1 files changed, 165 insertions, 0 deletions

diff --git a/fs/qnx4/bitmap.c b/fs/qnx4/bitmap.c
new file mode 100644
index 000000000000..991253927658
--- /dev/null
+++ b/fs/qnx4/bitmap.c
@@ -0,0 +1,165 @@
+/*
+ * QNX4 file system, Linux implementation.
+ *
+ * Version : 0.2.1
+ *
+ * Using parts of the xiafs filesystem.
+ *
+ * History :
+ *
+ * 28-05-1998 by Richard Frowijn : first release.
+ * 20-06-1998 by Frank Denis : basic optimisations.
+ * 25-06-1998 by Frank Denis : qnx4_is_free, qnx4_set_bitmap, qnx4_bmap .
+ * 28-06-1998 by Frank Denis : qnx4_free_inode (to be fixed) .
+ */
+
+#include <linux/config.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/qnx4_fs.h>
+#include <linux/stat.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/buffer_head.h>
+#include <linux/bitops.h>
+
+int qnx4_new_block(struct super_block *sb)
+{
+        return 0;
+}
+
+static void count_bits(register const char *bmPart, register int size,
+                       int *const tf)
+{
+        char b;
+        int tot = *tf;
+
+        if (size > QNX4_BLOCK_SIZE) {
+                size = QNX4_BLOCK_SIZE;
+        }
+        do {
+                b = *bmPart++;
+                if ((b & 1) == 0)
+                        tot++;
+                if ((b & 2) == 0)
+                        tot++;
+                if ((b & 4) == 0)
+                        tot++;
+                if ((b & 8) == 0)
+                        tot++;
+                if ((b & 16) == 0)
+                        tot++;
+                if ((b & 32) == 0)
+                        tot++;
+                if ((b & 64) == 0)
+                        tot++;
+                if ((b & 128) == 0)
+                        tot++;
+                size--;
+        } while (size != 0);
+        *tf = tot;
+}
+
+unsigned long qnx4_count_free_blocks(struct super_block *sb)
+{
+        int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
+        int total = 0;
+        int total_free = 0;
+        int offset = 0;
+        int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
+        struct buffer_head *bh;
+
+        while (total < size) {
+                if ((bh = sb_bread(sb, start + offset)) == NULL) {
+                        printk("qnx4: I/O error in counting free blocks\n");
+                        break;
+                }
+                count_bits(bh->b_data, size - total, &total_free);
+                brelse(bh);
+                total += QNX4_BLOCK_SIZE;
+                offset++;
+        }
+
+        return total_free;
+}
+
+#ifdef CONFIG_QNX4FS_RW
+
+int qnx4_is_free(struct super_block *sb, long block)
+{
+        int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
+        int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
+        struct buffer_head *bh;
+        const char *g;
+        int ret = -EIO;
+
+        start += block / (QNX4_BLOCK_SIZE * 8);
+        QNX4DEBUG(("qnx4: is_free requesting block [%lu], bitmap in block [%lu]\n",
+                   (unsigned long) block, (unsigned long) start));
+        (void) size;            /* CHECKME */
+        bh = sb_bread(sb, start);
+        if (bh == NULL) {
+                return -EIO;
+        }
+        g = bh->b_data + (block % QNX4_BLOCK_SIZE);
+        if (((*g) & (1 << (block % 8))) == 0) {
+                QNX4DEBUG(("qnx4: is_free -> block is free\n"));
+                ret = 1;
+        } else {
+                QNX4DEBUG(("qnx4: is_free -> block is busy\n"));
+                ret = 0;
+        }
+        brelse(bh);
+
+        return ret;
+}
+
+int qnx4_set_bitmap(struct super_block *sb, long block, int busy)
+{
+        int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
+        int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
+        struct buffer_head *bh;
+        char *g;
+
+        start += block / (QNX4_BLOCK_SIZE * 8);
+        QNX4DEBUG(("qnx4: set_bitmap requesting block [%lu], bitmap in block [%lu]\n",
+                   (unsigned long) block, (unsigned long) start));
+        (void) size;            /* CHECKME */
+        bh = sb_bread(sb, start);
+        if (bh == NULL) {
+                return -EIO;
+        }
+        g = bh->b_data + (block % QNX4_BLOCK_SIZE);
+        if (busy == 0) {
+                (*g) &= ~(1 << (block % 8));
+        } else {
+                (*g) |= (1 << (block % 8));
+        }
+        mark_buffer_dirty(bh);
+        brelse(bh);
+
+        return 0;
+}
+
+static void qnx4_clear_inode(struct inode *inode)
+{
+        struct qnx4_inode_entry *qnx4_ino = qnx4_raw_inode(inode);
+        /* What for? */
+        memset(qnx4_ino->di_fname, 0, sizeof qnx4_ino->di_fname);
+        qnx4_ino->di_size = 0;
+        qnx4_ino->di_num_xtnts = 0;
+        qnx4_ino->di_mode = 0;
+        qnx4_ino->di_status = 0;
+}
+
+void qnx4_free_inode(struct inode *inode)
+{
+        if (inode->i_ino < 1) {
+                printk("free_inode: inode 0 or nonexistent inode\n");
+                return;
+        }
+        qnx4_clear_inode(inode);
+        clear_inode(inode);
+}
+
+#endif