OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
862a03c35e
linux/fs/hfs/bnode.c
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00

485 lines
11 KiB
C
Raw Blame History

/*
* linux/fs/hfs/bnode.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Handle basic btree node operations
*/
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include "btree.h"
void hfs_bnode_read(struct hfs_bnode *node, void *buf,
int off, int len)
{
struct page *page;
off += node->page_offset;
page = node->page[0];
memcpy(buf, kmap(page) + off, len);
kunmap(page);
}
u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
{
__be16 data;
// optimize later...
hfs_bnode_read(node, &data, off, 2);
return be16_to_cpu(data);
}
u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
{
u8 data;
// optimize later...
hfs_bnode_read(node, &data, off, 1);
return data;
}
void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
{
struct hfs_btree *tree;
int key_len;
tree = node->tree;
if (node->type == HFS_NODE_LEAF ||
tree->attributes & HFS_TREE_VARIDXKEYS)
key_len = hfs_bnode_read_u8(node, off) + 1;
else
key_len = tree->max_key_len + 1;
hfs_bnode_read(node, key, off, key_len);
}
void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
{
struct page *page;
off += node->page_offset;
page = node->page[0];
memcpy(kmap(page) + off, buf, len);
kunmap(page);
set_page_dirty(page);
}
void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
{
__be16 v = cpu_to_be16(data);
// optimize later...
hfs_bnode_write(node, &v, off, 2);
}
void hfs_bnode_write_u8(struct hfs_bnode *node, int off, u8 data)
{
// optimize later...
hfs_bnode_write(node, &data, off, 1);
}
void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
{
struct page *page;
off += node->page_offset;
page = node->page[0];
memset(kmap(page) + off, 0, len);
kunmap(page);
set_page_dirty(page);
}
void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
struct hfs_bnode *src_node, int src, int len)
{
struct hfs_btree *tree;
struct page *src_page, *dst_page;
hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
if (!len)
return;
tree = src_node->tree;
src += src_node->page_offset;
dst += dst_node->page_offset;
src_page = src_node->page[0];
dst_page = dst_node->page[0];
memcpy(kmap(dst_page) + dst, kmap(src_page) + src, len);
kunmap(src_page);
kunmap(dst_page);
set_page_dirty(dst_page);
}
void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
{
struct page *page;
void *ptr;
hfs_dbg(BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
if (!len)
return;
src += node->page_offset;
dst += node->page_offset;
page = node->page[0];
ptr = kmap(page);
memmove(ptr + dst, ptr + src, len);
kunmap(page);
set_page_dirty(page);
}
void hfs_bnode_dump(struct hfs_bnode *node)
{
struct hfs_bnode_desc desc;
__be32 cnid;
int i, off, key_off;
hfs_dbg(BNODE_MOD, "bnode: %d\n", node->this);
hfs_bnode_read(node, &desc, 0, sizeof(desc));
hfs_dbg(BNODE_MOD, "%d, %d, %d, %d, %d\n",
be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
desc.type, desc.height, be16_to_cpu(desc.num_recs));
off = node->tree->node_size - 2;
for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
key_off = hfs_bnode_read_u16(node, off);
hfs_dbg_cont(BNODE_MOD, " %d", key_off);
if (i && node->type == HFS_NODE_INDEX) {
int tmp;
if (node->tree->attributes & HFS_TREE_VARIDXKEYS)
tmp = (hfs_bnode_read_u8(node, key_off) | 1) + 1;
else
tmp = node->tree->max_key_len + 1;
hfs_dbg_cont(BNODE_MOD, " (%d,%d",
tmp, hfs_bnode_read_u8(node, key_off));
hfs_bnode_read(node, &cnid, key_off + tmp, 4);
hfs_dbg_cont(BNODE_MOD, ",%d)", be32_to_cpu(cnid));
} else if (i && node->type == HFS_NODE_LEAF) {
int tmp;
tmp = hfs_bnode_read_u8(node, key_off);
hfs_dbg_cont(BNODE_MOD, " (%d)", tmp);
}
}
hfs_dbg_cont(BNODE_MOD, "\n");
}
void hfs_bnode_unlink(struct hfs_bnode *node)
{
struct hfs_btree *tree;
struct hfs_bnode *tmp;
__be32 cnid;
tree = node->tree;
if (node->prev) {
tmp = hfs_bnode_find(tree, node->prev);
if (IS_ERR(tmp))
return;
tmp->next = node->next;
cnid = cpu_to_be32(tmp->next);
hfs_bnode_write(tmp, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
hfs_bnode_put(tmp);
} else if (node->type == HFS_NODE_LEAF)
tree->leaf_head = node->next;
if (node->next) {
tmp = hfs_bnode_find(tree, node->next);
if (IS_ERR(tmp))
return;
tmp->prev = node->prev;
cnid = cpu_to_be32(tmp->prev);
hfs_bnode_write(tmp, &cnid, offsetof(struct hfs_bnode_desc, prev), 4);
hfs_bnode_put(tmp);
} else if (node->type == HFS_NODE_LEAF)
tree->leaf_tail = node->prev;
// move down?
if (!node->prev && !node->next) {
printk(KERN_DEBUG "hfs_btree_del_level\n");
}
if (!node->parent) {
tree->root = 0;
tree->depth = 0;
}
set_bit(HFS_BNODE_DELETED, &node->flags);
}
static inline int hfs_bnode_hash(u32 num)
{
num = (num >> 16) + num;
num += num >> 8;
return num & (NODE_HASH_SIZE - 1);
}
struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
{
struct hfs_bnode *node;
if (cnid >= tree->node_count) {
pr_err("request for non-existent node %d in B*Tree\n", cnid);
return NULL;
}
for (node = tree->node_hash[hfs_bnode_hash(cnid)];
node; node = node->next_hash) {
if (node->this == cnid) {
return node;
}
}
return NULL;
}
static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
{
struct super_block *sb;
struct hfs_bnode *node, *node2;
struct address_space *mapping;
struct page *page;
int size, block, i, hash;
loff_t off;
if (cnid >= tree->node_count) {
pr_err("request for non-existent node %d in B*Tree\n", cnid);
return NULL;
}
sb = tree->inode->i_sb;
size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
sizeof(struct page *);
node = kzalloc(size, GFP_KERNEL);
if (!node)
return NULL;
node->tree = tree;
node->this = cnid;
set_bit(HFS_BNODE_NEW, &node->flags);
atomic_set(&node->refcnt, 1);
hfs_dbg(BNODE_REFS, "new_node(%d:%d): 1\n",
node->tree->cnid, node->this);
init_waitqueue_head(&node->lock_wq);
spin_lock(&tree->hash_lock);
node2 = hfs_bnode_findhash(tree, cnid);
if (!node2) {
hash = hfs_bnode_hash(cnid);
node->next_hash = tree->node_hash[hash];
tree->node_hash[hash] = node;
tree->node_hash_cnt++;
} else {
spin_unlock(&tree->hash_lock);
kfree(node);
wait_event(node2->lock_wq, !test_bit(HFS_BNODE_NEW, &node2->flags));
return node2;
}
spin_unlock(&tree->hash_lock);
mapping = tree->inode->i_mapping;
off = (loff_t)cnid * tree->node_size;
block = off >> PAGE_SHIFT;
node->page_offset = off & ~PAGE_MASK;
for (i = 0; i < tree->pages_per_bnode; i++) {
page = read_mapping_page(mapping, block++, NULL);
if (IS_ERR(page))
goto fail;
if (PageError(page)) {
put_page(page);
goto fail;
}
node->page[i] = page;
}
return node;
fail:
set_bit(HFS_BNODE_ERROR, &node->flags);
return node;
}
void hfs_bnode_unhash(struct hfs_bnode *node)
{
struct hfs_bnode **p;
hfs_dbg(BNODE_REFS, "remove_node(%d:%d): %d\n",
node->tree->cnid, node->this, atomic_read(&node->refcnt));
for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
*p && *p != node; p = &(*p)->next_hash)
;
BUG_ON(!*p);
*p = node->next_hash;
node->tree->node_hash_cnt--;
}
/* Load a particular node out of a tree */
struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
{
struct hfs_bnode *node;
struct hfs_bnode_desc *desc;
int i, rec_off, off, next_off;
int entry_size, key_size;
spin_lock(&tree->hash_lock);
node = hfs_bnode_findhash(tree, num);
if (node) {
hfs_bnode_get(node);
spin_unlock(&tree->hash_lock);
wait_event(node->lock_wq, !test_bit(HFS_BNODE_NEW, &node->flags));
if (test_bit(HFS_BNODE_ERROR, &node->flags))
goto node_error;
return node;
}
spin_unlock(&tree->hash_lock);
node = __hfs_bnode_create(tree, num);
if (!node)
return ERR_PTR(-ENOMEM);
if (test_bit(HFS_BNODE_ERROR, &node->flags))
goto node_error;
if (!test_bit(HFS_BNODE_NEW, &node->flags))
return node;
desc = (struct hfs_bnode_desc *)(kmap(node->page[0]) + node->page_offset);
node->prev = be32_to_cpu(desc->prev);
node->next = be32_to_cpu(desc->next);
node->num_recs = be16_to_cpu(desc->num_recs);
node->type = desc->type;
node->height = desc->height;
kunmap(node->page[0]);
switch (node->type) {
case HFS_NODE_HEADER:
case HFS_NODE_MAP:
if (node->height != 0)
goto node_error;
break;
case HFS_NODE_LEAF:
if (node->height != 1)
goto node_error;
break;
case HFS_NODE_INDEX:
if (node->height <= 1 || node->height > tree->depth)
goto node_error;
break;
default:
goto node_error;
}
rec_off = tree->node_size - 2;
off = hfs_bnode_read_u16(node, rec_off);
if (off != sizeof(struct hfs_bnode_desc))
goto node_error;
for (i = 1; i <= node->num_recs; off = next_off, i++) {
rec_off -= 2;
next_off = hfs_bnode_read_u16(node, rec_off);
if (next_off <= off ||
next_off > tree->node_size ||
next_off & 1)
goto node_error;
entry_size = next_off - off;
if (node->type != HFS_NODE_INDEX &&
node->type != HFS_NODE_LEAF)
continue;
key_size = hfs_bnode_read_u8(node, off) + 1;
if (key_size >= entry_size /*|| key_size & 1*/)
goto node_error;
}
clear_bit(HFS_BNODE_NEW, &node->flags);
wake_up(&node->lock_wq);
return node;
node_error:
set_bit(HFS_BNODE_ERROR, &node->flags);
clear_bit(HFS_BNODE_NEW, &node->flags);
wake_up(&node->lock_wq);
hfs_bnode_put(node);
return ERR_PTR(-EIO);
}
void hfs_bnode_free(struct hfs_bnode *node)
{
int i;
for (i = 0; i < node->tree->pages_per_bnode; i++)
if (node->page[i])
put_page(node->page[i]);
kfree(node);
}
struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
{
struct hfs_bnode *node;
struct page **pagep;
int i;
spin_lock(&tree->hash_lock);
node = hfs_bnode_findhash(tree, num);
spin_unlock(&tree->hash_lock);
if (node) {
pr_crit("new node %u already hashed?\n", num);
WARN_ON(1);
return node;
}
node = __hfs_bnode_create(tree, num);
if (!node)
return ERR_PTR(-ENOMEM);
if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
hfs_bnode_put(node);
return ERR_PTR(-EIO);
}
pagep = node->page;
memset(kmap(*pagep) + node->page_offset, 0,
min((int)PAGE_SIZE, (int)tree->node_size));
set_page_dirty(*pagep);
kunmap(*pagep);
for (i = 1; i < tree->pages_per_bnode; i++) {
memset(kmap(*++pagep), 0, PAGE_SIZE);
set_page_dirty(*pagep);
kunmap(*pagep);
}
clear_bit(HFS_BNODE_NEW, &node->flags);
wake_up(&node->lock_wq);
return node;
}
void hfs_bnode_get(struct hfs_bnode *node)
{
if (node) {
atomic_inc(&node->refcnt);
hfs_dbg(BNODE_REFS, "get_node(%d:%d): %d\n",
node->tree->cnid, node->this,
atomic_read(&node->refcnt));
}
}
/* Dispose of resources used by a node */
void hfs_bnode_put(struct hfs_bnode *node)
{
if (node) {
struct hfs_btree *tree = node->tree;
int i;
hfs_dbg(BNODE_REFS, "put_node(%d:%d): %d\n",
node->tree->cnid, node->this,
atomic_read(&node->refcnt));
BUG_ON(!atomic_read(&node->refcnt));
if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock))
return;
for (i = 0; i < tree->pages_per_bnode; i++) {
if (!node->page[i])
continue;
mark_page_accessed(node->page[i]);
}
if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
hfs_bnode_unhash(node);
spin_unlock(&tree->hash_lock);
hfs_bmap_free(node);
hfs_bnode_free(node);
return;
}
spin_unlock(&tree->hash_lock);
}
}
Reference in New Issue View Git Blame Copy Permalink