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kill generic_file_direct_IO()

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generic_file_direct_IO is a common helper around the invocation of
->direct_IO.  But there's almost nothing shared between the read and write
side, so we're better off without this helper.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2008-07-23 21:27:04 -07:00 committed by Linus Torvalds
parent 75353bed36
commit a969e903a9
1 changed files with 51 additions and 66 deletions
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117
mm/filemap.c
View file

@ -42,9 +42,6 @@
#include <asm/mman.h>
static ssize_t
generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
loff_t offset, unsigned long nr_segs);
/*
* Shared mappings implemented 30.11.1994. It's not fully working yet,
@ -1205,8 +1202,11 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
goto out; /* skip atime */
size = i_size_read(inode);
if (pos < size) {
retval = generic_file_direct_IO(READ, iocb,
iov, pos, nr_segs);
retval = filemap_write_and_wait(mapping);
if (!retval) {
retval = mapping->a_ops->direct_IO(READ, iocb,
iov, pos, nr_segs);
}
if (retval > 0)
*ppos = pos + retval;
}
@ -2004,11 +2004,55 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
struct address_space *mapping = file->f_mapping;
struct inode *inode = mapping->host;
ssize_t written;
size_t write_len;
pgoff_t end;
if (count != ocount)
*nr_segs = iov_shorten((struct iovec *)iov, *nr_segs, count);
written = generic_file_direct_IO(WRITE, iocb, iov, pos, *nr_segs);
/*
* Unmap all mmappings of the file up-front.
*
* This will cause any pte dirty bits to be propagated into the
* pageframes for the subsequent filemap_write_and_wait().
*/
write_len = iov_length(iov, *nr_segs);
end = (pos + write_len - 1) >> PAGE_CACHE_SHIFT;
if (mapping_mapped(mapping))
unmap_mapping_range(mapping, pos, write_len, 0);
written = filemap_write_and_wait(mapping);
if (written)
goto out;
/*
* After a write we want buffered reads to be sure to go to disk to get
* the new data. We invalidate clean cached page from the region we're
* about to write. We do this *before* the write so that we can return
* -EIO without clobbering -EIOCBQUEUED from ->direct_IO().
*/
if (mapping->nrpages) {
written = invalidate_inode_pages2_range(mapping,
pos >> PAGE_CACHE_SHIFT, end);
if (written)
goto out;
}
written = mapping->a_ops->direct_IO(WRITE, iocb, iov, pos, *nr_segs);
/*
* Finally, try again to invalidate clean pages which might have been
* cached by non-direct readahead, or faulted in by get_user_pages()
* if the source of the write was an mmap'ed region of the file
* we're writing. Either one is a pretty crazy thing to do,
* so we don't support it 100%. If this invalidation
* fails, tough, the write still worked...
*/
if (mapping->nrpages) {
invalidate_inode_pages2_range(mapping,
pos >> PAGE_CACHE_SHIFT, end);
}
if (written > 0) {
loff_t end = pos + written;
if (end > i_size_read(inode) && !S_ISBLK(inode->i_mode)) {
@ -2024,6 +2068,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
* i_mutex is held, which protects generic_osync_inode() from
* livelocking. AIO O_DIRECT ops attempt to sync metadata here.
*/
out:
if ((written >= 0 || written == -EIOCBQUEUED) &&
((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);
@ -2511,66 +2556,6 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
}
EXPORT_SYMBOL(generic_file_aio_write);
/*
* Called under i_mutex for writes to S_ISREG files. Returns -EIO if something
* went wrong during pagecache shootdown.
*/
static ssize_t
generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
loff_t offset, unsigned long nr_segs)
{
struct file *file = iocb->ki_filp;
struct address_space *mapping = file->f_mapping;
ssize_t retval;
size_t write_len;
pgoff_t end = 0; /* silence gcc */
/*
* If it's a write, unmap all mmappings of the file up-front. This
* will cause any pte dirty bits to be propagated into the pageframes
* for the subsequent filemap_write_and_wait().
*/
if (rw == WRITE) {
write_len = iov_length(iov, nr_segs);
end = (offset + write_len - 1) >> PAGE_CACHE_SHIFT;
if (mapping_mapped(mapping))
unmap_mapping_range(mapping, offset, write_len, 0);
}
retval = filemap_write_and_wait(mapping);
if (retval)
goto out;
/*
* After a write we want buffered reads to be sure to go to disk to get
* the new data. We invalidate clean cached page from the region we're
* about to write. We do this *before* the write so that we can return
* -EIO without clobbering -EIOCBQUEUED from ->direct_IO().
*/
if (rw == WRITE && mapping->nrpages) {
retval = invalidate_inode_pages2_range(mapping,
offset >> PAGE_CACHE_SHIFT, end);
if (retval)
goto out;
}
retval = mapping->a_ops->direct_IO(rw, iocb, iov, offset, nr_segs);
/*
* Finally, try again to invalidate clean pages which might have been
* cached by non-direct readahead, or faulted in by get_user_pages()
* if the source of the write was an mmap'ed region of the file
* we're writing. Either one is a pretty crazy thing to do,
* so we don't support it 100%. If this invalidation
* fails, tough, the write still worked...
*/
if (rw == WRITE && mapping->nrpages) {
invalidate_inode_pages2_range(mapping, offset >> PAGE_CACHE_SHIFT, end);
}
out:
return retval;
}
/**
* try_to_release_page() - release old fs-specific metadata on a page
*