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Diffstat (limited to 'fs/ext4/inode.c')
-rw-r--r--fs/ext4/inode.c512
1 files changed, 443 insertions, 69 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 0defe0bfe019..f2419a15b81a 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -42,7 +42,6 @@
#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
-#include "ext4_extents.h"
#include "truncate.h"
#include <trace/events/ext4.h>
@@ -268,7 +267,7 @@ void ext4_da_update_reserve_space(struct inode *inode,
struct ext4_inode_info *ei = EXT4_I(inode);
spin_lock(&ei->i_block_reservation_lock);
- trace_ext4_da_update_reserve_space(inode, used);
+ trace_ext4_da_update_reserve_space(inode, used, quota_claim);
if (unlikely(used > ei->i_reserved_data_blocks)) {
ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, used %d "
"with only %d reserved data blocks\n",
@@ -281,7 +280,7 @@ void ext4_da_update_reserve_space(struct inode *inode,
/* Update per-inode reservations */
ei->i_reserved_data_blocks -= used;
ei->i_reserved_meta_blocks -= ei->i_allocated_meta_blocks;
- percpu_counter_sub(&sbi->s_dirtyblocks_counter,
+ percpu_counter_sub(&sbi->s_dirtyclusters_counter,
used + ei->i_allocated_meta_blocks);
ei->i_allocated_meta_blocks = 0;
@@ -291,7 +290,7 @@ void ext4_da_update_reserve_space(struct inode *inode,
* only when we have written all of the delayed
* allocation blocks.
*/
- percpu_counter_sub(&sbi->s_dirtyblocks_counter,
+ percpu_counter_sub(&sbi->s_dirtyclusters_counter,
ei->i_reserved_meta_blocks);
ei->i_reserved_meta_blocks = 0;
ei->i_da_metadata_calc_len = 0;
@@ -300,14 +299,14 @@ void ext4_da_update_reserve_space(struct inode *inode,
/* Update quota subsystem for data blocks */
if (quota_claim)
- dquot_claim_block(inode, used);
+ dquot_claim_block(inode, EXT4_C2B(sbi, used));
else {
/*
* We did fallocate with an offset that is already delayed
* allocated. So on delayed allocated writeback we should
* not re-claim the quota for fallocated blocks.
*/
- dquot_release_reservation_block(inode, used);
+ dquot_release_reservation_block(inode, EXT4_C2B(sbi, used));
}
/*
@@ -399,6 +398,49 @@ static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
}
/*
+ * Sets the BH_Da_Mapped bit on the buffer heads corresponding to the given map.
+ */
+static void set_buffers_da_mapped(struct inode *inode,
+ struct ext4_map_blocks *map)
+{
+ struct address_space *mapping = inode->i_mapping;
+ struct pagevec pvec;
+ int i, nr_pages;
+ pgoff_t index, end;
+
+ index = map->m_lblk >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ end = (map->m_lblk + map->m_len - 1) >>
+ (PAGE_CACHE_SHIFT - inode->i_blkbits);
+
+ pagevec_init(&pvec, 0);
+ while (index <= end) {
+ nr_pages = pagevec_lookup(&pvec, mapping, index,
+ min(end - index + 1,
+ (pgoff_t)PAGEVEC_SIZE));
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+ struct buffer_head *bh, *head;
+
+ if (unlikely(page->mapping != mapping) ||
+ !PageDirty(page))
+ break;
+
+ if (page_has_buffers(page)) {
+ bh = head = page_buffers(page);
+ do {
+ set_buffer_da_mapped(bh);
+ bh = bh->b_this_page;
+ } while (bh != head);
+ }
+ index++;
+ }
+ pagevec_release(&pvec);
+ }
+}
+
+/*
* The ext4_map_blocks() function tries to look up the requested blocks,
* and returns if the blocks are already mapped.
*
@@ -416,7 +458,7 @@ static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
* the buffer head is mapped.
*
* It returns 0 if plain look up failed (blocks have not been allocated), in
- * that casem, buffer head is unmapped
+ * that case, buffer head is unmapped
*
* It returns the error in case of allocation failure.
*/
@@ -435,9 +477,11 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
*/
down_read((&EXT4_I(inode)->i_data_sem));
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
- retval = ext4_ext_map_blocks(handle, inode, map, 0);
+ retval = ext4_ext_map_blocks(handle, inode, map, flags &
+ EXT4_GET_BLOCKS_KEEP_SIZE);
} else {
- retval = ext4_ind_map_blocks(handle, inode, map, 0);
+ retval = ext4_ind_map_blocks(handle, inode, map, flags &
+ EXT4_GET_BLOCKS_KEEP_SIZE);
}
up_read((&EXT4_I(inode)->i_data_sem));
@@ -455,7 +499,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
* Returns if the blocks have already allocated
*
* Note that if blocks have been preallocated
- * ext4_ext_get_block() returns th create = 0
+ * ext4_ext_get_block() returns the create = 0
* with buffer head unmapped.
*/
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
@@ -517,9 +561,17 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE))
ext4_da_update_reserve_space(inode, retval, 1);
}
- if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
+ if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
ext4_clear_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
+ /* If we have successfully mapped the delayed allocated blocks,
+ * set the BH_Da_Mapped bit on them. Its important to do this
+ * under the protection of i_data_sem.
+ */
+ if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
+ set_buffers_da_mapped(inode, map);
+ }
+
up_write((&EXT4_I(inode)->i_data_sem));
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
int ret = check_block_validity(inode, map);
@@ -909,7 +961,11 @@ static int ext4_ordered_write_end(struct file *file,
ext4_orphan_add(handle, inode);
if (ret2 < 0)
ret = ret2;
+ } else {
+ unlock_page(page);
+ page_cache_release(page);
}
+
ret2 = ext4_journal_stop(handle);
if (!ret)
ret = ret2;
@@ -1037,14 +1093,14 @@ static int ext4_journalled_write_end(struct file *file,
}
/*
- * Reserve a single block located at lblock
+ * Reserve a single cluster located at lblock
*/
static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)
{
int retries = 0;
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
struct ext4_inode_info *ei = EXT4_I(inode);
- unsigned long md_needed;
+ unsigned int md_needed;
int ret;
/*
@@ -1054,7 +1110,8 @@ static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)
*/
repeat:
spin_lock(&ei->i_block_reservation_lock);
- md_needed = ext4_calc_metadata_amount(inode, lblock);
+ md_needed = EXT4_NUM_B2C(sbi,
+ ext4_calc_metadata_amount(inode, lblock));
trace_ext4_da_reserve_space(inode, md_needed);
spin_unlock(&ei->i_block_reservation_lock);
@@ -1063,15 +1120,15 @@ repeat:
* us from metadata over-estimation, though we may go over by
* a small amount in the end. Here we just reserve for data.
*/
- ret = dquot_reserve_block(inode, 1);
+ ret = dquot_reserve_block(inode, EXT4_C2B(sbi, 1));
if (ret)
return ret;
/*
* We do still charge estimated metadata to the sb though;
* we cannot afford to run out of free blocks.
*/
- if (ext4_claim_free_blocks(sbi, md_needed + 1, 0)) {
- dquot_release_reservation_block(inode, 1);
+ if (ext4_claim_free_clusters(sbi, md_needed + 1, 0)) {
+ dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));
if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
yield();
goto repeat;
@@ -1118,19 +1175,21 @@ static void ext4_da_release_space(struct inode *inode, int to_free)
* We can release all of the reserved metadata blocks
* only when we have written all of the delayed
* allocation blocks.
+ * Note that in case of bigalloc, i_reserved_meta_blocks,
+ * i_reserved_data_blocks, etc. refer to number of clusters.
*/
- percpu_counter_sub(&sbi->s_dirtyblocks_counter,
+ percpu_counter_sub(&sbi->s_dirtyclusters_counter,
ei->i_reserved_meta_blocks);
ei->i_reserved_meta_blocks = 0;
ei->i_da_metadata_calc_len = 0;
}
/* update fs dirty data blocks counter */
- percpu_counter_sub(&sbi->s_dirtyblocks_counter, to_free);
+ percpu_counter_sub(&sbi->s_dirtyclusters_counter, to_free);
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
- dquot_release_reservation_block(inode, to_free);
+ dquot_release_reservation_block(inode, EXT4_C2B(sbi, to_free));
}
static void ext4_da_page_release_reservation(struct page *page,
@@ -1139,6 +1198,9 @@ static void ext4_da_page_release_reservation(struct page *page,
int to_release = 0;
struct buffer_head *head, *bh;
unsigned int curr_off = 0;
+ struct inode *inode = page->mapping->host;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int num_clusters;
head = page_buffers(page);
bh = head;
@@ -1148,10 +1210,24 @@ static void ext4_da_page_release_reservation(struct page *page,
if ((offset <= curr_off) && (buffer_delay(bh))) {
to_release++;
clear_buffer_delay(bh);
+ clear_buffer_da_mapped(bh);
}
curr_off = next_off;
} while ((bh = bh->b_this_page) != head);
- ext4_da_release_space(page->mapping->host, to_release);
+
+ /* If we have released all the blocks belonging to a cluster, then we
+ * need to release the reserved space for that cluster. */
+ num_clusters = EXT4_NUM_B2C(sbi, to_release);
+ while (num_clusters > 0) {
+ ext4_fsblk_t lblk;
+ lblk = (page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits)) +
+ ((num_clusters - 1) << sbi->s_cluster_bits);
+ if (sbi->s_cluster_ratio == 1 ||
+ !ext4_find_delalloc_cluster(inode, lblk, 1))
+ ext4_da_release_space(inode, 1);
+
+ num_clusters--;
+ }
}
/*
@@ -1253,6 +1329,8 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd,
clear_buffer_delay(bh);
bh->b_blocknr = pblock;
}
+ if (buffer_da_mapped(bh))
+ clear_buffer_da_mapped(bh);
if (buffer_unwritten(bh) ||
buffer_mapped(bh))
BUG_ON(bh->b_blocknr != pblock);
@@ -1346,12 +1424,15 @@ static void ext4_print_free_blocks(struct inode *inode)
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
printk(KERN_CRIT "Total free blocks count %lld\n",
- ext4_count_free_blocks(inode->i_sb));
+ EXT4_C2B(EXT4_SB(inode->i_sb),
+ ext4_count_free_clusters(inode->i_sb)));
printk(KERN_CRIT "Free/Dirty block details\n");
printk(KERN_CRIT "free_blocks=%lld\n",
- (long long) percpu_counter_sum(&sbi->s_freeblocks_counter));
+ (long long) EXT4_C2B(EXT4_SB(inode->i_sb),
+ percpu_counter_sum(&sbi->s_freeclusters_counter)));
printk(KERN_CRIT "dirty_blocks=%lld\n",
- (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
+ (long long) EXT4_C2B(EXT4_SB(inode->i_sb),
+ percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
printk(KERN_CRIT "Block reservation details\n");
printk(KERN_CRIT "i_reserved_data_blocks=%u\n",
EXT4_I(inode)->i_reserved_data_blocks);
@@ -1430,8 +1511,7 @@ static void mpage_da_map_and_submit(struct mpage_da_data *mpd)
if (err == -EAGAIN)
goto submit_io;
- if (err == -ENOSPC &&
- ext4_count_free_blocks(sb)) {
+ if (err == -ENOSPC && ext4_count_free_clusters(sb)) {
mpd->retval = err;
goto submit_io;
}
@@ -1471,13 +1551,15 @@ static void mpage_da_map_and_submit(struct mpage_da_data *mpd)
for (i = 0; i < map.m_len; i++)
unmap_underlying_metadata(bdev, map.m_pblk + i);
- }
- if (ext4_should_order_data(mpd->inode)) {
- err = ext4_jbd2_file_inode(handle, mpd->inode);
- if (err)
- /* This only happens if the journal is aborted */
- return;
+ if (ext4_should_order_data(mpd->inode)) {
+ err = ext4_jbd2_file_inode(handle, mpd->inode);
+ if (err) {
+ /* Only if the journal is aborted */
+ mpd->retval = err;
+ goto submit_io;
+ }
+ }
}
/*
@@ -1584,6 +1666,66 @@ static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
}
/*
+ * This function is grabs code from the very beginning of
+ * ext4_map_blocks, but assumes that the caller is from delayed write
+ * time. This function looks up the requested blocks and sets the
+ * buffer delay bit under the protection of i_data_sem.
+ */
+static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
+ struct ext4_map_blocks *map,
+ struct buffer_head *bh)
+{
+ int retval;
+ sector_t invalid_block = ~((sector_t) 0xffff);
+
+ if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
+ invalid_block = ~0;
+
+ map->m_flags = 0;
+ ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
+ "logical block %lu\n", inode->i_ino, map->m_len,
+ (unsigned long) map->m_lblk);
+ /*
+ * Try to see if we can get the block without requesting a new
+ * file system block.
+ */
+ down_read((&EXT4_I(inode)->i_data_sem));
+ if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
+ retval = ext4_ext_map_blocks(NULL, inode, map, 0);
+ else
+ retval = ext4_ind_map_blocks(NULL, inode, map, 0);
+
+ if (retval == 0) {
+ /*
+ * XXX: __block_prepare_write() unmaps passed block,
+ * is it OK?
+ */
+ /* If the block was allocated from previously allocated cluster,
+ * then we dont need to reserve it again. */
+ if (!(map->m_flags & EXT4_MAP_FROM_CLUSTER)) {
+ retval = ext4_da_reserve_space(inode, iblock);
+ if (retval)
+ /* not enough space to reserve */
+ goto out_unlock;
+ }
+
+ /* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
+ * and it should not appear on the bh->b_state.
+ */
+ map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
+
+ map_bh(bh, inode->i_sb, invalid_block);
+ set_buffer_new(bh);
+ set_buffer_delay(bh);
+ }
+
+out_unlock:
+ up_read((&EXT4_I(inode)->i_data_sem));
+
+ return retval;
+}
+
+/*
* This is a special get_blocks_t callback which is used by
* ext4_da_write_begin(). It will either return mapped block or
* reserve space for a single block.
@@ -1600,10 +1742,6 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
{
struct ext4_map_blocks map;
int ret = 0;
- sector_t invalid_block = ~((sector_t) 0xffff);
-
- if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
- invalid_block = ~0;
BUG_ON(create == 0);
BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
@@ -1616,25 +1754,9 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
* preallocated blocks are unmapped but should treated
* the same as allocated blocks.
*/
- ret = ext4_map_blocks(NULL, inode, &map, 0);
- if (ret < 0)
+ ret = ext4_da_map_blocks(inode, iblock, &map, bh);
+ if (ret <= 0)
return ret;
- if (ret == 0) {
- if (buffer_delay(bh))
- return 0; /* Not sure this could or should happen */
- /*
- * XXX: __block_write_begin() unmaps passed block, is it OK?
- */
- ret = ext4_da_reserve_space(inode, iblock);
- if (ret)
- /* not enough space to reserve */
- return ret;
-
- map_bh(bh, inode->i_sb, invalid_block);
- set_buffer_new(bh);
- set_buffer_delay(bh);
- return 0;
- }
map_bh(bh, inode->i_sb, map.m_pblk);
bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
@@ -2050,6 +2172,7 @@ static int ext4_da_writepages(struct address_space *mapping,
struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
pgoff_t done_index = 0;
pgoff_t end;
+ struct blk_plug plug;
trace_ext4_da_writepages(inode, wbc);
@@ -2128,6 +2251,7 @@ retry:
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
tag_pages_for_writeback(mapping, index, end);
+ blk_start_plug(&plug);
while (!ret && wbc->nr_to_write > 0) {
/*
@@ -2178,11 +2302,12 @@ retry:
ret = 0;
} else if (ret == MPAGE_DA_EXTENT_TAIL) {
/*
- * got one extent now try with
- * rest of the pages
+ * Got one extent now try with rest of the pages.
+ * If mpd.retval is set -EIO, journal is aborted.
+ * So we don't need to write any more.
*/
pages_written += mpd.pages_written;
- ret = 0;
+ ret = mpd.retval;
io_done = 1;
} else if (wbc->nr_to_write)
/*
@@ -2192,6 +2317,7 @@ retry:
*/
break;
}
+ blk_finish_plug(&plug);
if (!io_done && !cycled) {
cycled = 1;
index = 0;
@@ -2230,10 +2356,11 @@ static int ext4_nonda_switch(struct super_block *sb)
* Delalloc need an accurate free block accounting. So switch
* to non delalloc when we are near to error range.
*/
- free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
- dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter);
+ free_blocks = EXT4_C2B(sbi,
+ percpu_counter_read_positive(&sbi->s_freeclusters_counter));
+ dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyclusters_counter);
if (2 * free_blocks < 3 * dirty_blocks ||
- free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) {
+ free_blocks < (dirty_blocks + EXT4_FREECLUSTERS_WATERMARK)) {
/*
* free block count is less than 150% of dirty blocks
* or free blocks is less than watermark
@@ -2259,6 +2386,7 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
pgoff_t index;
struct inode *inode = mapping->host;
handle_t *handle;
+ loff_t page_len;
index = pos >> PAGE_CACHE_SHIFT;
@@ -2305,6 +2433,13 @@ retry:
*/
if (pos + len > inode->i_size)
ext4_truncate_failed_write(inode);
+ } else {
+ page_len = pos & (PAGE_CACHE_SIZE - 1);
+ if (page_len > 0) {
+ ret = ext4_discard_partial_page_buffers_no_lock(handle,
+ inode, page, pos - page_len, page_len,
+ EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED);
+ }
}
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
@@ -2347,6 +2482,7 @@ static int ext4_da_write_end(struct file *file,
loff_t new_i_size;
unsigned long start, end;
int write_mode = (int)(unsigned long)fsdata;
+ loff_t page_len;
if (write_mode == FALL_BACK_TO_NONDELALLOC) {
if (ext4_should_order_data(inode)) {
@@ -2395,6 +2531,16 @@ static int ext4_da_write_end(struct file *file,
}
ret2 = generic_write_end(file, mapping, pos, len, copied,
page, fsdata);
+
+ page_len = PAGE_CACHE_SIZE -
+ ((pos + copied - 1) & (PAGE_CACHE_SIZE - 1));
+
+ if (page_len > 0) {
+ ret = ext4_discard_partial_page_buffers_no_lock(handle,
+ inode, page, pos + copied - 1, page_len,
+ EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED);
+ }
+
copied = ret2;
if (ret2 < 0)
ret = ret2;
@@ -2689,10 +2835,7 @@ static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)
* but being more careful is always safe for the future change.
*/
inode = io_end->inode;
- if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
- io_end->flag |= EXT4_IO_END_UNWRITTEN;
- atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
- }
+ ext4_set_io_unwritten_flag(inode, io_end);
/* Add the io_end to per-inode completed io list*/
spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
@@ -2858,6 +3001,12 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
struct inode *inode = file->f_mapping->host;
ssize_t ret;
+ /*
+ * If we are doing data journalling we don't support O_DIRECT
+ */
+ if (ext4_should_journal_data(inode))
+ return 0;
+
trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw);
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
@@ -2927,6 +3076,7 @@ static const struct address_space_operations ext4_journalled_aops = {
.bmap = ext4_bmap,
.invalidatepage = ext4_invalidatepage,
.releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
.is_partially_uptodate = block_is_partially_uptodate,
.error_remove_page = generic_error_remove_page,
};
@@ -2963,6 +3113,227 @@ void ext4_set_aops(struct inode *inode)
inode->i_mapping->a_ops = &ext4_journalled_aops;
}
+
+/*
+ * ext4_discard_partial_page_buffers()
+ * Wrapper function for ext4_discard_partial_page_buffers_no_lock.
+ * This function finds and locks the page containing the offset
+ * "from" and passes it to ext4_discard_partial_page_buffers_no_lock.
+ * Calling functions that already have the page locked should call
+ * ext4_discard_partial_page_buffers_no_lock directly.
+ */
+int ext4_discard_partial_page_buffers(handle_t *handle,
+ struct address_space *mapping, loff_t from,
+ loff_t length, int flags)
+{
+ struct inode *inode = mapping->host;
+ struct page *page;
+ int err = 0;
+
+ page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
+ mapping_gfp_mask(mapping) & ~__GFP_FS);
+ if (!page)
+ return -ENOMEM;
+
+ err = ext4_discard_partial_page_buffers_no_lock(handle, inode, page,
+ from, length, flags);
+
+ unlock_page(page);
+ page_cache_release(page);
+ return err;
+}
+
+/*
+ * ext4_discard_partial_page_buffers_no_lock()
+ * Zeros a page range of length 'length' starting from offset 'from'.
+ * Buffer heads that correspond to the block aligned regions of the
+ * zeroed range will be unmapped. Unblock aligned regions
+ * will have the corresponding buffer head mapped if needed so that
+ * that region of the page can be updated with the partial zero out.
+ *
+ * This function assumes that the page has already been locked. The
+ * The range to be discarded must be contained with in the given page.
+ * If the specified range exceeds the end of the page it will be shortened
+ * to the end of the page that corresponds to 'from'. This function is
+ * appropriate for updating a page and it buffer heads to be unmapped and
+ * zeroed for blocks that have been either released, or are going to be
+ * released.
+ *
+ * handle: The journal handle
+ * inode: The files inode
+ * page: A locked page that contains the offset "from"
+ * from: The starting byte offset (from the begining of the file)
+ * to begin discarding
+ * len: The length of bytes to discard
+ * flags: Optional flags that may be used:
+ *
+ * EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
+ * Only zero the regions of the page whose buffer heads
+ * have already been unmapped. This flag is appropriate
+ * for updateing the contents of a page whose blocks may
+ * have already been released, and we only want to zero
+ * out the regions that correspond to those released blocks.
+ *
+ * Returns zero on sucess or negative on failure.
+ */
+int ext4_discard_partial_page_buffers_no_lock(handle_t *handle,
+ struct inode *inode, struct page *page, loff_t from,
+ loff_t length, int flags)
+{
+ ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
+ unsigned int offset = from & (PAGE_CACHE_SIZE-1);
+ unsigned int blocksize, max, pos;
+ ext4_lblk_t iblock;
+ struct buffer_head *bh;
+ int err = 0;
+
+ blocksize = inode->i_sb->s_blocksize;
+ max = PAGE_CACHE_SIZE - offset;
+
+ if (index != page->index)
+ return -EINVAL;
+
+ /*
+ * correct length if it does not fall between
+ * 'from' and the end of the page
+ */
+ if (length > max || length < 0)
+ length = max;
+
+ iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
+
+ if (!page_has_buffers(page)) {
+ /*
+ * If the range to be discarded covers a partial block
+ * we need to get the page buffers. This is because
+ * partial blocks cannot be released and the page needs
+ * to be updated with the contents of the block before
+ * we write the zeros on top of it.
+ */
+ if ((from & (blocksize - 1)) ||
+ ((from + length) & (blocksize - 1))) {
+ create_empty_buffers(page, blocksize, 0);
+ } else {
+ /*
+ * If there are no partial blocks,
+ * there is nothing to update,
+ * so we can return now
+ */
+ return 0;
+ }
+ }
+
+ /* Find the buffer that contains "offset" */
+ bh = page_buffers(page);
+ pos = blocksize;
+ while (offset >= pos) {
+ bh = bh->b_this_page;
+ iblock++;
+ pos += blocksize;
+ }
+
+ pos = offset;
+ while (pos < offset + length) {
+ unsigned int end_of_block, range_to_discard;
+
+ err = 0;
+
+ /* The length of space left to zero and unmap */
+ range_to_discard = offset + length - pos;
+
+ /* The length of space until the end of the block */
+ end_of_block = blocksize - (pos & (blocksize-1));
+
+ /*
+ * Do not unmap or zero past end of block
+ * for this buffer head
+ */
+ if (range_to_discard > end_of_block)
+ range_to_discard = end_of_block;
+
+
+ /*
+ * Skip this buffer head if we are only zeroing unampped
+ * regions of the page
+ */
+ if (flags & EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED &&
+ buffer_mapped(bh))
+ goto next;
+
+ /* If the range is block aligned, unmap */
+ if (range_to_discard == blocksize) {
+ clear_buffer_dirty(bh);
+ bh->b_bdev = NULL;
+ clear_buffer_mapped(bh);
+ clear_buffer_req(bh);
+ clear_buffer_new(bh);
+ clear_buffer_delay(bh);
+ clear_buffer_unwritten(bh);
+ clear_buffer_uptodate(bh);
+ zero_user(page, pos, range_to_discard);
+ BUFFER_TRACE(bh, "Buffer discarded");
+ goto next;
+ }
+
+ /*
+ * If this block is not completely contained in the range
+ * to be discarded, then it is not going to be released. Because
+ * we need to keep this block, we need to make sure this part
+ * of the page is uptodate before we modify it by writeing
+ * partial zeros on it.
+ */
+ if (!buffer_mapped(bh)) {
+ /*
+ * Buffer head must be mapped before we can read
+ * from the block
+ */
+ BUFFER_TRACE(bh, "unmapped");
+ ext4_get_block(inode, iblock, bh, 0);
+ /* unmapped? It's a hole - nothing to do */
+ if (!buffer_mapped(bh)) {
+ BUFFER_TRACE(bh, "still unmapped");
+ goto next;
+ }
+ }
+
+ /* Ok, it's mapped. Make sure it's up-to-date */
+ if (PageUptodate(page))
+ set_buffer_uptodate(bh);
+
+ if (!buffer_uptodate(bh)) {
+ err = -EIO;
+ ll_rw_block(READ, 1, &bh);
+ wait_on_buffer(bh);
+ /* Uhhuh. Read error. Complain and punt.*/
+ if (!buffer_uptodate(bh))
+ goto next;
+ }
+
+ if (ext4_should_journal_data(inode)) {
+ BUFFER_TRACE(bh, "get write access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err)
+ goto next;
+ }
+
+ zero_user(page, pos, range_to_discard);
+
+ err = 0;
+ if (ext4_should_journal_data(inode)) {
+ err = ext4_handle_dirty_metadata(handle, inode, bh);
+ } else
+ mark_buffer_dirty(bh);
+
+ BUFFER_TRACE(bh, "Partial buffer zeroed");
+next:
+ bh = bh->b_this_page;
+ iblock++;
+ pos += range_to_discard;
+ }
+
+ return err;
+}
+
/*
* ext4_block_truncate_page() zeroes out a mapping from file offset `from'
* up to the end of the block which corresponds to `from'.
@@ -3005,7 +3376,7 @@ int ext4_block_zero_page_range(handle_t *handle,
page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
mapping_gfp_mask(mapping) & ~__GFP_FS);
if (!page)
- return -EINVAL;
+ return -ENOMEM;
blocksize = inode->i_sb->s_blocksize;
max = blocksize - (offset & (blocksize - 1));
@@ -3074,11 +3445,8 @@ int ext4_block_zero_page_range(handle_t *handle,
err = 0;
if (ext4_should_journal_data(inode)) {
err = ext4_handle_dirty_metadata(handle, inode, bh);
- } else {
- if (ext4_should_order_data(inode) && EXT4_I(inode)->jinode)
- err = ext4_jbd2_file_inode(handle, inode);
+ } else
mark_buffer_dirty(bh);
- }
unlock:
unlock_page(page);
@@ -3119,6 +3487,11 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
return -ENOTSUPP;
}
+ if (EXT4_SB(inode->i_sb)->s_cluster_ratio > 1) {
+ /* TODO: Add support for bigalloc file systems */
+ return -ENOTSUPP;
+ }
+
return ext4_ext_punch_hole(file, offset, length);
}
@@ -4420,6 +4793,7 @@ retry_alloc:
PAGE_CACHE_SIZE, NULL, do_journal_get_write_access)) {
unlock_page(page);
ret = VM_FAULT_SIGBUS;
+ ext4_journal_stop(handle);
goto out;
}
ext4_set_inode_state(inode, EXT4_STATE_JDATA);