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authorDavid Woodhouse <dwmw2@infradead.org>2007-12-14 22:02:05 -0500
committerDavid Woodhouse <dwmw2@infradead.org>2007-12-14 22:02:05 -0500
commit2a1df5b2bd5328faa21353946587be507067a910 (patch)
treead673b065938e73c5a95df0f50a7d26edef132d5
parent042f3cd5bd362ae05c11591810321a6fd9d5c784 (diff)
mkfs.jffs2.c: use rbtrees for hardlink tracking
I just couldn't live with myself. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
-rw-r--r--Makefile3
-rw-r--r--mkfs.jffs2.c34
-rw-r--r--rbtree.c390
-rw-r--r--rbtree.h168
4 files changed, 582 insertions, 13 deletions
diff --git a/Makefile b/Makefile
index 25e8341..5f0cef6 100644
--- a/Makefile
+++ b/Makefile
@@ -61,7 +61,8 @@ $(BUILDDIR)/mkfs.jffs2: $(BUILDDIR)/crc32.o \
$(BUILDDIR)/mkfs.jffs2.o \
$(BUILDDIR)/compr_zlib.o \
$(BUILDDIR)/compr_lzo.o \
- $(BUILDDIR)/compr.o
+ $(BUILDDIR)/compr.o \
+ $(BUILDDIR)/rbtree.o
$(CC) $(LDFLAGS) -o $@ $^ -lz -llzo2
$(BUILDDIR)/flash_eraseall: $(BUILDDIR)/crc32.o $(BUILDDIR)/flash_eraseall.o
diff --git a/mkfs.jffs2.c b/mkfs.jffs2.c
index 087f8bd..2228ee1 100644
--- a/mkfs.jffs2.c
+++ b/mkfs.jffs2.c
@@ -73,8 +73,9 @@
#include <zlib.h>
#undef crc32
#include "crc32.h"
+#include "rbtree.h"
-/* Do not use the wierd XPG version of basename */
+/* Do not use the weird XPG version of basename */
#undef basename
//#define DMALLOC
@@ -96,10 +97,10 @@ struct filesystem_entry {
struct filesystem_entry *prev; /* Only relevant to non-directories */
struct filesystem_entry *next; /* Only relevant to non-directories */
struct filesystem_entry *files; /* Only relevant to directories */
- struct filesystem_entry *hardlink_next;
+ struct rb_node hardlink_rb;
};
-struct filesystem_entry *hardlinks = NULL;
+struct rb_root hardlinks;
static int out_fd = -1;
static int in_fd = -1;
static char default_rootdir[] = ".";
@@ -115,18 +116,27 @@ static const char *const memory_exhausted = "memory exhausted";
uint32_t find_hardlink(struct filesystem_entry *e)
{
struct filesystem_entry *f;
-
- for (f = hardlinks; f; f = f->hardlink_next) {
- if (f->sb.st_dev == e->sb.st_dev &&
- f->sb.st_ino == e->sb.st_ino) {
+ struct rb_node **n = &hardlinks.rb_node;
+ struct rb_node *parent = NULL;
+
+ while (*n) {
+ parent = *n;
+ f = rb_entry(parent, struct filesystem_entry, hardlink_rb);
+
+ if ((f->sb.st_dev < e->sb.st_dev) ||
+ (f->sb.st_dev == e->sb.st_dev &&
+ f->sb.st_ino < e->sb.st_ino))
+ n = &parent->rb_left;
+ else if ((f->sb.st_dev > e->sb.st_dev) ||
+ (f->sb.st_dev == e->sb.st_dev &&
+ f->sb.st_ino > e->sb.st_ino)) {
+ n = &parent->rb_right;
+ } else
return f->ino;
- }
}
- /* Add it to the list for later */
- e->hardlink_next = hardlinks;
- hardlinks = e;
-
+ rb_link_node(&e->hardlink_rb, parent, n);
+ rb_insert_color(&e->hardlink_rb, &hardlinks);
return 0;
}
diff --git a/rbtree.c b/rbtree.c
new file mode 100644
index 0000000..dd50134
--- /dev/null
+++ b/rbtree.c
@@ -0,0 +1,390 @@
+/*
+ Red Black Trees
+ (C) 1999 Andrea Arcangeli <andrea@suse.de>
+ (C) 2002 David Woodhouse <dwmw2@infradead.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ linux/lib/rbtree.c
+*/
+
+#include <stdlib.h>
+#include "rbtree.h"
+
+static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
+{
+ struct rb_node *right = node->rb_right;
+ struct rb_node *parent = rb_parent(node);
+
+ if ((node->rb_right = right->rb_left))
+ rb_set_parent(right->rb_left, node);
+ right->rb_left = node;
+
+ rb_set_parent(right, parent);
+
+ if (parent)
+ {
+ if (node == parent->rb_left)
+ parent->rb_left = right;
+ else
+ parent->rb_right = right;
+ }
+ else
+ root->rb_node = right;
+ rb_set_parent(node, right);
+}
+
+static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
+{
+ struct rb_node *left = node->rb_left;
+ struct rb_node *parent = rb_parent(node);
+
+ if ((node->rb_left = left->rb_right))
+ rb_set_parent(left->rb_right, node);
+ left->rb_right = node;
+
+ rb_set_parent(left, parent);
+
+ if (parent)
+ {
+ if (node == parent->rb_right)
+ parent->rb_right = left;
+ else
+ parent->rb_left = left;
+ }
+ else
+ root->rb_node = left;
+ rb_set_parent(node, left);
+}
+
+void rb_insert_color(struct rb_node *node, struct rb_root *root)
+{
+ struct rb_node *parent, *gparent;
+
+ while ((parent = rb_parent(node)) && rb_is_red(parent))
+ {
+ gparent = rb_parent(parent);
+
+ if (parent == gparent->rb_left)
+ {
+ {
+ register struct rb_node *uncle = gparent->rb_right;
+ if (uncle && rb_is_red(uncle))
+ {
+ rb_set_black(uncle);
+ rb_set_black(parent);
+ rb_set_red(gparent);
+ node = gparent;
+ continue;
+ }
+ }
+
+ if (parent->rb_right == node)
+ {
+ register struct rb_node *tmp;
+ __rb_rotate_left(parent, root);
+ tmp = parent;
+ parent = node;
+ node = tmp;
+ }
+
+ rb_set_black(parent);
+ rb_set_red(gparent);
+ __rb_rotate_right(gparent, root);
+ } else {
+ {
+ register struct rb_node *uncle = gparent->rb_left;
+ if (uncle && rb_is_red(uncle))
+ {
+ rb_set_black(uncle);
+ rb_set_black(parent);
+ rb_set_red(gparent);
+ node = gparent;
+ continue;
+ }
+ }
+
+ if (parent->rb_left == node)
+ {
+ register struct rb_node *tmp;
+ __rb_rotate_right(parent, root);
+ tmp = parent;
+ parent = node;
+ node = tmp;
+ }
+
+ rb_set_black(parent);
+ rb_set_red(gparent);
+ __rb_rotate_left(gparent, root);
+ }
+ }
+
+ rb_set_black(root->rb_node);
+}
+
+static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
+ struct rb_root *root)
+{
+ struct rb_node *other;
+
+ while ((!node || rb_is_black(node)) && node != root->rb_node)
+ {
+ if (parent->rb_left == node)
+ {
+ other = parent->rb_right;
+ if (rb_is_red(other))
+ {
+ rb_set_black(other);
+ rb_set_red(parent);
+ __rb_rotate_left(parent, root);
+ other = parent->rb_right;
+ }
+ if ((!other->rb_left || rb_is_black(other->rb_left)) &&
+ (!other->rb_right || rb_is_black(other->rb_right)))
+ {
+ rb_set_red(other);
+ node = parent;
+ parent = rb_parent(node);
+ }
+ else
+ {
+ if (!other->rb_right || rb_is_black(other->rb_right))
+ {
+ struct rb_node *o_left;
+ if ((o_left = other->rb_left))
+ rb_set_black(o_left);
+ rb_set_red(other);
+ __rb_rotate_right(other, root);
+ other = parent->rb_right;
+ }
+ rb_set_color(other, rb_color(parent));
+ rb_set_black(parent);
+ if (other->rb_right)
+ rb_set_black(other->rb_right);
+ __rb_rotate_left(parent, root);
+ node = root->rb_node;
+ break;
+ }
+ }
+ else
+ {
+ other = parent->rb_left;
+ if (rb_is_red(other))
+ {
+ rb_set_black(other);
+ rb_set_red(parent);
+ __rb_rotate_right(parent, root);
+ other = parent->rb_left;
+ }
+ if ((!other->rb_left || rb_is_black(other->rb_left)) &&
+ (!other->rb_right || rb_is_black(other->rb_right)))
+ {
+ rb_set_red(other);
+ node = parent;
+ parent = rb_parent(node);
+ }
+ else
+ {
+ if (!other->rb_left || rb_is_black(other->rb_left))
+ {
+ register struct rb_node *o_right;
+ if ((o_right = other->rb_right))
+ rb_set_black(o_right);
+ rb_set_red(other);
+ __rb_rotate_left(other, root);
+ other = parent->rb_left;
+ }
+ rb_set_color(other, rb_color(parent));
+ rb_set_black(parent);
+ if (other->rb_left)
+ rb_set_black(other->rb_left);
+ __rb_rotate_right(parent, root);
+ node = root->rb_node;
+ break;
+ }
+ }
+ }
+ if (node)
+ rb_set_black(node);
+}
+
+void rb_erase(struct rb_node *node, struct rb_root *root)
+{
+ struct rb_node *child, *parent;
+ int color;
+
+ if (!node->rb_left)
+ child = node->rb_right;
+ else if (!node->rb_right)
+ child = node->rb_left;
+ else
+ {
+ struct rb_node *old = node, *left;
+
+ node = node->rb_right;
+ while ((left = node->rb_left) != NULL)
+ node = left;
+ child = node->rb_right;
+ parent = rb_parent(node);
+ color = rb_color(node);
+
+ if (child)
+ rb_set_parent(child, parent);
+ if (parent == old) {
+ parent->rb_right = child;
+ parent = node;
+ } else
+ parent->rb_left = child;
+
+ node->rb_parent_color = old->rb_parent_color;
+ node->rb_right = old->rb_right;
+ node->rb_left = old->rb_left;
+
+ if (rb_parent(old))
+ {
+ if (rb_parent(old)->rb_left == old)
+ rb_parent(old)->rb_left = node;
+ else
+ rb_parent(old)->rb_right = node;
+ } else
+ root->rb_node = node;
+
+ rb_set_parent(old->rb_left, node);
+ if (old->rb_right)
+ rb_set_parent(old->rb_right, node);
+ goto color;
+ }
+
+ parent = rb_parent(node);
+ color = rb_color(node);
+
+ if (child)
+ rb_set_parent(child, parent);
+ if (parent)
+ {
+ if (parent->rb_left == node)
+ parent->rb_left = child;
+ else
+ parent->rb_right = child;
+ }
+ else
+ root->rb_node = child;
+
+ color:
+ if (color == RB_BLACK)
+ __rb_erase_color(child, parent, root);
+}
+
+/*
+ * This function returns the first node (in sort order) of the tree.
+ */
+struct rb_node *rb_first(struct rb_root *root)
+{
+ struct rb_node *n;
+
+ n = root->rb_node;
+ if (!n)
+ return NULL;
+ while (n->rb_left)
+ n = n->rb_left;
+ return n;
+}
+
+struct rb_node *rb_last(struct rb_root *root)
+{
+ struct rb_node *n;
+
+ n = root->rb_node;
+ if (!n)
+ return NULL;
+ while (n->rb_right)
+ n = n->rb_right;
+ return n;
+}
+
+struct rb_node *rb_next(struct rb_node *node)
+{
+ struct rb_node *parent;
+
+ if (rb_parent(node) == node)
+ return NULL;
+
+ /* If we have a right-hand child, go down and then left as far
+ as we can. */
+ if (node->rb_right) {
+ node = node->rb_right;
+ while (node->rb_left)
+ node=node->rb_left;
+ return node;
+ }
+
+ /* No right-hand children. Everything down and left is
+ smaller than us, so any 'next' node must be in the general
+ direction of our parent. Go up the tree; any time the
+ ancestor is a right-hand child of its parent, keep going
+ up. First time it's a left-hand child of its parent, said
+ parent is our 'next' node. */
+ while ((parent = rb_parent(node)) && node == parent->rb_right)
+ node = parent;
+
+ return parent;
+}
+
+struct rb_node *rb_prev(struct rb_node *node)
+{
+ struct rb_node *parent;
+
+ if (rb_parent(node) == node)
+ return NULL;
+
+ /* If we have a left-hand child, go down and then right as far
+ as we can. */
+ if (node->rb_left) {
+ node = node->rb_left;
+ while (node->rb_right)
+ node=node->rb_right;
+ return node;
+ }
+
+ /* No left-hand children. Go up till we find an ancestor which
+ is a right-hand child of its parent */
+ while ((parent = rb_parent(node)) && node == parent->rb_left)
+ node = parent;
+
+ return parent;
+}
+
+void rb_replace_node(struct rb_node *victim, struct rb_node *new,
+ struct rb_root *root)
+{
+ struct rb_node *parent = rb_parent(victim);
+
+ /* Set the surrounding nodes to point to the replacement */
+ if (parent) {
+ if (victim == parent->rb_left)
+ parent->rb_left = new;
+ else
+ parent->rb_right = new;
+ } else {
+ root->rb_node = new;
+ }
+ if (victim->rb_left)
+ rb_set_parent(victim->rb_left, new);
+ if (victim->rb_right)
+ rb_set_parent(victim->rb_right, new);
+
+ /* Copy the pointers/colour from the victim to the replacement */
+ *new = *victim;
+}
diff --git a/rbtree.h b/rbtree.h
new file mode 100644
index 0000000..9597b10
--- /dev/null
+++ b/rbtree.h
@@ -0,0 +1,168 @@
+/*
+ Red Black Trees
+ (C) 1999 Andrea Arcangeli <andrea@suse.de>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ linux/include/linux/rbtree.h
+
+ To use rbtrees you'll have to implement your own insert and search cores.
+ This will avoid us to use callbacks and to drop drammatically performances.
+ I know it's not the cleaner way, but in C (not in C++) to get
+ performances and genericity...
+
+ Some example of insert and search follows here. The search is a plain
+ normal search over an ordered tree. The insert instead must be implemented
+ int two steps: as first thing the code must insert the element in
+ order as a red leaf in the tree, then the support library function
+ rb_insert_color() must be called. Such function will do the
+ not trivial work to rebalance the rbtree if necessary.
+
+-----------------------------------------------------------------------
+static inline struct page * rb_search_page_cache(struct inode * inode,
+ unsigned long offset)
+{
+ struct rb_node * n = inode->i_rb_page_cache.rb_node;
+ struct page * page;
+
+ while (n)
+ {
+ page = rb_entry(n, struct page, rb_page_cache);
+
+ if (offset < page->offset)
+ n = n->rb_left;
+ else if (offset > page->offset)
+ n = n->rb_right;
+ else
+ return page;
+ }
+ return NULL;
+}
+
+static inline struct page * __rb_insert_page_cache(struct inode * inode,
+ unsigned long offset,
+ struct rb_node * node)
+{
+ struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
+ struct rb_node * parent = NULL;
+ struct page * page;
+
+ while (*p)
+ {
+ parent = *p;
+ page = rb_entry(parent, struct page, rb_page_cache);
+
+ if (offset < page->offset)
+ p = &(*p)->rb_left;
+ else if (offset > page->offset)
+ p = &(*p)->rb_right;
+ else
+ return page;
+ }
+
+ rb_link_node(node, parent, p);
+
+ return NULL;
+}
+
+static inline struct page * rb_insert_page_cache(struct inode * inode,
+ unsigned long offset,
+ struct rb_node * node)
+{
+ struct page * ret;
+ if ((ret = __rb_insert_page_cache(inode, offset, node)))
+ goto out;
+ rb_insert_color(node, &inode->i_rb_page_cache);
+ out:
+ return ret;
+}
+-----------------------------------------------------------------------
+*/
+
+#ifndef _LINUX_RBTREE_H
+#define _LINUX_RBTREE_H
+
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+
+struct rb_node
+{
+ unsigned long rb_parent_color;
+#define RB_RED 0
+#define RB_BLACK 1
+ struct rb_node *rb_right;
+ struct rb_node *rb_left;
+} __attribute__((aligned(sizeof(long))));
+ /* The alignment might seem pointless, but allegedly CRIS needs it */
+
+struct rb_root
+{
+ struct rb_node *rb_node;
+};
+
+
+#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3))
+#define rb_color(r) ((r)->rb_parent_color & 1)
+#define rb_is_red(r) (!rb_color(r))
+#define rb_is_black(r) rb_color(r)
+#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0)
+#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)
+
+static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
+{
+ rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
+}
+static inline void rb_set_color(struct rb_node *rb, int color)
+{
+ rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
+}
+
+#define RB_ROOT (struct rb_root) { NULL, }
+
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+ (type *)( (char *)__mptr - offsetof(type,member) );})
+
+#define rb_entry(ptr, type, member) container_of(ptr, type, member)
+
+#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
+#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
+#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
+
+extern void rb_insert_color(struct rb_node *, struct rb_root *);
+extern void rb_erase(struct rb_node *, struct rb_root *);
+
+/* Find logical next and previous nodes in a tree */
+extern struct rb_node *rb_next(struct rb_node *);
+extern struct rb_node *rb_prev(struct rb_node *);
+extern struct rb_node *rb_first(struct rb_root *);
+extern struct rb_node *rb_last(struct rb_root *);
+
+/* Fast replacement of a single node without remove/rebalance/add/rebalance */
+extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
+ struct rb_root *root);
+
+static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
+ struct rb_node ** rb_link)
+{
+ node->rb_parent_color = (unsigned long )parent;
+ node->rb_left = node->rb_right = NULL;
+
+ *rb_link = node;
+}
+
+#endif /* _LINUX_RBTREE_H */