NFS: clean up comments and tab damage in direct.c

 * 08 Jun 2003	Port to 2.5 APIs  --cel

 * 31 Mar 2004	Handle direct I/O without VFS support  --cel

 * 15 Sep 2004	Parallel async reads  --cel

 * 04 May 2005	support O_DIRECT with aio  --cel

 *

 */

 */

struct nfs_direct_req {

	struct kref		kref;		/* release manager */

	struct list_head	list;		/* nfs_read_data structs */

	struct list_head	list;		/* nfs_read/write_data structs */

	struct file *		filp;		/* file descriptor */

	struct kiocb *		iocb;		/* controlling i/o request */

	wait_queue_head_t	wait;		/* wait for i/o completion */

	struct inode *		inode;		/* target file of I/O */

	struct inode *		inode;		/* target file of i/o */

	struct page **		pages;		/* pages in our buffer */

	unsigned int		npages;		/* count of pages */

	atomic_t		complete,	/* i/os we're waiting for */

	size_t array_size;

	/* set an arbitrary limit to prevent type overflow */

	/* XXX: this can probably be as large as INT_MAX */

	if (size > MAX_DIRECTIO_SIZE) {

		*pages = NULL;

		return -EFBIG;

 * For each nfs_read_data struct that was allocated on the list, dispatch

 * an NFS READ operation

 */

static void nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t file_offset)

static void nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos)

{

	struct file *file = dreq->filp;

	struct inode *inode = file->f_mapping->host;

		data->cred = ctx->cred;

		data->args.fh = NFS_FH(inode);

		data->args.context = ctx;

		data->args.offset = file_offset;

		data->args.offset = pos;

		data->args.pgbase = pgbase;

		data->args.pages = &pages[curpage];

		data->args.count = bytes;

				bytes,

				(unsigned long long)data->args.offset);

		file_offset += bytes;

		pos += bytes;

		pgbase += bytes;

		curpage += pgbase >> PAGE_SHIFT;

		pgbase &= ~PAGE_MASK;

	} while (count != 0);

}

static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, unsigned int nr_pages)

static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos, struct page **pages, unsigned int nr_pages)

{

	ssize_t result;

	sigset_t oldset;

	nfs_add_stats(inode, NFSIOS_DIRECTREADBYTES, count);

	rpc_clnt_sigmask(clnt, &oldset);

	nfs_direct_read_schedule(dreq, user_addr, count, file_offset);

	nfs_direct_read_schedule(dreq, user_addr, count, pos);

	result = nfs_direct_wait(dreq);

	rpc_clnt_sigunmask(clnt, &oldset);

 * XXX: For now, support only FILE_SYNC writes.  Later we may add

 *      support for UNSTABLE + COMMIT.

 */

static void nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t file_offset)

static void nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos)

{

	struct file *file = dreq->filp;

	struct inode *inode = file->f_mapping->host;

		data->cred = ctx->cred;

		data->args.fh = NFS_FH(inode);

		data->args.context = ctx;

		data->args.offset = file_offset;

		data->args.offset = pos;

		data->args.pgbase = pgbase;

		data->args.pages = &pages[curpage];

		data->args.count = bytes;

				bytes,

				(unsigned long long)data->args.offset);

		file_offset += bytes;

		pos += bytes;

		pgbase += bytes;

		curpage += pgbase >> PAGE_SHIFT;

		pgbase &= ~PAGE_MASK;

	} while (count != 0);

}

static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, int nr_pages)

static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos, struct page **pages, int nr_pages)

{

	ssize_t result;

	sigset_t oldset;

	nfs_begin_data_update(inode);

	rpc_clnt_sigmask(clnt, &oldset);

	nfs_direct_write_schedule(dreq, user_addr, count, file_offset);

	nfs_direct_write_schedule(dreq, user_addr, count, pos);

	result = nfs_direct_wait(dreq);

	rpc_clnt_sigunmask(clnt, &oldset);

 * nfs_file_direct_read - file direct read operation for NFS files

 * @iocb: target I/O control block

 * @buf: user's buffer into which to read data

 * count: number of bytes to read

 * pos: byte offset in file where reading starts

 * @count: number of bytes to read

 * @pos: byte offset in file where reading starts

 *

 * We use this function for direct reads instead of calling

 * generic_file_aio_read() in order to avoid gfar's check to see if

 * the request starts before the end of the file.  For that check

 * to work, we must generate a GETATTR before each direct read, and

 * even then there is a window between the GETATTR and the subsequent

 * READ where the file size could change.  So our preference is simply

 * READ where the file size could change.  Our preference is simply

 * to do all reads the application wants, and the server will take

 * care of managing the end of file boundary.

 *

 * nfs_file_direct_write - file direct write operation for NFS files

 * @iocb: target I/O control block

 * @buf: user's buffer from which to write data

 * count: number of bytes to write

 * pos: byte offset in file where writing starts

 * @count: number of bytes to write

 * @pos: byte offset in file where writing starts

 *

 * We use this function for direct writes instead of calling

 * generic_file_aio_write() in order to avoid taking the inode

	return retval;

}

/**

 * nfs_init_directcache - create a slab cache for nfs_direct_req structures

 *

 */

int nfs_init_directcache(void)

{

	nfs_direct_cachep = kmem_cache_create("nfs_direct_cache",

	return 0;

}

/**

 * nfs_init_directcache - destroy the slab cache for nfs_direct_req structures

 *

 */

void nfs_destroy_directcache(void)

{

	if (kmem_cache_destroy(nfs_direct_cachep))