_inode_dirty(inode);
+ return;
+ }
+ blk_cnt = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
+
+ while (1) {
+ if (HFSPLUS_I(inode).alloc_blocks <= HFSPLUS_I(inode).extent_blocks) {
+ hfsplus_free_extents(sb, HFSPLUS_I(inode).extents,
+ HFSPLUS_I(inode).alloc_blocks,
+ HFSPLUS_I(inode).alloc_blocks - blk_cnt);
+ hfsplus_dump_extent(HFSPLUS_I(inode).extents);
+ HFSPLUS_I(inode).extent_blocks = blk_cnt;
+ break;
+ }
+ hfsplus_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
+ hfsplus_fill_ext_key(fd.search_key, inode->i_ino,
+ HFSPLUS_I(inode).alloc_blocks,
+ HFSPLUS_IS_RSRC(inode) ?
+ HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
+ res = hfsplus_find_extentry(&fd, ext_entry);
+ if (res) {
+ hfsplus_find_exit(&fd);
+ break;
+ }
+ start = be32_to_cpu(fd.key->ext.start_block);
+ hfsplus_free_extents(sb, ext_entry,
+ HFSPLUS_I(inode).alloc_blocks - start,
+ HFSPLUS_I(inode).alloc_blocks - blk_cnt);
+ hfsplus_dump_extent(ext_entry);
+ if (blk_cnt > start) {
+ hfsplus_bnode_writebytes(fd.bnode, &ext_entry,
+ fd.entryoffset,
+ sizeof(ext_entry));
+ hfsplus_find_exit(&fd);
+ break;
+ }
+ HFSPLUS_I(inode).alloc_blocks = start;
+ hfsplus_bnode_remove_rec(&fd);
+ hfsplus_find_exit(&fd);
+ }
+ HFSPLUS_I(inode).mmu_private = inode->i_size;
+ HFSPLUS_I(inode).alloc_blocks = HFSPLUS_I(inode).total_blocks = blk_cnt;
+}
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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)