--- /dev/null
+/*
+ * blkmap64_rb.c --- Simple rb-tree implementation for bitmaps
+ *
+ * (C)2010 Red Hat, Inc., Lukas Czerner <lczerner@redhat.com>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <fcntl.h>
+#include <time.h>
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+#include "bmap64.h"
+#include "rbtree.h"
+
+#include <limits.h>
+
+struct bmap_rb_extent {
+ struct rb_node node;
+ __u64 start;
+ __u32 count;
+};
+
+struct ext2fs_rb_private {
+ struct rb_root root;
+ struct bmap_rb_extent **wcursor;
+ struct bmap_rb_extent **rcursor;
+};
+
+static int rb_insert_extent(__u64 start, __u64 count,
+ struct ext2fs_rb_private *);
+static void rb_get_new_extent(struct bmap_rb_extent **, __u64, __u64);
+
+/* #define DEBUG_RB */
+
+#ifdef DEBUG_RB
+static void print_tree(struct rb_root *root)
+{
+ struct rb_node *node = NULL;
+ struct bmap_rb_extent *ext;
+
+ printf("\t\t\t=================================\n");
+ node = ext2fs_rb_first(root);
+ for (node = ext2fs_rb_first(root); node != NULL;
+ node = ext2fs_rb_next(node)) {
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+ printf("\t\t\t--> (%llu -> %llu)\n",
+ ext->start, ext->start + ext->count);
+ }
+ printf("\t\t\t=================================\n");
+}
+
+static int check_tree(struct rb_root *root, const char *msg)
+{
+ struct rb_node *new_node, *node, *next;
+ struct bmap_rb_extent *ext, *old = NULL;
+
+ for (node = ext2fs_rb_first(root); node;
+ node = ext2fs_rb_next(node)) {
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+ if (ext->count <= 0) {
+ printf("Tree Error: count is crazy\n");
+ printf("extent: %llu -> %llu (%u)\n", ext->start,
+ ext->start + ext->count, ext->count);
+ goto err_out;
+ }
+ if (ext->start < 0) {
+ printf("Tree Error: start is crazy\n");
+ printf("extent: %llu -> %llu (%u)\n", ext->start,
+ ext->start + ext->count, ext->count);
+ goto err_out;
+ }
+
+ if (old) {
+ if (old->start > ext->start) {
+ printf("Tree Error: start is crazy\n");
+ printf("extent: %llu -> %llu (%u)\n",
+ old->start, old->start + old->count,
+ old->count);
+ printf("extent next: %llu -> %llu (%u)\n",
+ ext->start, ext->start + ext->count,
+ ext->count);
+ goto err_out;
+ }
+ if ((old->start + old->count) >= ext->start) {
+ printf("Tree Error: extent is crazy\n");
+ printf("extent: %llu -> %llu (%u)\n",
+ old->start, old->start + old->count,
+ old->count);
+ printf("extent next: %llu -> %llu (%u)\n",
+ ext->start, ext->start + ext->count,
+ ext->count);
+ goto err_out;
+ }
+ }
+ old = ext;
+ }
+ return 0;
+
+err_out:
+ printf("%s\n", msg);
+ print_tree(root);
+ exit(1);
+}
+#else
+#define check_tree(root, msg) 0
+#define print_tree(root, msg) 0
+#endif
+
+static void rb_get_new_extent(struct bmap_rb_extent **ext, __u64 start,
+ __u64 count)
+{
+ struct bmap_rb_extent *new_ext;
+ int retval;
+
+ retval = ext2fs_get_mem(sizeof (struct bmap_rb_extent),
+ &new_ext);
+ if (retval) {
+ perror("ext2fs_get_mem");
+ exit(1);
+ }
+
+ new_ext->start = start;
+ new_ext->count = count;
+ *ext = new_ext;
+}
+
+inline
+static void rb_free_extent(struct ext2fs_rb_private *bp,
+ struct bmap_rb_extent *ext)
+{
+ if (*bp->wcursor == ext)
+ *bp->wcursor = NULL;
+ if (*bp->rcursor == ext)
+ *bp->rcursor = NULL;
+ ext2fs_free_mem(&ext);
+}
+
+static errcode_t rb_alloc_private_data (ext2fs_generic_bitmap bitmap)
+{
+ struct ext2fs_rb_private *bp;
+ errcode_t retval;
+
+ retval = ext2fs_get_mem(sizeof (struct ext2fs_rb_private), &bp);
+ if (retval)
+ return retval;
+
+ bp->root = RB_ROOT;
+ retval = ext2fs_get_mem(sizeof(struct bmap_rb_extent *), &bp->rcursor);
+ if (retval)
+ return retval;
+ retval = ext2fs_get_mem(sizeof(struct bmap_rb_extent *), &bp->wcursor);
+ if (retval)
+ return retval;
+ *bp->rcursor = NULL;
+ *bp->wcursor = NULL;
+
+ bitmap->private = (void *) bp;
+ return 0;
+}
+
+static errcode_t rb_new_bmap(ext2_filsys fs EXT2FS_ATTR((unused)),
+ ext2fs_generic_bitmap bitmap)
+{
+ errcode_t retval;
+
+ retval = rb_alloc_private_data (bitmap);
+ if (retval)
+ return retval;
+
+ return 0;
+}
+
+static void rb_free_tree(struct rb_root *root)
+{
+ struct bmap_rb_extent *ext;
+ struct rb_node *node, *next;
+
+ for (node = ext2fs_rb_first(root); node; node = next) {
+ next = ext2fs_rb_next(node);
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+ ext2fs_rb_erase(node, root);
+ ext2fs_free_mem(&ext);
+ }
+}
+
+static void rb_free_bmap(ext2fs_generic_bitmap bitmap)
+{
+ struct ext2fs_rb_private *bp;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+
+ rb_free_tree(&bp->root);
+ ext2fs_free_mem(&bp->rcursor);
+ ext2fs_free_mem(&bp->wcursor);
+ ext2fs_free_mem(&bp);
+ bp = 0;
+}
+
+static errcode_t rb_copy_bmap(ext2fs_generic_bitmap src,
+ ext2fs_generic_bitmap dest)
+{
+ struct ext2fs_rb_private *src_bp, *dest_bp;
+ struct bmap_rb_extent *src_ext, *dest_ext;
+ struct rb_node *dest_node, *src_node, *dest_last, **n;
+ errcode_t retval = 0;
+
+ retval = rb_alloc_private_data (dest);
+ if (retval)
+ return retval;
+
+ src_bp = (struct ext2fs_rb_private *) src->private;
+ dest_bp = (struct ext2fs_rb_private *) dest->private;
+ *src_bp->rcursor = NULL;
+ *dest_bp->rcursor = NULL;
+
+ src_node = ext2fs_rb_first(&src_bp->root);
+ while (src_node) {
+ src_ext = ext2fs_rb_entry(src_node, struct bmap_rb_extent, node);
+ retval = ext2fs_get_mem(sizeof (struct bmap_rb_extent),
+ &dest_ext);
+ if (retval)
+ break;
+
+ memcpy(dest_ext, src_ext, sizeof(struct bmap_rb_extent));
+
+ dest_node = &dest_ext->node;
+ n = &dest_bp->root.rb_node;
+
+ dest_last = NULL;
+ if (*n) {
+ dest_last = ext2fs_rb_last(&dest_bp->root);
+ n = &(dest_last)->rb_right;
+ }
+
+ ext2fs_rb_link_node(dest_node, dest_last, n);
+ ext2fs_rb_insert_color(dest_node, &dest_bp->root);
+
+ src_node = ext2fs_rb_next(src_node);
+ }
+
+ return retval;
+}
+
+static void rb_truncate(__u64 new_max, struct rb_root *root)
+{
+ struct bmap_rb_extent *ext;
+ struct rb_node *node;
+
+ node = ext2fs_rb_last(root);
+ while (node) {
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+
+ if ((ext->start + ext->count - 1) <= new_max)
+ break;
+ else if (ext->start > new_max) {
+ ext2fs_rb_erase(node, root);
+ ext2fs_free_mem(&ext);
+ node = ext2fs_rb_last(root);
+ continue;
+ } else
+ ext->count = new_max - ext->start + 1;
+ }
+}
+
+static errcode_t rb_resize_bmap(ext2fs_generic_bitmap bmap,
+ __u64 new_end, __u64 new_real_end)
+{
+ struct ext2fs_rb_private *bp;
+
+ if (new_real_end >= bmap->real_end) {
+ bmap->end = new_end;
+ bmap->real_end = new_real_end;
+ return 0;
+ }
+
+ bp = (struct ext2fs_rb_private *) bmap->private;
+ *bp->rcursor = NULL;
+ *bp->wcursor = NULL;
+
+ /* truncate tree to new_real_end size */
+ rb_truncate(new_real_end, &bp->root);
+
+ bmap->end = new_end;
+ bmap->real_end = new_real_end;
+ return 0;
+
+}
+
+inline static int
+rb_test_bit(struct ext2fs_rb_private *bp, __u64 bit)
+{
+ struct bmap_rb_extent *rcursor;
+ struct rb_node *parent = NULL;
+ struct rb_node **n = &bp->root.rb_node;
+ struct bmap_rb_extent *ext;
+ int i=0;
+
+ rcursor = *bp->rcursor;
+ if (!rcursor)
+ goto search_tree;
+
+ if (bit >= rcursor->start && bit < rcursor->start + rcursor->count)
+ return 1;
+
+ rcursor = *bp->wcursor;
+ if (!rcursor)
+ goto search_tree;
+
+ if (bit >= rcursor->start && bit < rcursor->start + rcursor->count)
+ return 1;
+
+search_tree:
+
+ while (*n) {
+ parent = *n;
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+ if (bit < ext->start)
+ n = &(*n)->rb_left;
+ else if (bit >= (ext->start + ext->count))
+ n = &(*n)->rb_right;
+ else {
+ *bp->rcursor = ext;
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static int rb_insert_extent(__u64 start, __u64 count,
+ struct ext2fs_rb_private *bp)
+{
+ struct rb_root *root = &bp->root;
+ struct rb_node *parent = NULL, **n = &root->rb_node;
+ struct rb_node *new_node, *node, *next;
+ struct bmap_rb_extent *new_ext;
+ struct bmap_rb_extent *ext;
+ int retval = 0;
+
+ ext = *bp->wcursor;
+ if (ext) {
+ if (start >= ext->start &&
+ start <= (ext->start + ext->count))
+ goto got_extent;
+ }
+
+ while (*n) {
+ parent = *n;
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+
+ if (start < ext->start) {
+ n = &(*n)->rb_left;
+ } else if (start > (ext->start + ext->count)) {
+ n = &(*n)->rb_right;
+ } else {
+got_extent:
+ if ((start + count) <= (ext->start + ext->count))
+ return 1;
+
+ if ((ext->start + ext->count) == start)
+ retval = 0;
+ else
+ retval = 1;
+
+ count += (start - ext->start);
+ start = ext->start;
+ new_ext = ext;
+ new_node = &ext->node;
+
+ goto skip_insert;
+ }
+ }
+
+ rb_get_new_extent(&new_ext, start, count);
+
+ new_node = &new_ext->node;
+ ext2fs_rb_link_node(new_node, parent, n);
+ ext2fs_rb_insert_color(new_node, root);
+ *bp->wcursor = new_ext;
+
+ node = ext2fs_rb_prev(new_node);
+ if (node) {
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+ if ((ext->start + ext->count) == start) {
+ start = ext->start;
+ count += ext->count;
+ ext2fs_rb_erase(node, root);
+ rb_free_extent(bp, ext);
+ }
+ }
+
+skip_insert:
+ /* See if we can merge extent to the right */
+ for (node = ext2fs_rb_next(new_node); node != NULL; node = next) {
+ next = ext2fs_rb_next(node);
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+
+ if ((ext->start + ext->count) <= start)
+ continue;
+
+ /* No more merging */
+ if ((start + count) < ext->start)
+ break;
+
+ /* ext is embedded in new_ext interval */
+ if ((start + count) >= (ext->start + ext->count)) {
+ ext2fs_rb_erase(node, root);
+ rb_free_extent(bp, ext);
+ continue;
+ } else {
+ /* merge ext with new_ext */
+ count += ((ext->start + ext->count) -
+ (start + count));
+ ext2fs_rb_erase(node, root);
+ rb_free_extent(bp, ext);
+ break;
+ }
+ }
+
+ new_ext->start = start;
+ new_ext->count = count;
+
+ return retval;
+}
+
+static int rb_remove_extent(__u64 start, __u64 count,
+ struct ext2fs_rb_private *bp)
+{
+ struct rb_root *root = &bp->root;
+ struct rb_node *parent = NULL, **n = &root->rb_node;
+ struct rb_node *node;
+ struct bmap_rb_extent *ext;
+ __u64 new_start, new_count;
+ int retval = 0;
+
+ if (EXT2FS_RB_EMPTY_ROOT(root))
+ return 0;
+
+ while (*n) {
+ parent = *n;
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+ if (start < ext->start) {
+ n = &(*n)->rb_left;
+ continue;
+ } else if (start >= (ext->start + ext->count)) {
+ n = &(*n)->rb_right;
+ continue;
+ }
+
+ if ((start > ext->start) &&
+ (start + count) < (ext->start + ext->count)) {
+ /* We have to split extent into two */
+ new_start = start + count;
+ new_count = (ext->start + ext->count) - new_start;
+
+ ext->count = start - ext->start;
+
+ rb_insert_extent(new_start, new_count, bp);
+ return 1;
+ }
+
+ if ((start + count) >= (ext->start + ext->count)) {
+ ext->count = start - ext->start;
+ retval = 1;
+ }
+
+ if (0 == ext->count) {
+ parent = ext2fs_rb_next(&ext->node);
+ ext2fs_rb_erase(&ext->node, root);
+ rb_free_extent(bp, ext);
+ break;
+ }
+
+ if (start == ext->start) {
+ ext->start += count;
+ ext->count -= count;
+ return 1;
+ }
+ }
+
+ /* See if we should delete or truncate extent on the right */
+ for (; parent != NULL; parent = node) {
+ node = ext2fs_rb_next(parent);
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+ if ((ext->start + ext->count) <= start)
+ continue;
+
+ /* No more extents to be removed/truncated */
+ if ((start + count) < ext->start)
+ break;
+
+ /* The entire extent is within the region to be removed */
+ if ((start + count) >= (ext->start + ext->count)) {
+ ext2fs_rb_erase(parent, root);
+ rb_free_extent(bp, ext);
+ retval = 1;
+ continue;
+ } else {
+ /* modify the last extent in reigon to be removed */
+ ext->count -= ((start + count) - ext->start);
+ ext->start = start + count;
+ retval = 1;
+ break;
+ }
+ }
+
+ return retval;
+}
+
+static int rb_mark_bmap(ext2fs_generic_bitmap bitmap, __u64 arg)
+{
+ struct ext2fs_rb_private *bp;
+ int i;
+
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ arg -= bitmap->start;
+
+ return rb_insert_extent(arg, 1, bp);
+}
+
+static int rb_unmark_bmap(ext2fs_generic_bitmap bitmap, __u64 arg)
+{
+ struct ext2fs_rb_private *bp;
+ int retval;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ arg -= bitmap->start;
+
+ retval = rb_remove_extent(arg, 1, bp);
+ check_tree(&bp->root, __func__);
+
+ return retval;
+}
+
+inline
+static int rb_test_bmap(ext2fs_generic_bitmap bitmap, __u64 arg)
+{
+ struct ext2fs_rb_private *bp;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ arg -= bitmap->start;
+
+ return rb_test_bit(bp, arg);
+}
+
+static void rb_mark_bmap_extent(ext2fs_generic_bitmap bitmap, __u64 arg,
+ unsigned int num)
+{
+ struct ext2fs_rb_private *bp;
+ struct bmap_rb_extent *new_ext;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ arg -= bitmap->start;
+
+ rb_insert_extent(arg, num, bp);
+}
+
+static void rb_unmark_bmap_extent(ext2fs_generic_bitmap bitmap, __u64 arg,
+ unsigned int num)
+{
+ struct ext2fs_rb_private *bp;
+ int ret;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ arg -= bitmap->start;
+
+ rb_remove_extent(arg, num, bp);
+ check_tree(&bp->root, __func__);
+}
+
+static int rb_test_clear_bmap_extent(ext2fs_generic_bitmap bitmap,
+ __u64 start, unsigned int len)
+{
+ struct rb_node *parent = NULL, **n;
+ struct rb_node *node, *next;
+ struct ext2fs_rb_private *bp;
+ struct bmap_rb_extent *ext;
+ int retval = 1;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ n = &bp->root.rb_node;
+ start -= bitmap->start;
+
+ if ((len == 0) || EXT2FS_RB_EMPTY_ROOT(&bp->root))
+ return 1;
+
+ /*
+ * If we find nothing, we should examine whole extent, but
+ * when we find match, the extent is not clean, thus be return
+ * false.
+ */
+ while (*n) {
+ parent = *n;
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+ if (start < ext->start) {
+ n = &(*n)->rb_left;
+ } else if (start >= (ext->start + ext->count)) {
+ n = &(*n)->rb_right;
+ } else {
+ /*
+ * We found extent int the tree -> extent is not
+ * clean
+ */
+ return 0;
+ }
+ }
+
+ node = parent;
+ while (node) {
+ next = ext2fs_rb_next(node);
+ ext = ext2fs_rb_entry(node, struct bmap_rb_extent, node);
+ node = next;
+
+ if ((ext->start + ext->count) <= start)
+ continue;
+
+ /* No more merging */
+ if ((start + len) <= ext->start)
+ break;
+
+ retval = 0;
+ break;
+ }
+ return retval;
+}
+
+static errcode_t rb_set_bmap_range(ext2fs_generic_bitmap bitmap,
+ __u64 start, size_t num, void *in)
+{
+ struct ext2fs_rb_private *bp;
+ size_t i;
+ int ret;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+
+ for (i = 0; i < num; i++) {
+ ret = ext2fs_test_bit(i, in);
+ if (ret)
+ rb_insert_extent(start + i - bitmap->start, 1, bp);
+ }
+
+ return 0;
+}
+
+static errcode_t rb_get_bmap_range(ext2fs_generic_bitmap bitmap,
+ __u64 start, size_t num, void *out)
+{
+
+ struct rb_node *parent = NULL, *next, **n;
+ struct ext2fs_rb_private *bp;
+ struct bmap_rb_extent *ext;
+ __u64 pos;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+ n = &bp->root.rb_node;
+ start -= bitmap->start;
+
+ if (EXT2FS_RB_EMPTY_ROOT(&bp->root))
+ return 0;
+
+ while (*n) {
+ parent = *n;
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+ if (start < ext->start) {
+ n = &(*n)->rb_left;
+ } else if (start >= (ext->start + ext->count)) {
+ n = &(*n)->rb_right;
+ } else
+ break;
+ }
+
+ pos = start;
+ for (; parent != NULL; parent = next) {
+ next = ext2fs_rb_next(parent);
+ ext = ext2fs_rb_entry(parent, struct bmap_rb_extent, node);
+
+ while (((pos - start) < num) &&
+ (pos < ext->start)) {
+ ext2fs_fast_clear_bit64((pos - start), out);
+ pos++;
+ }
+
+ if ((pos - start) >= num)
+ return 0;
+
+ while (((pos - start) < num) &&
+ (pos < (ext->start + ext->count))) {
+ ext2fs_fast_set_bit64((pos - start), out);
+ pos++;
+ }
+ }
+
+ while ((pos - start) < num) {
+ ext2fs_fast_clear_bit64((pos - start), out);
+ pos++;
+ }
+
+ return 0;
+}
+
+static void rb_clear_bmap(ext2fs_generic_bitmap bitmap)
+{
+ struct ext2fs_rb_private *bp;
+
+ bp = (struct ext2fs_rb_private *) bitmap->private;
+
+ rb_free_tree(&bp->root);
+ *bp->rcursor = NULL;
+ *bp->wcursor = NULL;
+}
+
+struct ext2_bitmap_ops ext2fs_blkmap64_rbtree = {
+ .type = EXT2FS_BMAP64_RBTREE,
+ .new_bmap = rb_new_bmap,
+ .free_bmap = rb_free_bmap,
+ .copy_bmap = rb_copy_bmap,
+ .resize_bmap = rb_resize_bmap,
+ .mark_bmap = rb_mark_bmap,
+ .unmark_bmap = rb_unmark_bmap,
+ .test_bmap = rb_test_bmap,
+ .test_clear_bmap_extent = rb_test_clear_bmap_extent,
+ .mark_bmap_extent = rb_mark_bmap_extent,
+ .unmark_bmap_extent = rb_unmark_bmap_extent,
+ .set_bmap_range = rb_set_bmap_range,
+ .get_bmap_range = rb_get_bmap_range,
+ .clear_bmap = rb_clear_bmap,
+};