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-rw-r--r--fs/minix/itree_v2.c75
1 files changed, 75 insertions, 0 deletions
diff --git a/fs/minix/itree_v2.c b/fs/minix/itree_v2.c
new file mode 100644
index 000000000..9d00f31a2
--- /dev/null
+++ b/fs/minix/itree_v2.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/buffer_head.h>
+#include "minix.h"
+
+enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */
+
+typedef u32 block_t; /* 32 bit, host order */
+
+static inline unsigned long block_to_cpu(block_t n)
+{
+ return n;
+}
+
+static inline block_t cpu_to_block(unsigned long n)
+{
+ return n;
+}
+
+static inline block_t *i_data(struct inode *inode)
+{
+ return (block_t *)minix_i(inode)->u.i2_data;
+}
+
+#define DIRCOUNT 7
+#define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
+
+static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
+{
+ int n = 0;
+ struct super_block *sb = inode->i_sb;
+
+ if (block < 0) {
+ printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
+ block, sb->s_bdev);
+ return 0;
+ }
+ if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes)
+ return 0;
+
+ if (block < DIRCOUNT) {
+ offsets[n++] = block;
+ } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
+ offsets[n++] = DIRCOUNT;
+ offsets[n++] = block;
+ } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
+ offsets[n++] = DIRCOUNT + 1;
+ offsets[n++] = block / INDIRCOUNT(sb);
+ offsets[n++] = block % INDIRCOUNT(sb);
+ } else {
+ block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
+ offsets[n++] = DIRCOUNT + 2;
+ offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
+ offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
+ offsets[n++] = block % INDIRCOUNT(sb);
+ }
+ return n;
+}
+
+#include "itree_common.c"
+
+int V2_minix_get_block(struct inode * inode, long block,
+ struct buffer_head *bh_result, int create)
+{
+ return get_block(inode, block, bh_result, create);
+}
+
+void V2_minix_truncate(struct inode * inode)
+{
+ truncate(inode);
+}
+
+unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
+{
+ return nblocks(size, sb);
+}