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* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
*/
#ifdef __KERNEL__
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/reiserfs_fs.h>
#include <linux/locks.h>
#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#else
#include "nokernel.h"
#endif
/* args for the create parameter of reiserfs_get_block */
#define GET_BLOCK_NO_CREATE 0 /* don't create new blocks or convert tails */
#define GET_BLOCK_CREATE 1 /* add anything you need to find block */
#define GET_BLOCK_NO_HOLE 2 /* return -ENOENT for file holes */
#define GET_BLOCK_READ_DIRECT 4 /* read the tail if indirect item not found */
//
// initially this function was derived from minix or ext2's analog and
// evolved as the prototype did
//
void reiserfs_delete_inode (struct inode * inode)
{
int jbegin_count = JOURNAL_PER_BALANCE_CNT * 2;
int windex ;
struct reiserfs_transaction_handle th ;
lock_kernel() ;
/* The = 0 happens when we abort creating a new inode for some reason like lack of space.. */
if (INODE_PKEY(inode)->k_objectid != 0) { /* also handles bad_inode case */
down (&inode->i_sem);
journal_begin(&th, inode->i_sb, jbegin_count) ;
windex = push_journal_writer("delete_inode") ;
reiserfs_delete_object (&th, inode);
reiserfs_remove_page_from_flush_list(&th, inode) ;
pop_journal_writer(windex) ;
reiserfs_release_objectid (&th, inode->i_ino);
journal_end(&th, inode->i_sb, jbegin_count) ;
up (&inode->i_sem);
} else {
/* no object items are in the tree */
;
}
clear_inode (inode); /* note this must go after the journal_end to prevent deadlock */
unlock_kernel() ;
}
static void _make_cpu_key (struct cpu_key * key, int version, __u32 dirid, __u32 objectid,
loff_t offset, int type, int length)
{
key->version = version;
key->on_disk_key.k_dir_id = dirid;
key->on_disk_key.k_objectid = objectid;
set_cpu_key_k_offset (key, offset);
set_cpu_key_k_type (key, type);
key->key_length = length;
}
/* take base of inode_key (it comes from inode always) (dirid, objectid) and version from an inode, set
offset and type of key */
void make_cpu_key (struct cpu_key * key, const struct inode * inode, loff_t offset,
int type, int length)
{
_make_cpu_key (key, inode_items_version (inode), le32_to_cpu (INODE_PKEY (inode)->k_dir_id),
le32_to_cpu (INODE_PKEY (inode)->k_objectid),
offset, type, length);
}
//
// when key is 0, do not set version and short key
//
inline void make_le_item_head (struct item_head * ih, struct cpu_key * key, int version,
loff_t offset, int type, int length, int entry_count/*or ih_free_space*/)
{
if (key) {
ih->ih_key.k_dir_id = cpu_to_le32 (key->on_disk_key.k_dir_id);
ih->ih_key.k_objectid = cpu_to_le32 (key->on_disk_key.k_objectid);
}
ih->ih_version = cpu_to_le16 (version);
set_le_ih_k_offset (ih, offset);
set_le_ih_k_type (ih, type);
ih->ih_item_len = cpu_to_le16 (length);
/* set_ih_free_space (ih, 0);*/
// for directory items it is entry count, for directs and stat
// datas - 0xffff, for indirects - 0
ih->u.ih_entry_count = cpu_to_le16 (entry_count);
}
//
// FIXME: we might cache recently accessed indirect item (or at least
// first 15 pointers just like ext2 does
// Ugh. Not too eager for that....
// I cut the code until such time as I see a convincing argument (benchmark).
// I don't want a bloated inode struct..., and I don't like code complexity....
/* cutting the code is fine, since it really isn't in use yet and is easy
** to add back in. But, Vladimir has a really good idea here. Think
** about what happens for reading a file. For each page,
** The VFS layer calls reiserfs_readpage, who searches the tree to find
** an indirect item. This indirect item has X number of pointers, where
** X is a big number if we've done the block allocation right. But,
** we only use one or two of these pointers during each call to readpage,
** needlessly researching again later on.
**
** The size of the cache could be dynamic based on the size of the file.
**
** I'd also like to see us cache the location the stat data item, since
** we are needlessly researching for that frequently.
**
** --chris
*/
/* people who call journal_begin with a page locked must call this
** BEFORE calling journal_begin
*/
static int prevent_flush_page_lock(struct page *page,
struct inode *inode) {
struct reiserfs_page_list *pl ;
struct super_block *s = inode->i_sb ;
/* we don't care if the inode has a stale pointer from an old
** transaction
*/
if(!page || inode->u.reiserfs_i.i_conversion_trans_id != SB_JOURNAL(s)->j_trans_id) {
return 0 ;
}
pl = inode->u.reiserfs_i.i_converted_page ;
if (pl && pl->page == page) {
pl->do_not_lock = 1 ;
}
/* this last part is really important. The address space operations have
** the page locked before they call the journal functions. So it is possible
** for one process to be waiting in flush_pages_before_commit for a
** page, then for the process with the page locked to call journal_begin.
**
** We'll deadlock because the process flushing pages will never notice
** the process with the page locked has called prevent_flush_page_lock.
** So, we wake up the page waiters, even though the page is still locked.
** The process waiting in flush_pages_before_commit must check the
** pl->do_not_lock flag, and stop trying to lock the page.
*/
wake_up(&page->wait) ;
return 0 ;
}
/* people who call journal_end with a page locked must call this
** AFTER calling journal_end
*/
static int allow_flush_page_lock(struct page *page,
struct inode *inode) {
struct reiserfs_page_list *pl ;
struct super_block *s = inode->i_sb ;
/* we don't care if the inode has a stale pointer from an old
** transaction
*/
if(!page || inode->u.reiserfs_i.i_conversion_trans_id != SB_JOURNAL(s)->j_trans_id) {
return 0 ;
}
pl = inode->u.reiserfs_i.i_converted_page ;
if (pl && pl->page == page) {
pl->do_not_lock = 0 ;
}
return 0 ;
}
/* If this page has a file tail in it, and
** it was read in by get_block_create_0, the page data is valid,
** but tail is still sitting in a direct item, and we can't write to
** it. So, look through this page, and check all the mapped buffers
** to make sure they have valid block numbers. Any that don't need
** to be unmapped, so that block_prepare_write will correctly call
** reiserfs_get_block to convert the tail into an unformatted node
*/
static inline void fix_tail_page_for_writing(struct page *page) {
struct buffer_head *head, *next, *bh ;
if (page && page->buffers) {
head = page->buffers ;
bh = head ;
do {
next = bh->b_this_page ;
if (buffer_mapped(bh) && bh->b_blocknr == 0) {
reiserfs_unmap_buffer(bh) ;
}
bh = next ;
} while (bh != head) ;
}
}
/* we need to allocate a block for new unformatted node. Try to figure out
what point in bitmap reiserfs_new_blocknrs should start from. */
static b_blocknr_t find_tag (struct buffer_head * bh, struct item_head * ih,
__u32 * item, int pos_in_item)
{
if (!is_indirect_le_ih (ih))
/* something more complicated could be here */
return bh->b_blocknr;
/* for indirect item: go to left and look for the first non-hole entry in
the indirect item */
if (pos_in_item == I_UNFM_NUM (ih))
pos_in_item --;
while (pos_in_item >= 0) {
if (item [pos_in_item])
return item [pos_in_item];
pos_in_item --;
}
return bh->b_blocknr;
}
/* reiserfs_get_block does not need to allocate a block only if it has been
done already or non-hole position has been found in the indirect item */
static inline int allocation_needed (int retval, b_blocknr_t allocated,
struct item_head * ih,
__u32 * item, int pos_in_item)
{
if (allocated)
return 0;
if (retval == POSITION_FOUND && is_indirect_le_ih (ih) && item[pos_in_item])
return 0;
return 1;
}
static inline int indirect_item_found (int retval, struct item_head * ih)
{
return (retval == POSITION_FOUND) && is_indirect_le_ih (ih);
}
static inline void set_block_dev_mapped (struct buffer_head * bh,
b_blocknr_t block, struct inode * inode)
{
bh->b_dev = inode->i_dev;
bh->b_blocknr = block;
bh->b_state |= (1UL << BH_Mapped);
}
//
// files which were created in the earlier version can not be longer,
// than 2 gb
//
int file_capable (struct inode * inode, long block)
{
if (inode_items_version (inode) != ITEM_VERSION_1 || // it is new file.
block < (1 << (31 - inode->i_sb->s_blocksize_bits))) // old file, but 'block' is inside of 2gb
return 1;
return 0;
}
/*static*/ void restart_transaction(struct reiserfs_transaction_handle *th,
struct inode *inode, struct path *path) {
struct super_block *s = th->t_super ;
int len = th->t_blocks_allocated ;
pathrelse(path) ;
reiserfs_update_sd(th, inode) ;
journal_end(th, s, len) ;
journal_begin(th, s, len) ;
}
// it is called by get_block when create == 0. Returns block number
// for 'block'-th logical block of file. When it hits direct item it
// returns 0 (being called from bmap) or read direct item into piece
// of page (bh_result)
// Please improve the english/clarity in the comment above, as it is
// hard to understand.
static int _get_block_create_0 (struct inode * inode, long block,
struct buffer_head * bh_result,
int args)
{
INITIALIZE_PATH (path);
struct cpu_key key;
struct buffer_head * bh;
struct item_head * ih, tmp_ih;
int fs_gen ;
int blocknr;
char * p = NULL;
int chars;
int ret ;
int done = 0 ;
unsigned long offset ;
// prepare the key to look for the 'block'-th block of file
make_cpu_key (&key, inode,
(loff_t)block * inode->i_sb->s_blocksize + 1, TYPE_ANY, 3);
research:
if (search_for_position_by_key (inode->i_sb, &key, &path) != POSITION_FOUND) {
pathrelse (&path);
if (p)
kunmap(bh_result->b_page) ;
if ((args & GET_BLOCK_NO_HOLE)) {
return -ENOENT ;
}
return 0 ;
}
//
bh = get_bh (&path);
ih = get_ih (&path);
if (is_indirect_le_ih (ih)) {
__u32 * ind_item = (__u32 *)B_I_PITEM (bh, ih);
/* FIXME: here we could cache indirect item or part of it in
the inode to avoid search_by_key in case of subsequent
access to file */
blocknr = le32_to_cpu (ind_item [path.pos_in_item]);
ret = 0 ;
if (blocknr) {
bh_result->b_dev = inode->i_dev;
bh_result->b_blocknr = blocknr;
bh_result->b_state |= (1UL << BH_Mapped);
} else if ((args & GET_BLOCK_NO_HOLE)) {
ret = -ENOENT ;
}
pathrelse (&path);
if (p)
kunmap(bh_result->b_page) ;
return ret ;
}
// requested data are in direct item(s)
if (!(args & GET_BLOCK_READ_DIRECT)) {
// we are called by bmap. FIXME: we can not map block of file
// when it is stored in direct item(s)
pathrelse (&path);
if (p)
kunmap(bh_result->b_page) ;
return -ENOENT;
}
/* if we've got a direct item, and the buffer was uptodate,
** we don't want to pull data off disk again. skip to the
** end, where we map the buffer and return
*/
if (buffer_uptodate(bh_result)) {
goto finished ;
}
// read file tail into part of page
offset = (cpu_key_k_offset(&key) - 1) & (PAGE_CACHE_SIZE - 1) ;
fs_gen = get_generation(inode->i_sb) ;
copy_item_head (&tmp_ih, ih);
/* we only want to kmap if we are reading the tail into the page.
** this is not the common case, so we don't kmap until we are
** sure we need to. But, this means the item might move if
** kmap schedules
*/
p = (char *)kmap(bh_result->b_page) ;
if (fs_changed (fs_gen, inode->i_sb) && item_moved (&tmp_ih, &path)) {
goto research;
}
p += offset ;
memset (p, 0, inode->i_sb->s_blocksize);
do {
if (!is_direct_le_ih (ih)) {
BUG ();
}
/* make sure we don't read more bytes than actually exist in
** the file. This can happen in odd cases where i_size isn't
** correct, and when direct item padding results in a few
** extra bytes at the end of the direct item
*/
if ((le_ih_k_offset(ih) + path.pos_in_item) > inode->i_size)
break ;
if ((le_ih_k_offset(ih) - 1 + ih_item_len(ih)) > inode->i_size) {
chars = inode->i_size - (le_ih_k_offset(ih) - 1) - path.pos_in_item;
done = 1 ;
} else {
chars = le16_to_cpu (ih->ih_item_len) - path.pos_in_item;
}
memcpy (p, B_I_PITEM (bh, ih) + path.pos_in_item, chars);
if (done)
break ;
p += chars;
if (PATH_LAST_POSITION (&path) != (B_NR_ITEMS (bh) - 1))
// we done, if read direct item is not the last item of
// node FIXME: we could try to check right delimiting key
// to see whether direct item continues in the right
// neighbor or rely on i_size
break;
// update key to look for the next piece
set_cpu_key_k_offset (&key, cpu_key_k_offset (&key) + chars);
if (search_for_position_by_key (inode->i_sb, &key, &path) != POSITION_FOUND)
// we read something from tail, even if now we got IO_ERROR
break;
bh = get_bh (&path);
ih = get_ih (&path);
} while (1);
finished:
pathrelse (&path);
bh_result->b_blocknr = 0 ;
bh_result->b_dev = inode->i_dev;
mark_buffer_uptodate (bh_result, 1);
bh_result->b_state |= (1UL << BH_Mapped);
flush_dcache_page(bh_result->b_page) ;
kunmap(bh_result->b_page) ;
return 0;
}
// this is called to create file map. So, _get_block_create_0 will not
// read direct item
int reiserfs_bmap (struct inode * inode, long block,
struct buffer_head * bh_result, int create)
{
if (!file_capable (inode, block))
return -EFBIG;
lock_kernel() ;
/* do not read the direct item */
_get_block_create_0 (inode, block, bh_result, 0) ;
unlock_kernel() ;
return 0;
}
/* special version of get_block that is only used by grab_tail_page right
** now. It is sent to block_prepare_write, and when you try to get a
** block past the end of the file (or a block from a hole) it returns
** -ENOENT instead of a valid buffer. block_prepare_write expects to
** be able to do i/o on the buffers returned, unless an error value
** is also returned.
**
** So, this allows block_prepare_write to be used for reading a single block
** in a page. Where it does not produce a valid page for holes, or past the
** end of the file. This turns out to be exactly what we need for reading
** tails for conversion.
**
** The point of the wrapper is forcing a certain value for create, even
** though the VFS layer is calling this function with create==1. If you
** don't want to send create == GET_BLOCK_NO_HOLE to reiserfs_get_block,
** don't use this function.
*/
static int reiserfs_get_block_create_0 (struct inode * inode, long block,
struct buffer_head * bh_result, int create) {
return reiserfs_get_block(inode, block, bh_result, GET_BLOCK_NO_HOLE) ;
}
/*
** helper function for when reiserfs_get_block is called for a hole
** but the file tail is still in a direct item
** bh_result is the buffer head for the hole
** tail_offset is the offset of the start of the tail in the file
**
** This calls prepare_write, which will start a new transaction
** you should not be in a transaction, or have any paths held when you
** call this.
*/
static int convert_tail_for_hole(struct inode *inode,
struct buffer_head *bh_result,
loff_t tail_offset) {
unsigned long index ;
unsigned long tail_end ;
unsigned long tail_start ;
struct page * tail_page ;
struct page * hole_page = bh_result->b_page ;
int retval = 0 ;
if ((tail_offset & (bh_result->b_size - 1)) != 1)
return -EIO ;
/* always try to read until the end of the block */
tail_start = tail_offset & (PAGE_CACHE_SIZE - 1) ;
tail_end = (tail_start | (bh_result->b_size - 1)) + 1 ;
index = tail_offset >> PAGE_CACHE_SHIFT ;
if (index != hole_page->index) {
tail_page = grab_cache_page(inode->i_mapping, index) ;
retval = -ENOMEM;
if (!tail_page) {
goto out ;
}
} else {
tail_page = hole_page ;
}
/* we don't have to make sure the conversion did not happen while
** we were locking the page because anyone that could convert
** must first take i_sem.
**
** We must fix the tail page for writing because it might have buffers
** that are mapped, but have a block number of 0. This indicates tail
** data that has been read directly into the page, and block_prepare_write
** won't trigger a get_block in this case.
*/
fix_tail_page_for_writing(tail_page) ;
retval = block_prepare_write(tail_page, tail_start, tail_end,
reiserfs_get_block) ;
if (retval)
goto unlock ;
/* tail conversion might change the data in the page */
flush_dcache_page(tail_page) ;
retval = generic_commit_write(NULL, tail_page, tail_start, tail_end) ;
unlock:
if (tail_page != hole_page) {
UnlockPage(tail_page) ;
page_cache_release(tail_page) ;
}
out:
return retval ;
}
//
// initially this function was derived from ext2's analog and evolved
// as the prototype did. You'll need to look at the ext2 version to
// determine which parts are derivative, if any, understanding that
// there are only so many ways to code to a given interface.
//
int reiserfs_get_block (struct inode * inode, long block,
struct buffer_head * bh_result, int create)
{
int repeat, retval;
unsigned long tag;
b_blocknr_t allocated_block_nr = 0;// b_blocknr_t is unsigned long
INITIALIZE_PATH(path);
int pos_in_item;
struct cpu_key key;
struct buffer_head * bh, * unbh = 0;
struct item_head * ih, tmp_ih;
__u32 * item;
int done;
int fs_gen;
int windex ;
struct reiserfs_transaction_handle th ;
int jbegin_count = JOURNAL_PER_BALANCE_CNT * 3 ;
int version;
int transaction_started = 0 ;
loff_t new_offset = (block << inode->i_sb->s_blocksize_bits) + 1 ;
/* bad.... */
lock_kernel() ;
th.t_trans_id = 0 ;
version = inode_items_version (inode);
if (!file_capable (inode, block)) {
unlock_kernel() ;
return -EFBIG;
}
/* if !create, we aren't changing the FS, so we don't need to
** log anything, so we don't need to start a transaction
*/
if (!(create & GET_BLOCK_CREATE)) {
int ret ;
/* find number of block-th logical block of the file */
ret = _get_block_create_0 (inode, block, bh_result,
create | GET_BLOCK_READ_DIRECT) ;
unlock_kernel() ;
return ret;
}
if (block < 0) {
unlock_kernel();
return -EIO;
}
prevent_flush_page_lock(bh_result->b_page, inode) ;
inode->u.reiserfs_i.i_pack_on_close = 1 ;
windex = push_journal_writer("reiserfs_get_block") ;
/* set the key of the first byte in the 'block'-th block of file */
make_cpu_key (&key, inode,
(loff_t)block * inode->i_sb->s_blocksize + 1, // k_offset
TYPE_ANY, 3/*key length*/);
if ((new_offset + inode->i_sb->s_blocksize) >= inode->i_size) {
journal_begin(&th, inode->i_sb, jbegin_count) ;
transaction_started = 1 ;
}
research:
retval = search_for_position_by_key (inode->i_sb, &key, &path);
if (retval == IO_ERROR) {
retval = -EIO;
goto failure;
}
bh = get_bh (&path);
ih = get_ih (&path);
item = get_item (&path);
pos_in_item = path.pos_in_item;
fs_gen = get_generation (inode->i_sb);
copy_item_head (&tmp_ih, ih);
if (allocation_needed (retval, allocated_block_nr, ih, item, pos_in_item)) {
/* we have to allocate block for the unformatted node */
tag = find_tag (bh, ih, item, pos_in_item);
if (!transaction_started) {
pathrelse(&path) ;
journal_begin(&th, inode->i_sb, jbegin_count) ;
transaction_started = 1 ;
goto research ;
}
#ifdef REISERFS_PREALLOCATE
repeat = reiserfs_new_unf_blocknrs2 (&th, inode, &allocated_block_nr, tag);
#else
repeat = reiserfs_new_unf_blocknrs (&th, &allocated_block_nr, tag);
#endif
if (repeat == NO_DISK_SPACE) {
/* restart the transaction to give the journal a chance to free
** some blocks. releases the path, so we have to go back to
** research if we succeed on the second try
*/
restart_transaction(&th, inode, &path) ;
#ifdef REISERFS_PREALLOCATE
repeat = reiserfs_new_unf_blocknrs2 (&th, inode, &allocated_block_nr, tag);
#else
repeat = reiserfs_new_unf_blocknrs (&th, &allocated_block_nr, tag);
#endif
if (repeat != NO_DISK_SPACE) {
goto research ;
}
retval = -ENOSPC;
goto failure;
}
if (fs_changed (fs_gen, inode->i_sb) && item_moved (&tmp_ih, &path)) {
goto research;
}
}
if (indirect_item_found (retval, ih)) {
/* 'block'-th block is in the file already (there is
corresponding cell in some indirect item). But it may be
zero unformatted node pointer (hole) */
if (!item[pos_in_item]) {
/* use allocated block to plug the hole */
reiserfs_prepare_for_journal(inode->i_sb, bh, 1) ;
if (fs_changed (fs_gen, inode->i_sb) && item_moved (&tmp_ih, &path)) {
reiserfs_restore_prepared_buffer(inode->i_sb, bh) ;
goto research;
}
bh_result->b_state |= (1UL << BH_New);
item[pos_in_item] = cpu_to_le32 (allocated_block_nr);
journal_mark_dirty (&th, inode->i_sb, bh);
inode->i_blocks += (inode->i_sb->s_blocksize / 512) ;
reiserfs_update_sd(&th, inode) ;
}
set_block_dev_mapped(bh_result, le32_to_cpu (item[pos_in_item]), inode);
pathrelse (&path);
#ifdef REISERFS_CHECK
pop_journal_writer(windex) ;
#endif /* REISERFS_CHECK */
if (transaction_started)
journal_end(&th, inode->i_sb, jbegin_count) ;
allow_flush_page_lock(bh_result->b_page, inode) ;
unlock_kernel() ;
/* the item was found, so new blocks were not added to the file
** there is no need to make sure the inode is updated with this
** transaction
*/
return 0;
}
if (!transaction_started) {
/* if we don't pathrelse, we could vs-3050 on the buffer if
** someone is waiting for it (they can't finish until the buffer
** is released, we can start a new transaction until they finish)
*/
pathrelse(&path) ;
journal_begin(&th, inode->i_sb, jbegin_count) ;
transaction_started = 1 ;
goto research;
}
/* desired position is not found or is in the direct item. We have
to append file with holes up to 'block'-th block converting
direct items to indirect one if necessary */
done = 0;
do {
if (is_statdata_le_ih (ih)) {
__u32 unp = 0;
struct cpu_key tmp_key;
/* indirect item has to be inserted */
make_le_item_head (&tmp_ih, &key, version, 1, TYPE_INDIRECT,
UNFM_P_SIZE, 0/* free_space */);
if (cpu_key_k_offset (&key) == 1) {
/* we are going to add 'block'-th block to the file. Use
allocated block for that */
unp = cpu_to_le32 (allocated_block_nr);
set_block_dev_mapped (bh_result, allocated_block_nr, inode);
bh_result->b_state |= (1UL << BH_New);
done = 1;
}
tmp_key = key; // ;)
set_cpu_key_k_offset (&tmp_key, 1);
PATH_LAST_POSITION(&path) ++;
retval = reiserfs_insert_item (&th, &path, &tmp_key, &tmp_ih, (char *)&unp);
if (retval) {
reiserfs_free_block (&th, allocated_block_nr);
#ifdef REISERFS_PREALLOCATE
reiserfs_discard_prealloc (&th, inode);
#endif
goto failure; // retval == -ENOSPC or -EIO or -EEXIST
}
if (unp)
inode->i_blocks += inode->i_sb->s_blocksize / 512;
//mark_tail_converted (inode);
} else if (is_direct_le_ih (ih)) {
/* direct item has to be converted */
loff_t tail_offset;
tail_offset = ((le_ih_k_offset (ih) - 1) & ~(inode->i_sb->s_blocksize - 1)) + 1;
if (tail_offset == cpu_key_k_offset (&key)) {
/* direct item we just found fits into block we have
to map. Convert it into unformatted node: use
bh_result for the conversion */
set_block_dev_mapped (bh_result, allocated_block_nr, inode);
unbh = bh_result;
done = 1;
} else {
/* we have to padd file tail stored in direct item(s)
up to block size and convert it to unformatted
node. FIXME: this should also get into page cache */
pathrelse(&path) ;
journal_end(&th, inode->i_sb, jbegin_count) ;
transaction_started = 0 ;
retval = convert_tail_for_hole(inode, bh_result, tail_offset) ;
if (retval) {
printk("clm-6004: convert tail failed inode %lu, error %d\n", inode->i_ino, retval) ;
if (allocated_block_nr)
reiserfs_free_block (&th, allocated_block_nr);
goto failure ;
}
goto research ;
}
retval = direct2indirect (&th, inode, &path, unbh, tail_offset);
/* it is important the mark_buffer_uptodate is done after
** the direct2indirect. The buffer might contain valid
** data newer than the data on disk (read by readpage, changed,
** and then sent here by writepage). direct2indirect needs
** to know if unbh was already up to date, so it can decide
** if the data in unbh needs to be replaced with data from
** the disk
*/
mark_buffer_uptodate (unbh, 1);
if (retval) {
reiserfs_free_block (&th, allocated_block_nr);
#ifdef REISERFS_PREALLOCATE
reiserfs_discard_prealloc (&th, inode);
#endif
goto failure;
}
/* we've converted the tail, so we must
** flush unbh before the transaction commits
*/
reiserfs_add_page_to_flush_list(&th, inode, unbh) ;
mark_buffer_dirty(unbh) ;
//inode->i_blocks += inode->i_sb->s_blocksize / 512;
//mark_tail_converted (inode);
} else {
/* append indirect item with holes if needed, when appending
pointer to 'block'-th block use block, which is already
allocated */
struct cpu_key tmp_key;
struct unfm_nodeinfo un = {0, 0};
#ifdef CONFIG_REISERFS_CHECK
if (pos_in_item != le16_to_cpu (ih->ih_item_len) / UNFM_P_SIZE)
reiserfs_panic (inode->i_sb, "vs-: reiserfs_get_block: "
"invalid position for append");
#endif
/* indirect item has to be appended, set up key of that position */
make_cpu_key (&tmp_key, inode,
le_key_k_offset (version, &(ih->ih_key)) + op_bytes_number (ih, inode->i_sb->s_blocksize),
//pos_in_item * inode->i_sb->s_blocksize,
TYPE_INDIRECT, 3);// key type is unimportant
if (cpu_key_k_offset (&tmp_key) == cpu_key_k_offset (&key)) {
/* we are going to add target block to the file. Use allocated
block for that */
un.unfm_nodenum = cpu_to_le32 (allocated_block_nr);
set_block_dev_mapped (bh_result, allocated_block_nr, inode);
bh_result->b_state |= (1UL << BH_New);
done = 1;
} else {
/* paste hole to the indirect item */
}
retval = reiserfs_paste_into_item (&th, &path, &tmp_key, (char *)&un, UNFM_P_SIZE);
if (retval) {
reiserfs_free_block (&th, allocated_block_nr);
#ifdef REISERFS_PREALLOCATE
reiserfs_discard_prealloc (&th, inode);
#endif
goto failure;
}
if (un.unfm_nodenum)
inode->i_blocks += inode->i_sb->s_blocksize / 512;
//mark_tail_converted (inode);
}
if (done == 1)
break;
/* this loop could log more blocks than we had originally asked
** for. So, we have to allow the transaction to end if it is
** too big or too full. Update the inode so things are
** consistent if we crash before the function returns
**
** release the path so that anybody waiting on the path before
** ending their transaction will be able to continue.
*/
if (journal_transaction_should_end(&th, th.t_blocks_allocated)) {
restart_transaction(&th, inode, &path) ;
}
/* inserting indirect pointers for a hole can take a
** long time. reschedule if needed
*/
if (current->need_resched)
schedule() ;
retval = search_for_position_by_key (inode->i_sb, &key, &path);
if (retval == IO_ERROR) {
retval = -EIO;
goto failure;
}
if (retval == POSITION_FOUND) {
reiserfs_warning ("vs-: reiserfs_get_block: "
"%k should not be found", &key);
retval = -EEXIST;
pathrelse(&path) ;
goto failure;
}
bh = get_bh (&path);
ih = get_ih (&path);
item = get_item (&path);
pos_in_item = path.pos_in_item;
} while (1);
retval = 0;
reiserfs_check_path(&path) ;
failure:
if (transaction_started) {
reiserfs_update_sd(&th, inode) ;
journal_end(&th, inode->i_sb, jbegin_count) ;
}
pop_journal_writer(windex) ;
allow_flush_page_lock(bh_result->b_page, inode) ;
unlock_kernel() ;
reiserfs_check_path(&path) ;
return retval;
}
//
// BAD: new directories have stat data of new type and all other items
// of old type. Version stored in the inode says about body items, so
// in update_stat_data we can not rely on inode, but have to check
// item version directly
//
// called by read_inode
static void init_inode (struct inode * inode, struct path * path)
{
struct buffer_head * bh;
struct item_head * ih;
__u32 rdev;
//int version = ITEM_VERSION_1;
bh = PATH_PLAST_BUFFER (path);
ih = PATH_PITEM_HEAD (path);
copy_key (INODE_PKEY (inode), &(ih->ih_key));
inode->i_generation = INODE_PKEY (inode)->k_dir_id;
inode->i_blksize = PAGE_SIZE;
if (stat_data_v1 (ih)) {
struct stat_data_v1 * sd = (struct stat_data_v1 *)B_I_PITEM (bh, ih);
unsigned long blocks;
inode_items_version (inode) = ITEM_VERSION_1;
inode->i_mode = le16_to_cpu (sd->sd_mode);
inode->i_nlink = le16_to_cpu (sd->sd_nlink);
inode->i_uid = le16_to_cpu (sd->sd_uid);
inode->i_gid = le16_to_cpu (sd->sd_gid);
inode->i_size = le32_to_cpu (sd->sd_size);
inode->i_atime = le32_to_cpu (sd->sd_atime);
inode->i_mtime = le32_to_cpu (sd->sd_mtime);
inode->i_ctime = le32_to_cpu (sd->sd_ctime);
inode->i_blocks = le32_to_cpu (sd->u.sd_blocks);
blocks = (inode->i_size + 511) >> 9;
blocks = _ROUND_UP (blocks, inode->i_blksize >> 9);
if (inode->i_blocks > blocks) {
// there was a bug in <=3.5.23 when i_blocks could take negative
// values. Starting from 3.5.17 this value could even be stored in
// stat data. For such files we set i_blocks based on file
// size. Just 2 notes: this can be wrong for sparce files. On-disk value will be
// only updated if file's inode will ever change
inode->i_blocks = blocks;
}
rdev = le32_to_cpu (sd->u.sd_rdev);
inode->u.reiserfs_i.i_first_direct_byte = le32_to_cpu (sd->sd_first_direct_byte);
} else {
// new stat data found, but object may have old items
// (directories and symlinks)
struct stat_data * sd = (struct stat_data *)B_I_PITEM (bh, ih);
/* both old and new directories have old keys */
//version = (S_ISDIR (sd->sd_mode) ? ITEM_VERSION_1 : ITEM_VERSION_2);
if (S_ISDIR (sd->sd_mode) || S_ISLNK (sd->sd_mode))
inode_items_version (inode) = ITEM_VERSION_1;
else
inode_items_version (inode) = ITEM_VERSION_2;
inode->i_mode = le16_to_cpu (sd->sd_mode);
inode->i_nlink = le32_to_cpu (sd->sd_nlink);
inode->i_uid = le32_to_cpu (sd->sd_uid);
inode->i_size = le64_to_cpu (sd->sd_size);
inode->i_gid = le32_to_cpu (sd->sd_gid);
inode->i_mtime = le32_to_cpu (sd->sd_mtime);
inode->i_atime = le32_to_cpu (sd->sd_atime);
inode->i_ctime = le32_to_cpu (sd->sd_ctime);
inode->i_blocks = le32_to_cpu (sd->sd_blocks);
rdev = le32_to_cpu (sd->u.sd_rdev);
}
/* nopack = 0, by default */
inode->u.reiserfs_i.nopack = 0;
pathrelse (path);
if (S_ISREG (inode->i_mode)) {
inode->i_op = &reiserfs_file_inode_operations;
inode->i_fop = &reiserfs_file_operations;
inode->i_mapping->a_ops = &reiserfs_address_space_operations ;
} else if (S_ISDIR (inode->i_mode)) {
inode->i_op = &reiserfs_dir_inode_operations;
inode->i_fop = &reiserfs_dir_operations;
} else if (S_ISLNK (inode->i_mode)) {
inode->i_op = &page_symlink_inode_operations;
inode->i_mapping->a_ops = &reiserfs_address_space_operations;
} else {
inode->i_blocks = 0;
init_special_inode(inode, inode->i_mode, rdev) ;
}
}
// update new stat data with inode fields
static void inode2sd (void * sd, struct inode * inode)
{
struct stat_data * sd_v2 = (struct stat_data *)sd;
sd_v2->sd_mode = cpu_to_le16 (inode->i_mode);
sd_v2->sd_nlink = cpu_to_le16 (inode->i_nlink);
sd_v2->sd_uid = cpu_to_le32 (inode->i_uid);
sd_v2->sd_size = cpu_to_le64 (inode->i_size);
sd_v2->sd_gid = cpu_to_le32 (inode->i_gid);
sd_v2->sd_mtime = cpu_to_le32 (inode->i_mtime);
sd_v2->sd_atime = cpu_to_le32 (inode->i_atime);
sd_v2->sd_ctime = cpu_to_le32 (inode->i_ctime);
sd_v2->sd_blocks = cpu_to_le32 (inode->i_blocks);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
sd_v2->u.sd_rdev = cpu_to_le32 (inode->i_rdev);
}
// used to copy inode's fields to old stat data
static void inode2sd_v1 (void * sd, struct inode * inode)
{
struct stat_data_v1 * sd_v1 = (struct stat_data_v1 *)sd;
sd_v1->sd_mode = cpu_to_le16 (inode->i_mode);
sd_v1->sd_uid = cpu_to_le16 (inode->i_uid);
sd_v1->sd_gid = cpu_to_le16 (inode->i_gid);
sd_v1->sd_nlink = cpu_to_le16 (inode->i_nlink);
sd_v1->sd_size = cpu_to_le32 (inode->i_size);
sd_v1->sd_atime = cpu_to_le32 (inode->i_atime);
sd_v1->sd_ctime = cpu_to_le32 (inode->i_ctime);
sd_v1->sd_mtime = cpu_to_le32 (inode->i_mtime);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
sd_v1->u.sd_rdev = cpu_to_le32 (inode->i_rdev);
else
sd_v1->u.sd_blocks = cpu_to_le32 (inode->i_blocks);
// Sigh. i_first_direct_byte is back
sd_v1->sd_first_direct_byte = cpu_to_le32 (inode->u.reiserfs_i.i_first_direct_byte);
}
/* NOTE, you must prepare the buffer head before sending it here,
** and then log it after the call
*/
static void update_stat_data (struct path * path, struct inode * inode)
{
struct buffer_head * bh;
struct item_head * ih;
bh = PATH_PLAST_BUFFER (path);
ih = PATH_PITEM_HEAD (path);
if (!is_statdata_le_ih (ih))
reiserfs_panic (inode->i_sb, "vs-13065: update_stat_data: key %k, found item %h",
INODE_PKEY (inode), ih);
if (stat_data_v1 (ih)) {
// path points to old stat data
inode2sd_v1 (B_I_PITEM (bh, ih), inode);
} else {
inode2sd (B_I_PITEM (bh, ih), inode);
}
return;
}
void reiserfs_update_sd (struct reiserfs_transaction_handle *th,
struct inode * inode)
{
struct cpu_key key;
INITIALIZE_PATH(path);
struct buffer_head *bh ;
int fs_gen ;
struct item_head *ih, tmp_ih ;
int retval;
make_cpu_key (&key, inode, SD_OFFSET, TYPE_STAT_DATA, 3);//key type is unimportant
for(;;) {
int pos;
/* look for the object's stat data */
retval = search_item (inode->i_sb, &key, &path);
if (retval == IO_ERROR) {
reiserfs_warning ("vs-13050: reiserfs_update_sd: "
"i/o failure occurred trying to update %K stat data",
&key);
return;
}
if (retval == ITEM_NOT_FOUND) {
pos = PATH_LAST_POSITION (&path);
pathrelse(&path) ;
if (inode->i_nlink == 0) {
/*printk ("vs-13050: reiserfs_update_sd: i_nlink == 0, stat data not found\n");*/
return;
}
reiserfs_warning ("vs-13060: reiserfs_update_sd: "
"stat data of object %k (nlink == %d) not found (pos %d)\n",
INODE_PKEY (inode), inode->i_nlink, pos);
reiserfs_check_path(&path) ;
return;
}
/* sigh, prepare_for_journal might schedule. When it schedules the
** FS might change. We have to detect that, and loop back to the
** search if the stat data item has moved
*/
bh = get_bh(&path) ;
ih = get_ih(&path) ;
copy_item_head (&tmp_ih, ih);
fs_gen = get_generation (inode->i_sb);
reiserfs_prepare_for_journal(inode->i_sb, bh, 1) ;
if (fs_changed (fs_gen, inode->i_sb) && item_moved(&tmp_ih, &path)) {
reiserfs_restore_prepared_buffer(inode->i_sb, bh) ;
continue ; /* Stat_data item has been moved after scheduling. */
}
break;
}
update_stat_data (&path, inode);
journal_mark_dirty(th, th->t_super, bh) ;
pathrelse (&path);
return;
}
void reiserfs_read_inode(struct inode *inode) {
make_bad_inode(inode) ;
}
//
// initially this function was derived from minix or ext2's analog and
// evolved as the prototype did
//
/* looks for stat data in the tree, and fills up the fields of in-core
inode stat data fields */
void reiserfs_read_inode2 (struct inode * inode, void *p)
{
INITIALIZE_PATH (path_to_sd);
struct cpu_key key;
struct reiserfs_iget4_args *args = (struct reiserfs_iget4_args *)p ;
unsigned long dirino;
int retval;
if (!p) {
make_bad_inode(inode) ;
return;
}
dirino = args->objectid ;
/* set version 1, version 2 could be used too, because stat data
key is the same in both versions */
key.version = ITEM_VERSION_1;
key.on_disk_key.k_dir_id = dirino;
key.on_disk_key.k_objectid = inode->i_ino;
key.on_disk_key.u.k_offset_v1.k_offset = SD_OFFSET;
key.on_disk_key.u.k_offset_v1.k_uniqueness = SD_UNIQUENESS;
/* look for the object's stat data */
retval = search_item (inode->i_sb, &key, &path_to_sd);
if (retval == IO_ERROR) {
reiserfs_warning ("vs-13070: reiserfs_read_inode2: "
"i/o failure occurred trying to find stat data of %K\n",
&key);
make_bad_inode(inode) ;
return;
}
if (retval != ITEM_FOUND) {
reiserfs_warning ("vs-13042: reiserfs_read_inode2: %K not found\n", &key);
pathrelse (&path_to_sd);
make_bad_inode(inode) ;
return;
}
init_inode (inode, &path_to_sd);
reiserfs_check_path(&path_to_sd) ; /* init inode should be relsing */
}
struct inode * reiserfs_iget (struct super_block * s, struct cpu_key * key)
{
struct inode * inode;
struct reiserfs_iget4_args args ;
args.objectid = key->on_disk_key.k_dir_id ;
inode = iget4 (s, key->on_disk_key.k_objectid, 0, (void *)(&args));
if (!inode)
return inode ;
// if (comp_short_keys (INODE_PKEY (inode), key)) {
if (is_bad_inode (inode)) {
reiserfs_warning ("vs-13048: reiserfs_iget: "
"bad_inode. Stat data of (%lu %lu) not found\n",
key->on_disk_key.k_dir_id, key->on_disk_key.k_objectid);
iput (inode);
inode = 0;
}
return inode;
}
//
// initially this function was derived from minix or ext2's analog and
// evolved as the prototype did
//
/* looks for stat data, then copies fields to it, marks the buffer
containing stat data as dirty */
/* reiserfs inodes are never really dirty, since the dirty inode call
** always logs them. This call allows the VFS inode marking routines
** to properly mark inodes for datasync and such, but only actually
** does something when called for a synchronous update.
*/
void reiserfs_write_inode (struct inode * inode, int do_sync) {
struct reiserfs_transaction_handle th ;
int jbegin_count = 1 ;
if (inode->i_sb->s_flags & MS_RDONLY) {
reiserfs_warning("clm-6005: writing inode %lu on readonly FS\n",
inode->i_ino) ;
return ;
}
if (do_sync) {
lock_kernel() ;
journal_begin(&th, inode->i_sb, jbegin_count) ;
reiserfs_update_sd (&th, inode);
journal_end_sync(&th, inode->i_sb, jbegin_count) ;
unlock_kernel() ;
}
}
void reiserfs_dirty_inode (struct inode * inode) {
struct reiserfs_transaction_handle th ;
if (inode->i_sb->s_flags & MS_RDONLY) {
reiserfs_warning("clm-6006: writing inode %lu on readonly FS\n",
inode->i_ino) ;
return ;
}
lock_kernel() ;
journal_begin(&th, inode->i_sb, 1) ;
reiserfs_update_sd (&th, inode);
journal_end(&th, inode->i_sb, 1) ;
unlock_kernel() ;
}
/* FIXME: no need any more. right? */
int reiserfs_sync_inode (struct reiserfs_transaction_handle *th, struct inode * inode)
{
int err = 0;
reiserfs_update_sd (th, inode);
return err;
}
/* stat data of new object is inserted already, this inserts the item
containing "." and ".." entries */
static int reiserfs_new_directory (struct reiserfs_transaction_handle *th,
struct item_head * ih, struct path * path, const struct inode * dir)
{
struct super_block * sb = th->t_super;
char empty_dir [EMPTY_DIR_SIZE];
char * body = empty_dir;
struct cpu_key key;
int retval;
_make_cpu_key (&key, ITEM_VERSION_1, le32_to_cpu (ih->ih_key.k_dir_id),
le32_to_cpu (ih->ih_key.k_objectid), DOT_OFFSET, TYPE_DIRENTRY, 3/*key length*/);
/* compose item head for new item. Directories consist of items of
old type (ITEM_VERSION_1). Do not set key (second arg is 0), it
is done by reiserfs_new_inode */
if (old_format_only (sb)) {
make_le_item_head (ih, 0, ITEM_VERSION_1, DOT_OFFSET, TYPE_DIRENTRY, EMPTY_DIR_SIZE_V1, 2);
make_empty_dir_item_v1 (body, ih->ih_key.k_dir_id, ih->ih_key.k_objectid,
le32_to_cpu (INODE_PKEY (dir)->k_dir_id),
le32_to_cpu (INODE_PKEY (dir)->k_objectid));
} else {
make_le_item_head (ih, 0, ITEM_VERSION_1, DOT_OFFSET, TYPE_DIRENTRY, EMPTY_DIR_SIZE, 2);
make_empty_dir_item (body, ih->ih_key.k_dir_id, ih->ih_key.k_objectid,
le32_to_cpu (INODE_PKEY (dir)->k_dir_id),
le32_to_cpu (INODE_PKEY (dir)->k_objectid));
}
/* look for place in the tree for new item */
retval = search_item (sb, &key, path);
if (retval == IO_ERROR) {
reiserfs_warning ("vs-13080: reiserfs_new_directory: "
"i/o failure occurred creating new directory\n");
return -EIO;
}
if (retval == ITEM_FOUND) {
pathrelse (path);
reiserfs_warning ("vs-13070: reiserfs_new_directory: "
"object with this key exists (%k)", &(ih->ih_key));
return -EEXIST;
}
/* insert item, that is empty directory item */
return reiserfs_insert_item (th, path, &key, ih, body);
}
/* stat data of object has been inserted, this inserts the item
containing the body of symlink */
static int reiserfs_new_symlink (struct reiserfs_transaction_handle *th,
struct item_head * ih,
struct path * path, const char * symname, int item_len)
{
struct super_block * sb = th->t_super;
struct cpu_key key;
int retval;
_make_cpu_key (&key, ITEM_VERSION_1,
le32_to_cpu (ih->ih_key.k_dir_id),
le32_to_cpu (ih->ih_key.k_objectid),
1, TYPE_DIRECT, 3/*key length*/);
make_le_item_head (ih, 0, ITEM_VERSION_1, 1, TYPE_DIRECT, item_len, 0/*free_space*/);
/* look for place in the tree for new item */
retval = search_item (sb, &key, path);
if (retval == IO_ERROR) {
reiserfs_warning ("vs-13080: reiserfs_new_symlinik: "
"i/o failure occurred creating new symlink\n");
return -EIO;
}
if (retval == ITEM_FOUND) {
pathrelse (path);
reiserfs_warning ("vs-13080: reiserfs_new_symlink: "
"object with this key exists (%k)", &(ih->ih_key));
return -EEXIST;
}
/* insert item, that is body of symlink */
return reiserfs_insert_item (th, path, &key, ih, symname);
}
/* inserts the stat data into the tree, and then calls
reiserfs_new_directory (to insert ".", ".." item if new object is
directory) or reiserfs_new_symlink (to insert symlink body if new
object is symlink) or nothing (if new object is regular file) */
struct inode * reiserfs_new_inode (struct reiserfs_transaction_handle *th,
const struct inode * dir, int mode,
const char * symname,
int i_size, /* 0 for regular, EMTRY_DIR_SIZE for dirs,
strlen (symname) for symlinks)*/
struct dentry *dentry, struct inode *inode, int * err)
{
struct super_block * sb;
INITIALIZE_PATH (path_to_key);
struct cpu_key key;
struct item_head ih;
struct stat_data sd;
int retval;
if (!dir || !dir->i_nlink) {
*err = -EPERM;
iput(inode) ;
return NULL;
}
sb = dir->i_sb;
inode->i_sb = sb;
inode->i_flags = 0;//inode->i_sb->s_flags;
/* item head of new item */
ih.ih_key.k_dir_id = INODE_PKEY (dir)->k_objectid;
ih.ih_key.k_objectid = cpu_to_le32 (reiserfs_get_unused_objectid (th));
if (!ih.ih_key.k_objectid) {
iput(inode) ;
*err = -ENOMEM;
return NULL;
}
if (old_format_only (sb))
make_le_item_head (&ih, 0, ITEM_VERSION_1, SD_OFFSET, TYPE_STAT_DATA, SD_V1_SIZE, MAX_US_INT);
else
make_le_item_head (&ih, 0, ITEM_VERSION_2, SD_OFFSET, TYPE_STAT_DATA, SD_SIZE, MAX_US_INT);
/* key to search for correct place for new stat data */
_make_cpu_key (&key, ITEM_VERSION_2, le32_to_cpu (ih.ih_key.k_dir_id),
le32_to_cpu (ih.ih_key.k_objectid), SD_OFFSET, TYPE_STAT_DATA, 3/*key length*/);
/* find proper place for inserting of stat data */
retval = search_item (sb, &key, &path_to_key);
if (retval == IO_ERROR) {
iput (inode);
*err = -EIO;
return NULL;
}
if (retval == ITEM_FOUND) {
pathrelse (&path_to_key);
iput (inode);
*err = -EEXIST;
return NULL;
}
/* fill stat data */
inode->i_mode = mode;
inode->i_nlink = (S_ISDIR (mode) ? 2 : 1);
inode->i_uid = current->fsuid;
if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
inode->i_mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_size = i_size;
inode->i_blocks = (inode->i_size + 511) >> 9;
inode->u.reiserfs_i.i_first_direct_byte = S_ISLNK(mode) ? 1 :
U32_MAX/*NO_BYTES_IN_DIRECT_ITEM*/;
if (old_format_only (sb))
inode2sd_v1 (&sd, inode);
else
inode2sd (&sd, inode);
// these do not go to on-disk stat data
inode->i_ino = le32_to_cpu (ih.ih_key.k_objectid);
inode->i_blksize = PAGE_SIZE;
inode->i_dev = sb->s_dev;
// store in in-core inode the key of stat data and version all
// object items will have (directory items will have old offset
// format, other new objects will consist of new items)
memcpy (INODE_PKEY (inode), &(ih.ih_key), KEY_SIZE);
if (old_format_only (sb) || S_ISDIR(mode) || S_ISLNK(mode))
inode_items_version (inode) = ITEM_VERSION_1;
else
inode_items_version (inode) = ITEM_VERSION_2;
/* insert the stat data into the tree */
retval = reiserfs_insert_item (th, &path_to_key, &key, &ih, (char *)(&sd));
if (retval) {
iput (inode);
*err = retval;
reiserfs_check_path(&path_to_key) ;
return NULL;
}
if (S_ISDIR(mode)) {
/* insert item with "." and ".." */
retval = reiserfs_new_directory (th, &ih, &path_to_key, dir);
}
if (S_ISLNK(mode)) {
/* insert body of symlink */
if (!old_format_only (sb))
i_size = ROUND_UP(i_size);
retval = reiserfs_new_symlink (th, &ih, &path_to_key, symname, i_size);
}
if (retval) {
inode->i_nlink = 0;
iput (inode);
*err = retval;
reiserfs_check_path(&path_to_key) ;
return NULL;
}
/* not a perfect generation count, as object ids can be reused, but this
** is as good as reiserfs can do right now
*/
inode->i_generation = INODE_PKEY (inode)->k_dir_id;
insert_inode_hash (inode);
// we do not mark inode dirty: on disk content matches to the
// in-core one
reiserfs_check_path(&path_to_key) ;
return inode;
}
/*
** finds the tail page in the page cache,
** reads the last block in.
**
** On success, page_result is set to a locked, pinned page, and bh_result
** is set to an up to date buffer for the last block in the file. returns 0.
**
** tail conversion is not done, so bh_result might not be valid for writing
** check buffer_mapped(bh_result) and bh_result->b_blocknr != 0 before
** trying to write the block.
**
** on failure, nonzero is returned, page_result and bh_result are untouched.
*/
static int grab_tail_page(struct inode *p_s_inode,
struct page **page_result,
struct buffer_head **bh_result) {
/* we want the page with the last byte in the file,
** not the page that will hold the next byte for appending
*/
unsigned long index = (p_s_inode->i_size-1) >> PAGE_CACHE_SHIFT ;
unsigned long pos = 0 ;
unsigned long start = 0 ;
unsigned long blocksize = p_s_inode->i_sb->s_blocksize ;
unsigned long offset = (p_s_inode->i_size) & (PAGE_CACHE_SIZE - 1) ;
struct buffer_head *bh ;
struct buffer_head *head ;
struct page * page ;
int error ;
/* we know that we are only called with inode->i_size > 0.
** we also know that a file tail can never be as big as a block
** If i_size % blocksize == 0, our file is currently block aligned
** and it won't need converting or zeroing after a truncate.
*/
if ((offset & (blocksize - 1)) == 0) {
return -ENOENT ;
}
page = grab_cache_page(p_s_inode->i_mapping, index) ;
error = -ENOMEM ;
if (!page) {
goto out ;
}
/* start within the page of the last block in the file */
start = (offset / blocksize) * blocksize ;
error = block_prepare_write(page, start, offset,
reiserfs_get_block_create_0) ;
if (error)
goto unlock ;
kunmap(page) ; /* mapped by block_prepare_write */
head = page->buffers ;
bh = head;
do {
if (pos >= start) {
break ;
}
bh = bh->b_this_page ;
pos += blocksize ;
} while(bh != head) ;
if (!buffer_uptodate(bh)) {
/* note, this should never happen, prepare_write should
** be taking care of this for us. If the buffer isn't up to date,
** I've screwed up the code to find the buffer, or the code to
** call prepare_write
*/
reiserfs_warning("clm-6000: error reading block %lu on dev %s\n",
bh->b_blocknr, kdevname(bh->b_dev)) ;
error = -EIO ;
goto unlock ;
}
*bh_result = bh ;
*page_result = page ;
out:
return error ;
unlock:
UnlockPage(page) ;
page_cache_release(page) ;
return error ;
}
/*
** vfs version of truncate file. Must NOT be called with
** a transaction already started.
**
** some code taken from block_truncate_page
*/
void reiserfs_truncate_file(struct inode *p_s_inode, int update_timestamps) {
struct reiserfs_transaction_handle th ;
int windex ;
/* we want the offset for the first byte after the end of the file */
unsigned long offset = p_s_inode->i_size & (PAGE_CACHE_SIZE - 1) ;
unsigned blocksize = p_s_inode->i_sb->s_blocksize ;
unsigned length ;
struct page *page = NULL ;
int error ;
struct buffer_head *bh = NULL ;
if (p_s_inode->i_size > 0) {
if ((error = grab_tail_page(p_s_inode, &page, &bh))) {
// -ENOENT means we truncated past the end of the file,
// and get_block_create_0 could not find a block to read in,
// which is ok.
if (error != -ENOENT)
reiserfs_warning("clm-6001: grab_tail_page failed %d\n", error);
page = NULL ;
bh = NULL ;
}
}
/* so, if page != NULL, we have a buffer head for the offset at
** the end of the file. if the bh is mapped, and bh->b_blocknr != 0,
** then we have an unformatted node. Otherwise, we have a direct item,
** and no zeroing is required on disk. We zero after the truncate,
** because the truncate might pack the item anyway
** (it will unmap bh if it packs).
*/
prevent_flush_page_lock(page, p_s_inode) ;
journal_begin(&th, p_s_inode->i_sb, JOURNAL_PER_BALANCE_CNT * 2 ) ;
windex = push_journal_writer("reiserfs_vfs_truncate_file") ;
reiserfs_do_truncate (&th, p_s_inode, page, update_timestamps) ;
pop_journal_writer(windex) ;
journal_end(&th, p_s_inode->i_sb, JOURNAL_PER_BALANCE_CNT * 2 ) ;
allow_flush_page_lock(page, p_s_inode) ;
if (page) {
length = offset & (blocksize - 1) ;
/* if we are not on a block boundary */
if (length) {
length = blocksize - length ;
memset((char *)kmap(page) + offset, 0, length) ;
flush_dcache_page(page) ;
kunmap(page) ;
if (buffer_mapped(bh) && bh->b_blocknr != 0) {
mark_buffer_dirty(bh) ;
}
}
UnlockPage(page) ;
page_cache_release(page) ;
}
return ;
}
static int map_block_for_writepage(struct inode *inode,
struct buffer_head *bh_result,
unsigned long block) {
struct reiserfs_transaction_handle th ;
int fs_gen ;
struct item_head tmp_ih ;
struct item_head *ih ;
struct buffer_head *bh ;
__u32 *item ;
struct cpu_key key ;
INITIALIZE_PATH(path) ;
int pos_in_item ;
int jbegin_count = JOURNAL_PER_BALANCE_CNT ;
loff_t byte_offset = (block << inode->i_sb->s_blocksize_bits) + 1 ;
int retval ;
int use_get_block = 0 ;
int bytes_copied = 0 ;
int copy_size ;
start_over:
lock_kernel() ;
prevent_flush_page_lock(bh_result->b_page, inode) ;
journal_begin(&th, inode->i_sb, jbegin_count) ;
make_cpu_key(&key, inode, byte_offset, TYPE_ANY, 3) ;
research:
retval = search_for_position_by_key(inode->i_sb, &key, &path) ;
if (retval != POSITION_FOUND) {
use_get_block = 1;
goto out ;
}
bh = get_bh(&path) ;
ih = get_ih(&path) ;
item = get_item(&path) ;
pos_in_item = path.pos_in_item ;
/* we've found an unformatted node */
if (indirect_item_found(retval, ih)) {
if (bytes_copied > 0) {
reiserfs_warning("clm-6002: bytes_copied %d\n", bytes_copied) ;
}
if (!item[pos_in_item]) {
/* crap, we are writing to a hole */
use_get_block = 1;
goto out ;
}
set_block_dev_mapped(bh_result, le32_to_cpu(item[pos_in_item]), inode);
mark_buffer_uptodate(bh_result, 1);
} else if (is_direct_le_ih(ih)) {
char *p ;
p = page_address(bh_result->b_page) ;
p += (byte_offset -1) & (PAGE_CACHE_SIZE - 1) ;
copy_size = le16_to_cpu(ih->ih_item_len) - pos_in_item ;
fs_gen = get_generation(inode->i_sb) ;
copy_item_head(&tmp_ih, ih) ;
reiserfs_prepare_for_journal(inode->i_sb, bh, 1) ;
if (fs_changed (fs_gen, inode->i_sb) && item_moved (&tmp_ih, &path)) {
reiserfs_restore_prepared_buffer(inode->i_sb, bh) ;
goto research;
}
memcpy( B_I_PITEM(bh, ih) + pos_in_item, p + bytes_copied, copy_size) ;
journal_mark_dirty(&th, inode->i_sb, bh) ;
bytes_copied += copy_size ;
set_block_dev_mapped(bh_result, 0, inode);
mark_buffer_uptodate(bh_result, 1);
/* are there still bytes left? */
if (bytes_copied < bh_result->b_size &&
(byte_offset + bytes_copied) < inode->i_size) {
set_cpu_key_k_offset(&key, cpu_key_k_offset(&key) + copy_size) ;
goto research ;
}
} else {
reiserfs_warning("clm-6003: bad item inode %lu, device %s\n", inode->i_ino, kdevname(inode->i_sb->s_dev)) ;
retval = -EIO ;
goto out ;
}
retval = 0 ;
out:
pathrelse(&path) ;
journal_end(&th, inode->i_sb, jbegin_count) ;
allow_flush_page_lock(bh_result->b_page, inode) ;
unlock_kernel() ;
/* this is where we fill in holes in the file. */
if (use_get_block) {
kmap(bh_result->b_page) ;
retval = reiserfs_get_block(inode, block, bh_result, 1) ;
kunmap(bh_result->b_page) ;
if (!retval) {
if (!buffer_mapped(bh_result) || bh_result->b_blocknr == 0) {
/* get_block failed to find a mapped unformatted node. */
use_get_block = 0 ;
goto start_over ;
}
}
}
return retval ;
}
/* helper func to get a buffer head ready for writepage to send to
** ll_rw_block
*/
static inline void submit_bh_for_writepage(struct buffer_head **bhp, int nr) {
struct buffer_head *bh ;
int i;
for(i = 0 ; i < nr ; i++) {
bh = bhp[i] ;
lock_buffer(bh) ;
atomic_inc(&bh->b_count) ; /* async end_io handler decs this */
set_buffer_async_io(bh) ;
/* submit_bh doesn't care if the buffer is dirty, but nobody
** later on in the call chain will be cleaning it. So, we
** clean the buffer here, it still gets written either way.
*/
clear_bit(BH_Dirty, &bh->b_state) ;
set_bit(BH_Uptodate, &bh->b_state) ;
submit_bh(WRITE, bh) ;
}
}
static int reiserfs_write_full_page(struct page *page) {
struct inode *inode = page->mapping->host ;
unsigned long end_index = inode->i_size >> PAGE_CACHE_SHIFT ;
unsigned last_offset = PAGE_CACHE_SIZE;
int error = 0;
unsigned long block ;
unsigned cur_offset = 0 ;
struct buffer_head *head, *bh ;
int partial = 0 ;
struct buffer_head *arr[PAGE_CACHE_SIZE/512] ;
int nr = 0 ;
if (!page->buffers) {
block_prepare_write(page, 0, 0, NULL) ;
kunmap(page) ;
}
/* last page in the file, zero out any contents past the
** last byte in the file
*/
if (page->index >= end_index) {
last_offset = inode->i_size & (PAGE_CACHE_SIZE - 1) ;
/* no file contents in this page */
if (page->index >= end_index + 1 || !last_offset) {
error = -EIO ;
goto fail ;
}
memset((char *)kmap(page)+last_offset, 0, PAGE_CACHE_SIZE-last_offset) ;
flush_dcache_page(page) ;
kunmap(page) ;
}
head = page->buffers ;
bh = head ;
block = page->index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits) ;
do {
/* if this offset in the page is outside the file */
if (cur_offset >= last_offset) {
if (!buffer_uptodate(bh))
partial = 1 ;
} else {
/* fast path, buffer mapped to an unformatted node */
if (buffer_mapped(bh) && bh->b_blocknr != 0) {
arr[nr++] = bh ;
} else {
/* buffer not mapped yet, or points to a direct item.
** search and dirty or log
*/
if ((error = map_block_for_writepage(inode, bh, block))) {
goto fail ;
}
/* map_block_for_writepage either found an unformatted node
** and mapped it for us, or it found a direct item
** and logged the changes.
*/
if (buffer_mapped(bh) && bh->b_blocknr != 0) {
arr[nr++] = bh ;
}
}
}
bh = bh->b_this_page ;
cur_offset += bh->b_size ;
block++ ;
} while(bh != head) ;
/* if this page only had a direct item, it is very possible for
** nr == 0 without there being any kind of error.
*/
if (nr) {
submit_bh_for_writepage(arr, nr) ;
} else {
UnlockPage(page) ;
}
if (!partial)
SetPageUptodate(page) ;
return 0 ;
fail:
if (nr) {
submit_bh_for_writepage(arr, nr) ;
} else {
UnlockPage(page) ;
}
ClearPageUptodate(page) ;
return error ;
}
//
// this is exactly what 2.3.99-pre9's ext2_readpage is
//
static int reiserfs_readpage (struct file *f, struct page * page)
{
return block_read_full_page (page, reiserfs_get_block);
}
//
// modified from ext2_writepage is
//
static int reiserfs_writepage (struct page * page)
{
struct inode *inode = page->mapping->host ;
reiserfs_wait_on_write_block(inode->i_sb) ;
return reiserfs_write_full_page(page) ;
}
//
// from ext2_prepare_write, but modified
//
int reiserfs_prepare_write(struct file *f, struct page *page, unsigned from, unsigned to) {
struct inode *inode = page->mapping->host ;
reiserfs_wait_on_write_block(inode->i_sb) ;
fix_tail_page_for_writing(page) ;
return block_prepare_write(page, from, to, reiserfs_get_block) ;
}
//
// this is exactly what 2.3.99-pre9's ext2_bmap is
//
static int reiserfs_aop_bmap(struct address_space *as, long block) {
return generic_block_bmap(as, block, reiserfs_bmap) ;
}
static int reiserfs_commit_write(struct file *f, struct page *page,
unsigned from, unsigned to) {
struct inode *inode = page->mapping->host ;
int ret ;
struct reiserfs_transaction_handle th ;
reiserfs_wait_on_write_block(inode->i_sb) ;
lock_kernel();
prevent_flush_page_lock(page, inode) ;
ret = generic_commit_write(f, page, from, to) ;
/* we test for O_SYNC here so we can commit the transaction
** for any packed tails the file might have had
*/
if (f->f_flags & O_SYNC) {
journal_begin(&th, inode->i_sb, 1) ;
reiserfs_prepare_for_journal(inode->i_sb,
SB_BUFFER_WITH_SB(inode->i_sb), 1) ;
journal_mark_dirty(&th, inode->i_sb, SB_BUFFER_WITH_SB(inode->i_sb)) ;
journal_end_sync(&th, inode->i_sb, 1) ;
}
allow_flush_page_lock(page, inode) ;
unlock_kernel();
return ret ;
}
struct address_space_operations reiserfs_address_space_operations = {
writepage: reiserfs_writepage,
readpage: reiserfs_readpage,
sync_page: block_sync_page,
prepare_write: reiserfs_prepare_write,
commit_write: reiserfs_commit_write,
bmap: reiserfs_aop_bmap
} ;
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