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reiserfs: don't wank with EFBIG before calling do_sync_write()

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look for file_capable() in there...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2013-03-19 19:46:45 -04:00
parent 97216be09e
commit d5daaaff24
1 changed files with 1 additions and 60 deletions
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61
fs/reiserfs/file.c
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@ -234,68 +234,9 @@ int reiserfs_commit_page(struct inode *inode, struct page *page,
return ret;
}
/* Write @count bytes at position @ppos in a file indicated by @file
from the buffer @buf.
generic_file_write() is only appropriate for filesystems that are not seeking to optimize performance and want
something simple that works. It is not for serious use by general purpose filesystems, excepting the one that it was
written for (ext2/3). This is for several reasons:
* It has no understanding of any filesystem specific optimizations.
* It enters the filesystem repeatedly for each page that is written.
* It depends on reiserfs_get_block() function which if implemented by reiserfs performs costly search_by_key
* operation for each page it is supplied with. By contrast reiserfs_file_write() feeds as much as possible at a time
* to reiserfs which allows for fewer tree traversals.
* Each indirect pointer insertion takes a lot of cpu, because it involves memory moves inside of blocks.
* Asking the block allocation code for blocks one at a time is slightly less efficient.
All of these reasons for not using only generic file write were understood back when reiserfs was first miscoded to
use it, but we were in a hurry to make code freeze, and so it couldn't be revised then. This new code should make
things right finally.
Future Features: providing search_by_key with hints.
*/
static ssize_t reiserfs_file_write(struct file *file, /* the file we are going to write into */
const char __user * buf, /* pointer to user supplied data
(in userspace) */
size_t count, /* amount of bytes to write */
loff_t * ppos /* pointer to position in file that we start writing at. Should be updated to
* new current position before returning. */
)
{
struct inode *inode = file_inode(file); // Inode of the file that we are writing to.
/* To simplify coding at this time, we store
locked pages in array for now */
struct reiserfs_transaction_handle th;
th.t_trans_id = 0;
/* If a filesystem is converted from 3.5 to 3.6, we'll have v3.5 items
* lying around (most of the disk, in fact). Despite the filesystem
* now being a v3.6 format, the old items still can't support large
* file sizes. Catch this case here, as the rest of the VFS layer is
* oblivious to the different limitations between old and new items.
* reiserfs_setattr catches this for truncates. This chunk is lifted
* from generic_write_checks. */
if (get_inode_item_key_version (inode) == KEY_FORMAT_3_5 &&
*ppos + count > MAX_NON_LFS) {
if (*ppos >= MAX_NON_LFS) {
return -EFBIG;
}
if (count > MAX_NON_LFS - (unsigned long)*ppos)
count = MAX_NON_LFS - (unsigned long)*ppos;
}
return do_sync_write(file, buf, count, ppos);
}
const struct file_operations reiserfs_file_operations = {
.read = do_sync_read,
.write = reiserfs_file_write,
.write = do_sync_write,
.unlocked_ioctl = reiserfs_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = reiserfs_compat_ioctl,