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-rw-r--r--fs/ext4/inode.c149
1 files changed, 76 insertions, 73 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 05c4145..7dd9b50 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -429,16 +429,13 @@ static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind)
* ext4_find_goal - find a prefered place for allocation.
* @inode: owner
* @block: block we want
- * @chain: chain of indirect blocks
* @partial: pointer to the last triple within a chain
- * @goal: place to store the result.
*
* Normally this function find the prefered place for block allocation,
- * stores it in *@goal and returns zero.
+ * returns it.
*/
-
static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block,
- Indirect chain[4], Indirect *partial)
+ Indirect *partial)
{
struct ext4_block_alloc_info *block_i;
@@ -839,7 +836,7 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
ext4_init_block_alloc_info(inode);
- goal = ext4_find_goal(inode, iblock, chain, partial);
+ goal = ext4_find_goal(inode, iblock, partial);
/* the number of blocks need to allocate for [d,t]indirect blocks */
indirect_blks = (chain + depth) - partial - 1;
@@ -895,7 +892,16 @@ out:
return err;
}
-#define DIO_CREDITS (EXT4_RESERVE_TRANS_BLOCKS + 32)
+/* Maximum number of blocks we map for direct IO at once. */
+#define DIO_MAX_BLOCKS 4096
+/*
+ * Number of credits we need for writing DIO_MAX_BLOCKS:
+ * We need sb + group descriptor + bitmap + inode -> 4
+ * For B blocks with A block pointers per block we need:
+ * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
+ * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
+ */
+#define DIO_CREDITS 25
int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
unsigned long max_blocks, struct buffer_head *bh,
@@ -942,49 +948,31 @@ static int ext4_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
{
handle_t *handle = ext4_journal_current_handle();
- int ret = 0;
+ int ret = 0, started = 0;
unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
- if (!create)
- goto get_block; /* A read */
-
- if (max_blocks == 1)
- goto get_block; /* A single block get */
-
- if (handle->h_transaction->t_state == T_LOCKED) {
- /*
- * Huge direct-io writes can hold off commits for long
- * periods of time. Let this commit run.
- */
- ext4_journal_stop(handle);
- handle = ext4_journal_start(inode, DIO_CREDITS);
- if (IS_ERR(handle))
+ if (create && !handle) {
+ /* Direct IO write... */
+ if (max_blocks > DIO_MAX_BLOCKS)
+ max_blocks = DIO_MAX_BLOCKS;
+ handle = ext4_journal_start(inode, DIO_CREDITS +
+ 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
- goto get_block;
- }
-
- if (handle->h_buffer_credits <= EXT4_RESERVE_TRANS_BLOCKS) {
- /*
- * Getting low on buffer credits...
- */
- ret = ext4_journal_extend(handle, DIO_CREDITS);
- if (ret > 0) {
- /*
- * Couldn't extend the transaction. Start a new one.
- */
- ret = ext4_journal_restart(handle, DIO_CREDITS);
+ goto out;
}
+ started = 1;
}
-get_block:
- if (ret == 0) {
- ret = ext4_get_blocks_wrap(handle, inode, iblock,
+ ret = ext4_get_blocks_wrap(handle, inode, iblock,
max_blocks, bh_result, create, 0);
- if (ret > 0) {
- bh_result->b_size = (ret << inode->i_blkbits);
- ret = 0;
- }
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
}
+ if (started)
+ ext4_journal_stop(handle);
+out:
return ret;
}
@@ -1674,7 +1662,8 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
* if the machine crashes during the write.
*
* If the O_DIRECT write is intantiating holes inside i_size and the machine
- * crashes then stale disk data _may_ be exposed inside the file.
+ * crashes then stale disk data _may_ be exposed inside the file. But current
+ * VFS code falls back into buffered path in that case so we are safe.
*/
static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
const struct iovec *iov, loff_t offset,
@@ -1683,7 +1672,7 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
struct ext4_inode_info *ei = EXT4_I(inode);
- handle_t *handle = NULL;
+ handle_t *handle;
ssize_t ret;
int orphan = 0;
size_t count = iov_length(iov, nr_segs);
@@ -1691,17 +1680,21 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
if (rw == WRITE) {
loff_t final_size = offset + count;
- handle = ext4_journal_start(inode, DIO_CREDITS);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out;
- }
if (final_size > inode->i_size) {
+ /* Credits for sb + inode write */
+ handle = ext4_journal_start(inode, 2);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
ret = ext4_orphan_add(handle, inode);
- if (ret)
- goto out_stop;
+ if (ret) {
+ ext4_journal_stop(handle);
+ goto out;
+ }
orphan = 1;
ei->i_disksize = inode->i_size;
+ ext4_journal_stop(handle);
}
}
@@ -1709,18 +1702,21 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
offset, nr_segs,
ext4_get_block, NULL);
- /*
- * Reacquire the handle: ext4_get_block() can restart the transaction
- */
- handle = ext4_journal_current_handle();
-
-out_stop:
- if (handle) {
+ if (orphan) {
int err;
- if (orphan && inode->i_nlink)
+ /* Credits for sb + inode write */
+ handle = ext4_journal_start(inode, 2);
+ if (IS_ERR(handle)) {
+ /* This is really bad luck. We've written the data
+ * but cannot extend i_size. Bail out and pretend
+ * the write failed... */
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+ if (inode->i_nlink)
ext4_orphan_del(handle, inode);
- if (orphan && ret > 0) {
+ if (ret > 0) {
loff_t end = offset + ret;
if (end > inode->i_size) {
ei->i_disksize = end;
@@ -2683,21 +2679,31 @@ static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
}
}
-void ext4_read_inode(struct inode * inode)
+struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
{
struct ext4_iloc iloc;
struct ext4_inode *raw_inode;
- struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_inode_info *ei;
struct buffer_head *bh;
+ struct inode *inode;
+ long ret;
int block;
+ inode = iget_locked(sb, ino);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ ei = EXT4_I(inode);
#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
ei->i_acl = EXT4_ACL_NOT_CACHED;
ei->i_default_acl = EXT4_ACL_NOT_CACHED;
#endif
ei->i_block_alloc_info = NULL;
- if (__ext4_get_inode_loc(inode, &iloc, 0))
+ ret = __ext4_get_inode_loc(inode, &iloc, 0);
+ if (ret < 0)
goto bad_inode;
bh = iloc.bh;
raw_inode = ext4_raw_inode(&iloc);
@@ -2723,6 +2729,7 @@ void ext4_read_inode(struct inode * inode)
!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
/* this inode is deleted */
brelse (bh);
+ ret = -ESTALE;
goto bad_inode;
}
/* The only unlinked inodes we let through here have
@@ -2750,17 +2757,12 @@ void ext4_read_inode(struct inode * inode)
ei->i_data[block] = raw_inode->i_block[block];
INIT_LIST_HEAD(&ei->i_orphan);
- if (inode->i_ino >= EXT4_FIRST_INO(inode->i_sb) + 1 &&
- EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
- /*
- * When mke2fs creates big inodes it does not zero out
- * the unused bytes above EXT4_GOOD_OLD_INODE_SIZE,
- * so ignore those first few inodes.
- */
+ if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
EXT4_INODE_SIZE(inode->i_sb)) {
brelse (bh);
+ ret = -EIO;
goto bad_inode;
}
if (ei->i_extra_isize == 0) {
@@ -2814,11 +2816,12 @@ void ext4_read_inode(struct inode * inode)
}
brelse (iloc.bh);
ext4_set_inode_flags(inode);
- return;
+ unlock_new_inode(inode);
+ return inode;
bad_inode:
- make_bad_inode(inode);
- return;
+ iget_failed(inode);
+ return ERR_PTR(ret);
}
static int ext4_inode_blocks_set(handle_t *handle,
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