#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
+#include "ext4_extents.h"
static inline int ext4_begin_ordered_truncate(struct inode *inode,
loff_t new_size)
*/
int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
unsigned long max_blocks, struct buffer_head *bh,
- int create, int extend_disksize)
+ int create, int extend_disksize, int flag)
{
int retval;
* with create == 1 flag.
*/
down_write((&EXT4_I(inode)->i_data_sem));
+
+ /*
+ * if the caller is from delayed allocation writeout path
+ * we have already reserved fs blocks for allocation
+ * let the underlying get_block() function know to
+ * avoid double accounting
+ */
+ if (flag)
+ EXT4_I(inode)->i_delalloc_reserved_flag = 1;
/*
* We need to check for EXT4 here because migrate
* could have changed the inode type in between
~EXT4_EXT_MIGRATE;
}
}
+
+ if (flag) {
+ EXT4_I(inode)->i_delalloc_reserved_flag = 0;
+ /*
+ * Update reserved blocks/metadata blocks
+ * after successful block allocation
+ * which were deferred till now
+ */
+ if ((retval > 0) && buffer_delay(bh))
+ ext4_da_release_space(inode, retval, 0);
+ }
+
up_write((&EXT4_I(inode)->i_data_sem));
return retval;
}
}
ret = ext4_get_blocks_wrap(handle, inode, iblock,
- max_blocks, bh_result, create, 0);
+ max_blocks, bh_result, create, 0, 0);
if (ret > 0) {
bh_result->b_size = (ret << inode->i_blkbits);
ret = 0;
dummy.b_blocknr = -1000;
buffer_trace_init(&dummy.b_history);
err = ext4_get_blocks_wrap(handle, inode, block, 1,
- &dummy, create, 1);
+ &dummy, create, 1, 0);
/*
* ext4_get_blocks_handle() returns number of blocks
* mapped. 0 in case of a HOLE.
return ret ? ret : copied;
}
+/*
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate @blocks for non extent file based file
+ */
+static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks)
+{
+ int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ int ind_blks, dind_blks, tind_blks;
+
+ /* number of new indirect blocks needed */
+ ind_blks = (blocks + icap - 1) / icap;
+
+ dind_blks = (ind_blks + icap - 1) / icap;
+
+ tind_blks = 1;
+
+ return ind_blks + dind_blks + tind_blks;
+}
+
+/*
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate given number of blocks
+ */
+static int ext4_calc_metadata_amount(struct inode *inode, int blocks)
+{
+ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+ return ext4_ext_calc_metadata_amount(inode, blocks);
+
+ return ext4_indirect_calc_metadata_amount(inode, blocks);
+}
+
+static int ext4_da_reserve_space(struct inode *inode, int nrblocks)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ unsigned long md_needed, mdblocks, total = 0;
+
+ /*
+ * recalculate the amount of metadata blocks to reserve
+ * in order to allocate nrblocks
+ * worse case is one extent per block
+ */
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks;
+ mdblocks = ext4_calc_metadata_amount(inode, total);
+ BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks);
+
+ md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks;
+ total = md_needed + nrblocks;
+
+ if (ext4_has_free_blocks(sbi, total) < total) {
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ return -ENOSPC;
+ }
+
+ /* reduce fs free blocks counter */
+ percpu_counter_sub(&sbi->s_freeblocks_counter, total);
+
+ EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
+ EXT4_I(inode)->i_reserved_meta_blocks = mdblocks;
+
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ return 0; /* success */
+}
+
+void ext4_da_release_space(struct inode *inode, int used, int to_free)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int total, mdb, mdb_free, release;
+
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ /* recalculate the number of metablocks still need to be reserved */
+ total = EXT4_I(inode)->i_reserved_data_blocks - used - to_free;
+ mdb = ext4_calc_metadata_amount(inode, total);
+
+ /* figure out how many metablocks to release */
+ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+ mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb;
+
+ /* Account for allocated meta_blocks */
+ mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
+
+ release = to_free + mdb_free;
+
+ /* update fs free blocks counter for truncate case */
+ percpu_counter_add(&sbi->s_freeblocks_counter, release);
+
+ /* update per-inode reservations */
+ BUG_ON(used + to_free > EXT4_I(inode)->i_reserved_data_blocks);
+ EXT4_I(inode)->i_reserved_data_blocks -= (used + to_free);
+
+ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+ EXT4_I(inode)->i_reserved_meta_blocks = mdb;
+ EXT4_I(inode)->i_allocated_meta_blocks = 0;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+}
+
+static void ext4_da_page_release_reservation(struct page *page,
+ unsigned long offset)
+{
+ int to_release = 0;
+ struct buffer_head *head, *bh;
+ unsigned int curr_off = 0;
+
+ head = page_buffers(page);
+ bh = head;
+ do {
+ unsigned int next_off = curr_off + bh->b_size;
+
+ if ((offset <= curr_off) && (buffer_delay(bh))) {
+ to_release++;
+ clear_buffer_delay(bh);
+ }
+ curr_off = next_off;
+ } while ((bh = bh->b_this_page) != head);
+ ext4_da_release_space(page->mapping->host, 0, to_release);
+}
/*
* Delayed allocation stuff
* preallocated blocks are unmapped but should treated
* the same as allocated blocks.
*/
- ret = ext4_get_blocks_wrap(NULL, inode, iblock, 1, bh_result, 0, 0);
- if (ret == 0) {
- /* the block isn't allocated yet, let's reserve space */
- /* XXX: call reservation here */
+ ret = ext4_get_blocks_wrap(NULL, inode, iblock, 1, bh_result, 0, 0, 0);
+ if ((ret == 0) && !buffer_delay(bh_result)) {
+ /* the block isn't (pre)allocated yet, let's reserve space */
/*
* XXX: __block_prepare_write() unmaps passed block,
* is it OK?
*/
+ ret = ext4_da_reserve_space(inode, 1);
+ if (ret)
+ /* not enough space to reserve */
+ return ret;
+
map_bh(bh_result, inode->i_sb, 0);
set_buffer_new(bh_result);
set_buffer_delay(bh_result);
return ret;
}
-
+#define EXT4_DELALLOC_RSVED 1
static int ext4_da_get_block_write(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
{
}
ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
- bh_result, create, 0);
+ bh_result, create, 0, EXT4_DELALLOC_RSVED);
if (ret > 0) {
bh_result->b_size = (ret << inode->i_blkbits);
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- int ret;
+ int ret, retries = 0;
struct page *page;
pgoff_t index;
unsigned from, to;
from = pos & (PAGE_CACHE_SIZE - 1);
to = from + len;
+retry:
/*
* With delayed allocation, we don't log the i_disksize update
* if there is delayed block allocation. But we still need
page_cache_release(page);
}
+ if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
out:
return ret;
}
static void ext4_da_invalidatepage(struct page *page, unsigned long offset)
{
- struct buffer_head *head, *bh;
- unsigned int curr_off = 0;
-
/*
* Drop reserved blocks
*/
if (!page_has_buffers(page))
goto out;
- head = page_buffers(page);
- bh = head;
- do {
- unsigned int next_off = curr_off + bh->b_size;
-
- /*
- * is this block fully invalidated?
- */
- if (offset <= curr_off && buffer_delay(bh)) {
- clear_buffer_delay(bh);
- /* XXX: add real stuff here */
- }
- curr_off = next_off;
- bh = bh->b_this_page;
- } while (bh != head);
+ ext4_da_page_release_reservation(page, offset);
out:
ext4_invalidatepage(page, offset);
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blobdiff