int __generic_block_fiemap(struct inode *inode,
struct fiemap_extent_info *fieinfo, loff_t start,
loff_t len, get_block_t *get_block)
{
struct buffer_head map_bh;
sector_t start_blk, last_blk;
loff_t isize = i_size_read(inode);
u64 logical = 0, phys = 0, size = 0;
u32 flags = FIEMAP_EXTENT_MERGED;
bool past_eof = false, whole_file = false;
int ret = 0;
ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
if (ret)
return ret;
/*
* Either the i_mutex or other appropriate locking needs to be held
* since we expect isize to not change at all through the duration of
* this call.
*/
if (len >= isize) {
whole_file = true;
len = isize;
}
/*
* Some filesystems can't deal with being asked to map less than
* blocksize, so make sure our len is at least block length.
*/
if (logical_to_blk(inode, len) == 0)
len = blk_to_logical(inode, 1);
start_blk = logical_to_blk(inode, start);
last_blk = logical_to_blk(inode, start + len - 1);
do {
/*
* we set b_size to the total size we want so it will map as
* many contiguous blocks as possible at once
*/
memset(&map_bh, 0, sizeof(struct buffer_head));
map_bh.b_size = len;
ret = get_block(inode, start_blk, &map_bh, 0);
if (ret)
break;
/* HOLE */
if (!buffer_mapped(&map_bh)) {
start_blk++;
/*
* We want to handle the case where there is an
* allocated block at the front of the file, and then
* nothing but holes up to the end of the file properly,
* to make sure that extent at the front gets properly
* marked with FIEMAP_EXTENT_LAST
*/
if (!past_eof &&
blk_to_logical(inode, start_blk) >= isize)
past_eof = 1;
/*
* First hole after going past the EOF, this is our
* last extent
*/
if (past_eof && size) {
flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
} else if (size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size, flags);
size = 0;
}
/* if we have holes up to/past EOF then we're done */
if (start_blk > last_blk || past_eof || ret)
break;
} else {
/*
* We have gone over the length of what we wanted to
* map, and it wasn't the entire file, so add the extent
* we got last time and exit.
*
* This is for the case where say we want to map all the
* way up to the second to the last block in a file, but
* the last block is a hole, making the second to last
* block FIEMAP_EXTENT_LAST. In this case we want to
* see if there is a hole after the second to last block
* so we can mark it properly. If we found data after
* we exceeded the length we were requesting, then we
* are good to go, just add the extent to the fieinfo
* and break
*/
if (start_blk > last_blk && !whole_file) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
break;
}
/*
* if size != 0 then we know we already have an extent
* to add, so add it.
*/
if (size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
if (ret)
break;
}
logical = blk_to_logical(inode, start_blk);
phys = blk_to_logical(inode, map_bh.b_blocknr);
size = map_bh.b_size;
flags = FIEMAP_EXTENT_MERGED;
start_blk += logical_to_blk(inode, size);
/*
* If we are past the EOF, then we need to make sure as
* soon as we find a hole that the last extent we found
* is marked with FIEMAP_EXTENT_LAST
*/
if (!past_eof && logical + size >= isize)
past_eof = true;
}
cond_resched();
} while (1);
/* If ret is 1 then we just hit the end of the extent array */
if (ret == 1)
ret = 0;
return ret;
}
/*
* @inode - the inode to map
* @arg - the pointer to userspace where we copy everything to
* @get_block - the fs's get_block function
*
* This does FIEMAP for block based inodes. Basically it will just loop
* through get_block until we hit the number of extents we want to map, or we
* go past the end of the file and hit a hole.
*
* If it is possible to have data blocks beyond a hole past @inode->i_size, then
* please do not use this function, it will stop at the first unmapped block
* beyond i_size
*/
int generic_block_fiemap(struct inode *inode,
struct fiemap_extent_info *fieinfo, u64 start,
u64 len, get_block_t *get_block)
{
struct buffer_head tmp;
unsigned int start_blk;
long long length = 0, map_len = 0;
u64 logical = 0, phys = 0, size = 0;
u32 flags = FIEMAP_EXTENT_MERGED;
int ret = 0;
if ((ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC)))
return ret;
start_blk = logical_to_blk(inode, start);
/* guard against change */
mutex_lock(&inode->i_mutex);
length = (long long)min_t(u64, len, i_size_read(inode));
map_len = length;
do {
/*
* we set b_size to the total size we want so it will map as
* many contiguous blocks as possible at once
*/
memset(&tmp, 0, sizeof(struct buffer_head));
tmp.b_size = map_len;
ret = get_block(inode, start_blk, &tmp, 0);
if (ret)
break;
/* HOLE */
if (!buffer_mapped(&tmp)) {
/*
* first hole after going past the EOF, this is our
* last extent
*/
if (length <= 0) {
flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
break;
}
length -= blk_to_logical(inode, 1);
/* if we have holes up to/past EOF then we're done */
if (length <= 0)
break;
start_blk++;
} else {
if (length <= 0 && size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
if (ret)
break;
}
logical = blk_to_logical(inode, start_blk);
phys = blk_to_logical(inode, tmp.b_blocknr);
size = tmp.b_size;
flags = FIEMAP_EXTENT_MERGED;
length -= tmp.b_size;
start_blk += logical_to_blk(inode, size);
/*
* if we are past the EOF we need to loop again to see
* if there is a hole so we can mark this extent as the
* last one, and if not keep mapping things until we
* find a hole, or we run out of slots in the extent
* array
*/
if (length <= 0)
continue;
ret = fiemap_fill_next_extent(fieinfo, logical, phys,
size, flags);
if (ret)
break;
}
cond_resched();
} while (1);
mutex_unlock(&inode->i_mutex);
/* if ret is 1 then we just hit the end of the extent array */
if (ret == 1)
ret = 0;
return ret;
}
int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
struct buffer_head map_bh;
sector_t start_blk, last_blk;
loff_t isize = i_size_read(inode);
u64 logical = 0, phys = 0, size = 0;
u32 flags = 0;
bool past_eof = false, whole_file = false;
int ret = 0;
ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
if (ret)
return ret;
mutex_lock(&inode->i_mutex);
if (len >= isize) {
whole_file = true;
len = isize;
}
if (logical_to_blk(inode, len) == 0)
len = blk_to_logical(inode, 1);
start_blk = logical_to_blk(inode, start);
last_blk = logical_to_blk(inode, start + len - 1);
next:
memset(&map_bh, 0, sizeof(struct buffer_head));
map_bh.b_size = len;
ret = get_data_block(inode, start_blk, &map_bh, 0,
F2FS_GET_BLOCK_FIEMAP);
if (ret)
goto out;
/* HOLE */
if (!buffer_mapped(&map_bh)) {
start_blk++;
if (!past_eof && blk_to_logical(inode, start_blk) >= isize)
past_eof = 1;
if (past_eof && size) {
flags |= FIEMAP_EXTENT_LAST;
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size, flags);
} else if (size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size, flags);
size = 0;
}
/* if we have holes up to/past EOF then we're done */
if (start_blk > last_blk || past_eof || ret)
goto out;
} else {
if (start_blk > last_blk && !whole_file) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size, flags);
goto out;
}
/*
* if size != 0 then we know we already have an extent
* to add, so add it.
*/
if (size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size, flags);
if (ret)
goto out;
}
logical = blk_to_logical(inode, start_blk);
phys = blk_to_logical(inode, map_bh.b_blocknr);
size = map_bh.b_size;
flags = 0;
if (buffer_unwritten(&map_bh))
flags = FIEMAP_EXTENT_UNWRITTEN;
start_blk += logical_to_blk(inode, size);
/*
* If we are past the EOF, then we need to make sure as
* soon as we find a hole that the last extent we found
* is marked with FIEMAP_EXTENT_LAST
*/
if (!past_eof && logical + size >= isize)
past_eof = true;
}
cond_resched();
if (fatal_signal_pending(current))
ret = -EINTR;
else
goto next;
out:
if (ret == 1)
ret = 0;
mutex_unlock(&inode->i_mutex);
return ret;
}
int __generic_block_fiemap(struct inode *inode,
struct fiemap_extent_info *fieinfo, u64 start,
u64 len, get_block_t *get_block)
{
struct buffer_head tmp;
unsigned long long start_blk;
long long length = 0, map_len = 0;
u64 logical = 0, phys = 0, size = 0;
u32 flags = FIEMAP_EXTENT_MERGED;
int ret = 0, past_eof = 0, whole_file = 0;
if ((ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC)))
return ret;
start_blk = logical_to_blk(inode, start);
length = (long long)min_t(u64, len, i_size_read(inode));
if (length < len)
whole_file = 1;
map_len = length;
do {
/*
* we set b_size to the total size we want so it will map as
* many contiguous blocks as possible at once
*/
memset(&tmp, 0, sizeof(struct buffer_head));
tmp.b_size = map_len;
ret = get_block(inode, start_blk, &tmp, 0);
if (ret)
break;
/* HOLE */
if (!buffer_mapped(&tmp)) {
length -= blk_to_logical(inode, 1);
start_blk++;
/*
* we want to handle the case where there is an
* allocated block at the front of the file, and then
* nothing but holes up to the end of the file properly,
* to make sure that extent at the front gets properly
* marked with FIEMAP_EXTENT_LAST
*/
if (!past_eof &&
blk_to_logical(inode, start_blk) >=
blk_to_logical(inode, 0)+i_size_read(inode))
past_eof = 1;
/*
* first hole after going past the EOF, this is our
* last extent
*/
if (past_eof && size) {
flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
break;
}
/* if we have holes up to/past EOF then we're done */
if (length <= 0 || past_eof)
break;
} else {
/*
* we have gone over the length of what we wanted to
* map, and it wasn't the entire file, so add the extent
* we got last time and exit.
*
* This is for the case where say we want to map all the
* way up to the second to the last block in a file, but
* the last block is a hole, making the second to last
* block FIEMAP_EXTENT_LAST. In this case we want to
* see if there is a hole after the second to last block
* so we can mark it properly. If we found data after
* we exceeded the length we were requesting, then we
* are good to go, just add the extent to the fieinfo
* and break
*/
if (length <= 0 && !whole_file) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
break;
}
/*
* if size != 0 then we know we already have an extent
* to add, so add it.
*/
if (size) {
ret = fiemap_fill_next_extent(fieinfo, logical,
phys, size,
flags);
if (ret)
break;
}
logical = blk_to_logical(inode, start_blk);
phys = blk_to_logical(inode, tmp.b_blocknr);
size = tmp.b_size;
flags = FIEMAP_EXTENT_MERGED;
length -= tmp.b_size;
start_blk += logical_to_blk(inode, size);
/*
* If we are past the EOF, then we need to make sure as
* soon as we find a hole that the last extent we found
* is marked with FIEMAP_EXTENT_LAST
*/
if (!past_eof &&
logical+size >=
blk_to_logical(inode, 0)+i_size_read(inode))
past_eof = 1;
}
cond_resched();
} while (1);
/* if ret is 1 then we just hit the end of the extent array */
if (ret == 1)
ret = 0;
return ret;
}
