From: Jeff Dike <jdike@addtoit.com>

Remove dependency on ghash.h.  Remvoe ghash.h, too.

Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/arch/um/kernel/physmem.c |   96 +++++++--------
 25-akpm/include/linux/ghash.h    |  236 ---------------------------------------
 2 files changed, 48 insertions(+), 284 deletions(-)

diff -puN arch/um/kernel/physmem.c~uml-remove-ghash arch/um/kernel/physmem.c
--- 25/arch/um/kernel/physmem.c~uml-remove-ghash	Thu Sep  9 17:17:34 2004
+++ 25-akpm/arch/um/kernel/physmem.c	Thu Sep  9 17:17:34 2004
@@ -4,7 +4,7 @@
  */
 
 #include "linux/mm.h"
-#include "linux/ghash.h"
+#include "linux/rbtree.h"
 #include "linux/slab.h"
 #include "linux/vmalloc.h"
 #include "linux/bootmem.h"
@@ -19,36 +19,8 @@
 #include "kern.h"
 #include "init.h"
 
-#if 0
-static pgd_t physmem_pgd[PTRS_PER_PGD];
-
-static struct phys_desc *lookup_mapping(void *addr)
-{
-	pgd = &physmem_pgd[pgd_index(addr)];
-	if(pgd_none(pgd))
-		return(NULL);
-
-	pmd = pmd_offset(pgd, addr);
-	if(pmd_none(pmd))
-		return(NULL);
-
-	pte = pte_offset_kernel(pmd, addr);
-	return((struct phys_desc *) pte_val(pte));
-}
-
-static struct add_mapping(void *addr, struct phys_desc *new)
-{
-}
-#endif
-
-#define PHYS_HASHSIZE (8192)
-
-struct phys_desc;
-
-DEF_HASH_STRUCTS(virtmem, PHYS_HASHSIZE, struct phys_desc);
-
 struct phys_desc {
-	struct virtmem_ptrs virt_ptrs;
+	struct rb_node rb;
 	int fd;
 	__u64 offset;
 	void *virt;
@@ -56,21 +28,48 @@ struct phys_desc {
 	struct list_head list;
 };
 
-struct virtmem_table virtmem_hash;
+static struct rb_root phys_mappings = RB_ROOT;
 
-static int virt_cmp(void *virt1, void *virt2)
+static struct rb_node **find_rb(void *virt)
 {
-	return(virt1 != virt2);
+	struct rb_node **n = &phys_mappings.rb_node;
+	struct phys_desc *d;
+
+	while(*n != NULL){
+		d = rb_entry(n, struct phys_desc, rb);
+		if(d->virt == virt)
+			return(n);
+
+		if(d->virt > virt)
+			n = &(*n)->rb_left;
+		else
+			n = &(*n)->rb_right;
+	}
+
+	return(n);
 }
 
-static int virt_hash(void *virt)
+static struct phys_desc *find_phys_mapping(void *virt)
 {
-	unsigned long addr = ((unsigned long) virt) >> PAGE_SHIFT;
-	return(addr % PHYS_HASHSIZE);
+	struct rb_node **n = find_rb(virt);
+
+	if(*n == NULL)
+		return(NULL);
+
+	return(rb_entry(n, struct phys_desc, rb));
 }
 
-DEF_HASH(static, virtmem, struct phys_desc, virt_ptrs, void *, virt, virt_cmp,
-	 virt_hash);
+static void insert_phys_mapping(struct phys_desc *desc)
+{
+	struct rb_node **n = find_rb(desc->virt);
+
+	if(*n != NULL)
+		panic("Physical remapping for %p already present",
+		      desc->virt);
+
+	rb_link_node(&desc->rb, (*n)->rb_parent, n);
+	rb_insert_color(&desc->rb, &phys_mappings);
+}
 
 LIST_HEAD(descriptor_mappings);
 
@@ -127,7 +126,8 @@ int physmem_subst_mapping(void *virt, in
 		return(-ENOMEM);
 
 	phys = __pa(virt);
-	if(find_virtmem_hash(&virtmem_hash, virt) != NULL)
+	desc = find_phys_mapping(virt);
+  	if(desc != NULL)
 		panic("Address 0x%p is already substituted\n", virt);
 
 	err = -ENOMEM;
@@ -136,13 +136,12 @@ int physmem_subst_mapping(void *virt, in
 		goto out;
 
 	*desc = ((struct phys_desc)
-		{ .virt_ptrs =	{ NULL, NULL },
-		  .fd =		fd,
+		{ .fd =			fd,
 		  .offset =		offset,
 		  .virt =		virt,
 		  .phys =		__pa(virt),
 		  .list = 		LIST_HEAD_INIT(desc->list) });
-	insert_virtmem_hash(&virtmem_hash, desc);
+	insert_phys_mapping(desc);
 
 	list_add(&desc->list, &fd_maps->pages);
 
@@ -151,7 +150,7 @@ int physmem_subst_mapping(void *virt, in
 	if(!err)
 		goto out;
 
-	remove_virtmem_hash(&virtmem_hash, desc);
+	rb_erase(&desc->rb, &phys_mappings);
 	kfree(desc);
  out:
 	return(err);
@@ -164,7 +163,7 @@ static void remove_mapping(struct phys_d
 	void *virt = desc->virt;
 	int err;
 
-	remove_virtmem_hash(&virtmem_hash, desc);
+	rb_erase(&desc->rb, &phys_mappings);
 	list_del(&desc->list);
 	kfree(desc);
 
@@ -179,7 +178,7 @@ int physmem_remove_mapping(void *virt)
 	struct phys_desc *desc;
 
 	virt = (void *) ((unsigned long) virt & PAGE_MASK);
-	desc = find_virtmem_hash(&virtmem_hash, virt);
+	desc = find_phys_mapping(virt);
 	if(desc == NULL)
 		return(0);
 
@@ -234,7 +233,9 @@ void arch_free_page(struct page *page, i
 
 int is_remapped(void *virt)
 {
-	return(find_virtmem_hash(&virtmem_hash, virt) != NULL);
+  	struct phys_desc *desc = find_phys_mapping(virt);
+
+	return(desc != NULL);
 }
 
 /* Changed during early boot */
@@ -367,8 +368,7 @@ void setup_physmem(unsigned long start, 
 
 int phys_mapping(unsigned long phys, __u64 *offset_out)
 {
-	struct phys_desc *desc = find_virtmem_hash(&virtmem_hash,
-						   __va(phys & PAGE_MASK));
+	struct phys_desc *desc = find_phys_mapping(__va(phys & PAGE_MASK));
 	int fd = -1;
 
 	if(desc != NULL){
diff -puN include/linux/ghash.h~uml-remove-ghash include/linux/ghash.h
--- 25/include/linux/ghash.h~uml-remove-ghash	Thu Sep  9 17:17:34 2004
+++ 25-akpm/include/linux/ghash.h	Thu Sep  9 17:17:34 2004
@@ -1,236 +0,0 @@
-/*
- * include/linux/ghash.h -- generic hashing with fuzzy retrieval
- *
- * (C) 1997 Thomas Schoebel-Theuer
- *
- * The algorithms implemented here seem to be a completely new invention,
- * and I'll publish the fundamentals in a paper.
- */
-
-#ifndef _GHASH_H
-#define _GHASH_H
-/* HASHSIZE _must_ be a power of two!!! */
-
-
-#define DEF_HASH_FUZZY_STRUCTS(NAME,HASHSIZE,TYPE) \
-\
-struct NAME##_table {\
-	TYPE * hashtable[HASHSIZE];\
-	TYPE * sorted_list;\
-	int nr_entries;\
-};\
-\
-struct NAME##_ptrs {\
-	TYPE * next_hash;\
-	TYPE * prev_hash;\
-	TYPE * next_sorted;\
-	TYPE * prev_sorted;\
-};
-
-#define DEF_HASH_FUZZY(LINKAGE,NAME,HASHSIZE,TYPE,PTRS,KEYTYPE,KEY,KEYCMP,KEYEQ,HASHFN)\
-\
-LINKAGE void insert_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\
-{\
-	int ix = HASHFN(elem->KEY);\
-	TYPE ** base = &tbl->hashtable[ix];\
-	TYPE * ptr = *base;\
-	TYPE * prev = NULL;\
-\
-	tbl->nr_entries++;\
-	while(ptr && KEYCMP(ptr->KEY, elem->KEY)) {\
-		base = &ptr->PTRS.next_hash;\
-		prev = ptr;\
-		ptr = *base;\
-	}\
-	elem->PTRS.next_hash = ptr;\
-	elem->PTRS.prev_hash = prev;\
-	if(ptr) {\
-		ptr->PTRS.prev_hash = elem;\
-	}\
-	*base = elem;\
-\
-	ptr = prev;\
-	if(!ptr) {\
-		ptr = tbl->sorted_list;\
-		prev = NULL;\
-	} else {\
-		prev = ptr->PTRS.prev_sorted;\
-	}\
-	while(ptr) {\
-		TYPE * next = ptr->PTRS.next_hash;\
-		if(next && KEYCMP(next->KEY, elem->KEY)) {\
-			prev = ptr;\
-			ptr = next;\
-		} else if(KEYCMP(ptr->KEY, elem->KEY)) {\
-			prev = ptr;\
-			ptr = ptr->PTRS.next_sorted;\
-		} else\
-			break;\
-	}\
-	elem->PTRS.next_sorted = ptr;\
-	elem->PTRS.prev_sorted = prev;\
-	if(ptr) {\
-		ptr->PTRS.prev_sorted = elem;\
-	}\
-	if(prev) {\
-		prev->PTRS.next_sorted = elem;\
-	} else {\
-		tbl->sorted_list = elem;\
-	}\
-}\
-\
-LINKAGE void remove_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\
-{\
-	TYPE * next = elem->PTRS.next_hash;\
-	TYPE * prev = elem->PTRS.prev_hash;\
-\
-	tbl->nr_entries--;\
-	if(next)\
-		next->PTRS.prev_hash = prev;\
-	if(prev)\
-		prev->PTRS.next_hash = next;\
-	else {\
-		int ix = HASHFN(elem->KEY);\
-		tbl->hashtable[ix] = next;\
-	}\
-\
-	next = elem->PTRS.next_sorted;\
-	prev = elem->PTRS.prev_sorted;\
-	if(next)\
-		next->PTRS.prev_sorted = prev;\
-	if(prev)\
-		prev->PTRS.next_sorted = next;\
-	else\
-		tbl->sorted_list = next;\
-}\
-\
-LINKAGE TYPE * find_##NAME##_hash(struct NAME##_table * tbl, KEYTYPE pos)\
-{\
-	int ix = hashfn(pos);\
-	TYPE * ptr = tbl->hashtable[ix];\
-	while(ptr && KEYCMP(ptr->KEY, pos))\
-		ptr = ptr->PTRS.next_hash;\
-	if(ptr && !KEYEQ(ptr->KEY, pos))\
-		ptr = NULL;\
-	return ptr;\
-}\
-\
-LINKAGE TYPE * find_##NAME##_hash_fuzzy(struct NAME##_table * tbl, KEYTYPE pos)\
-{\
-	int ix;\
-	int offset;\
-	TYPE * ptr;\
-	TYPE * next;\
-\
-	ptr = tbl->sorted_list;\
-	if(!ptr || KEYCMP(pos, ptr->KEY))\
-		return NULL;\
-	ix = HASHFN(pos);\
-	offset = HASHSIZE;\
-	do {\
-		offset >>= 1;\
-		next = tbl->hashtable[(ix+offset) & ((HASHSIZE)-1)];\
-		if(next && (KEYCMP(next->KEY, pos) || KEYEQ(next->KEY, pos))\
-		   && KEYCMP(ptr->KEY, next->KEY))\
-			ptr = next;\
-	} while(offset);\
-\
-	for(;;) {\
-		next = ptr->PTRS.next_hash;\
-		if(next) {\
-			if(KEYCMP(next->KEY, pos)) {\
-				ptr = next;\
-				continue;\
-			}\
-		}\
-		next = ptr->PTRS.next_sorted;\
-		if(next && KEYCMP(next->KEY, pos)) {\
-			ptr = next;\
-			continue;\
-		}\
-		return ptr;\
-	}\
-	return NULL;\
-}
-
-/* LINKAGE - empty or "static", depending on whether you want the definitions to
- *	be public or not
- * NAME - a string to stick in names to make this hash table type distinct from
- * 	any others
- * HASHSIZE - number of buckets
- * TYPE - type of data contained in the buckets - must be a structure, one
- * 	field is of type NAME_ptrs, another is the hash key
- * PTRS - TYPE must contain a field of type NAME_ptrs, PTRS is the name of that
- * 	field
- * KEYTYPE - type of the key field within TYPE
- * KEY - name of the key field within TYPE
- * KEYCMP - pointer to function that compares KEYTYPEs to each other - the
- * 	prototype is int KEYCMP(KEYTYPE, KEYTYPE), it returns zero for equal,
- * 	non-zero for not equal
- * HASHFN - the hash function - the prototype is int HASHFN(KEYTYPE),
- * 	it returns a number in the range 0 ... HASHSIZE - 1
- * Call DEF_HASH_STRUCTS, define your hash table as a NAME_table, then call
- * DEF_HASH.
- */
-
-#define DEF_HASH_STRUCTS(NAME,HASHSIZE,TYPE) \
-\
-struct NAME##_table {\
-	TYPE * hashtable[HASHSIZE];\
-	int nr_entries;\
-};\
-\
-struct NAME##_ptrs {\
-	TYPE * next_hash;\
-	TYPE * prev_hash;\
-};
-
-#define DEF_HASH(LINKAGE,NAME,TYPE,PTRS,KEYTYPE,KEY,KEYCMP,HASHFN)\
-\
-LINKAGE void insert_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\
-{\
-	int ix = HASHFN(elem->KEY);\
-	TYPE ** base = &tbl->hashtable[ix];\
-	TYPE * ptr = *base;\
-	TYPE * prev = NULL;\
-\
-	tbl->nr_entries++;\
-	while(ptr && KEYCMP(ptr->KEY, elem->KEY)) {\
-		base = &ptr->PTRS.next_hash;\
-		prev = ptr;\
-		ptr = *base;\
-	}\
-	elem->PTRS.next_hash = ptr;\
-	elem->PTRS.prev_hash = prev;\
-	if(ptr) {\
-		ptr->PTRS.prev_hash = elem;\
-	}\
-	*base = elem;\
-}\
-\
-LINKAGE void remove_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\
-{\
-	TYPE * next = elem->PTRS.next_hash;\
-	TYPE * prev = elem->PTRS.prev_hash;\
-\
-	tbl->nr_entries--;\
-	if(next)\
-		next->PTRS.prev_hash = prev;\
-	if(prev)\
-		prev->PTRS.next_hash = next;\
-	else {\
-		int ix = HASHFN(elem->KEY);\
-		tbl->hashtable[ix] = next;\
-	}\
-}\
-\
-LINKAGE TYPE * find_##NAME##_hash(struct NAME##_table * tbl, KEYTYPE pos)\
-{\
-	int ix = HASHFN(pos);\
-	TYPE * ptr = tbl->hashtable[ix];\
-	while(ptr && KEYCMP(ptr->KEY, pos))\
-		ptr = ptr->PTRS.next_hash;\
-	return ptr;\
-}
-
-#endif
_