// comment? maybe something like set de to point to what the path points to?
static inline void set_de_item_location (struct reiserfs_dir_entry * de, struct path * path)
{
de->de_bh = get_last_bh (path);
de->de_ih = get_ih (path);
de->de_deh = B_I_DEH (de->de_bh, de->de_ih);
de->de_item_num = PATH_LAST_POSITION (path);
}
/* returns 1 if it finds an indirect item and gets valid hint info
* from it, otherwise 0
*/
static int get_left_neighbor(reiserfs_blocknr_hint_t *hint)
{
struct path * path;
struct buffer_head * bh;
struct item_head * ih;
int pos_in_item;
__u32 * item;
int ret = 0;
if (!hint->path) /* reiserfs code can call this function w/o pointer to path
* structure supplied; then we rely on supplied search_start */
return 0;
path = hint->path;
bh = get_last_bh(path);
RFALSE( !bh, "green-4002: Illegal path specified to get_left_neighbor");
ih = get_ih(path);
pos_in_item = path->pos_in_item;
item = get_item (path);
hint->search_start = bh->b_blocknr;
if (!hint->formatted_node && is_indirect_le_ih (ih)) {
/* 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--;
// pos_in_item = I_UNFM_NUM (ih) - 1;
while (pos_in_item >= 0) {
int t=get_block_num(item,pos_in_item);
if (t) {
hint->search_start = t;
ret = 1;
break;
}
pos_in_item --;
}
}
/* does result value fit into specified region? */
return ret;
}
/* Allocates blocks for a file to fulfil write request.
Maps all unmapped but prepared pages from the list.
Updates metadata with newly allocated blocknumbers as needed */
int reiserfs_allocate_blocks_for_region(
struct reiserfs_transaction_handle *th,
struct inode *inode, /* Inode we work with */
loff_t pos, /* Writing position */
int num_pages, /* number of pages write going
to touch */
int write_bytes, /* amount of bytes to write */
struct page **prepared_pages, /* array of
prepared pages
*/
int blocks_to_allocate /* Amount of blocks we
need to allocate to
fit the data into file
*/
)
{
struct cpu_key key; // cpu key of item that we are going to deal with
struct item_head *ih; // pointer to item head that we are going to deal with
struct buffer_head *bh; // Buffer head that contains items that we are going to deal with
__u32 * item; // pointer to item we are going to deal with
INITIALIZE_PATH(path); // path to item, that we are going to deal with.
b_blocknr_t *allocated_blocks; // Pointer to a place where allocated blocknumbers would be stored.
reiserfs_blocknr_hint_t hint; // hint structure for block allocator.
size_t res; // return value of various functions that we call.
int curr_block; // current block used to keep track of unmapped blocks.
int i; // loop counter
int itempos; // position in item
unsigned int from = (pos & (PAGE_CACHE_SIZE - 1)); // writing position in
// first page
unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; /* last modified byte offset in last page */
__u64 hole_size ; // amount of blocks for a file hole, if it needed to be created.
int modifying_this_item = 0; // Flag for items traversal code to keep track
// of the fact that we already prepared
// current block for journal
int will_prealloc = 0;
RFALSE(!blocks_to_allocate, "green-9004: tried to allocate zero blocks?");
/* only preallocate if this is a small write */
if (REISERFS_I(inode)->i_prealloc_count ||
(!(write_bytes & (inode->i_sb->s_blocksize -1)) &&
blocks_to_allocate <
REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize))
will_prealloc = REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize;
allocated_blocks = kmalloc((blocks_to_allocate + will_prealloc) *
sizeof(b_blocknr_t), GFP_NOFS);
/* First we compose a key to point at the writing position, we want to do
that outside of any locking region. */
make_cpu_key (&key, inode, pos+1, TYPE_ANY, 3/*key length*/);
/* If we came here, it means we absolutely need to open a transaction,
since we need to allocate some blocks */
reiserfs_write_lock(inode->i_sb); // Journaling stuff and we need that.
journal_begin(th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1); // Wish I know if this number enough
reiserfs_update_inode_transaction(inode) ;
/* Look for the in-tree position of our write, need path for block allocator */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit;
}
/* Allocate blocks */
/* First fill in "hint" structure for block allocator */
hint.th = th; // transaction handle.
hint.path = &path; // Path, so that block allocator can determine packing locality or whatever it needs to determine.
hint.inode = inode; // Inode is needed by block allocator too.
hint.search_start = 0; // We have no hint on where to search free blocks for block allocator.
hint.key = key.on_disk_key; // on disk key of file.
hint.block = inode->i_blocks>>(inode->i_sb->s_blocksize_bits-9); // Number of disk blocks this file occupies already.
hint.formatted_node = 0; // We are allocating blocks for unformatted node.
hint.preallocate = will_prealloc;
/* Call block allocator to allocate blocks */
res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate);
if ( res != CARRY_ON ) {
if ( res == NO_DISK_SPACE ) {
/* We flush the transaction in case of no space. This way some
blocks might become free */
SB_JOURNAL(inode->i_sb)->j_must_wait = 1;
restart_transaction(th, inode, &path);
/* We might have scheduled, so search again */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit;
}
/* update changed info for hint structure. */
res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate);
if ( res != CARRY_ON ) {
res = -ENOSPC;
pathrelse(&path);
goto error_exit;
}
} else {
res = -ENOSPC;
pathrelse(&path);
goto error_exit;
}
}
#ifdef __BIG_ENDIAN
// Too bad, I have not found any way to convert a given region from
// cpu format to little endian format
{
int i;
for ( i = 0; i < blocks_to_allocate ; i++)
allocated_blocks[i]=cpu_to_le32(allocated_blocks[i]);
}
#endif
/* Blocks allocating well might have scheduled and tree might have changed,
let's search the tree again */
/* find where in the tree our write should go */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit_free_blocks;
}
bh = get_last_bh( &path ); // Get a bufferhead for last element in path.
ih = get_ih( &path ); // Get a pointer to last item head in path.
item = get_item( &path ); // Get a pointer to last item in path
/* Let's see what we have found */
if ( res != POSITION_FOUND ) { /* position not found, this means that we
might need to append file with holes
first */
// Since we are writing past the file's end, we need to find out if
// there is a hole that needs to be inserted before our writing
// position, and how many blocks it is going to cover (we need to
// populate pointers to file blocks representing the hole with zeros)
{
int item_offset = 1;
/*
* if ih is stat data, its offset is 0 and we don't want to
* add 1 to pos in the hole_size calculation
*/
if (is_statdata_le_ih(ih))
item_offset = 0;
hole_size = (pos + item_offset -
(le_key_k_offset( get_inode_item_key_version(inode),
&(ih->ih_key)) +
op_bytes_number(ih, inode->i_sb->s_blocksize))) >>
inode->i_sb->s_blocksize_bits;
}
/* look for uncompleted unlinks and truncates and complete them */
static void finish_unfinished (struct super_block * s)
{
INITIALIZE_PATH (path);
struct cpu_key max_cpu_key, obj_key;
struct key save_link_key;
int retval;
struct item_head * ih;
struct buffer_head * bh;
int item_pos;
char * item;
int done;
struct inode * inode;
int truncate;
/* compose key to look for "save" links */
max_cpu_key.version = KEY_FORMAT_3_5;
max_cpu_key.on_disk_key = MAX_KEY;
max_cpu_key.key_length = 3;
done = 0;
s -> u.reiserfs_sb.s_is_unlinked_ok = 1;
while (1) {
retval = search_item (s, &max_cpu_key, &path);
if (retval != ITEM_NOT_FOUND) {
reiserfs_warning ("vs-2140: finish_unfinished: search_by_key returned %d\n",
retval);
break;
}
bh = get_last_bh (&path);
item_pos = get_item_pos (&path);
if (item_pos != B_NR_ITEMS (bh)) {
reiserfs_warning ("vs-2060: finish_unfinished: wrong position found\n");
break;
}
item_pos --;
ih = B_N_PITEM_HEAD (bh, item_pos);
if (le32_to_cpu (ih->ih_key.k_dir_id) != MAX_KEY_OBJECTID)
/* there are no "save" links anymore */
break;
save_link_key = ih->ih_key;
if (is_indirect_le_ih (ih))
truncate = 1;
else
truncate = 0;
/* reiserfs_iget needs k_dirid and k_objectid only */
item = B_I_PITEM (bh, ih);
obj_key.on_disk_key.k_dir_id = le32_to_cpu (*(__u32 *)item);
obj_key.on_disk_key.k_objectid = le32_to_cpu (ih->ih_key.k_objectid);
obj_key.on_disk_key.u.k_offset_v1.k_offset = 0;
obj_key.on_disk_key.u.k_offset_v1.k_uniqueness = 0;
pathrelse (&path);
inode = reiserfs_iget (s, &obj_key);
if (!inode) {
/* the unlink almost completed, it just did not manage to remove
"save" link and release objectid */
reiserfs_warning ("vs-2180: finish_unfinished: iget failed for %K\n",
&obj_key);
remove_save_link_only (s, &save_link_key, 1);
continue;
}
if (!truncate && inode->i_nlink) {
/* file is not unlinked */
reiserfs_warning ("vs-2185: finish_unfinished: file %K is not unlinked\n",
&obj_key);
remove_save_link_only (s, &save_link_key, 0);
continue;
}
if (truncate && S_ISDIR (inode->i_mode) ) {
/* We got a truncate request for a dir which is impossible.
The only imaginable way is to execute unfinished truncate request
then boot into old kernel, remove the file and create dir with
the same key. */
reiserfs_warning("green-2101: impossible truncate on a directory %k. Please report\n", INODE_PKEY (inode));
remove_save_link_only (s, &save_link_key, 0);
truncate = 0;
iput (inode);
continue;
}
if (truncate) {
inode -> u.reiserfs_i.i_flags |= i_link_saved_truncate_mask;
/* not completed truncate found. New size was committed together
with "save" link */
reiserfs_warning ("Truncating %k to %Ld ..",
INODE_PKEY (inode), inode->i_size);
reiserfs_truncate_file (inode, 0/*don't update modification time*/);
remove_save_link (inode, truncate);
} else {
inode -> u.reiserfs_i.i_flags |= i_link_saved_unlink_mask;
/* not completed unlink (rmdir) found */
reiserfs_warning ("Removing %k..", INODE_PKEY (inode));
/* removal gets completed in iput */
}
iput (inode);
printk ("done\n");
done ++;
}
s -> u.reiserfs_sb.s_is_unlinked_ok = 0;
pathrelse (&path);
if (done)
reiserfs_warning ("There were %d uncompleted unlinks/truncates. "
"Completed\n", done);
}