[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / fuse / file.c

/*
  FUSE: Filesystem in Userspace
  Copyright (C) 2001-2005  Miklos Szeredi <miklos@szeredi.hu>

  This program can be distributed under the terms of the GNU GPL.
  See the file COPYING.
*/

#include "fuse_i.h"

#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/kernel.h>

static struct file_operations fuse_direct_io_file_operations;

static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
			  struct fuse_open_out *outargp)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_open_in inarg;
	struct fuse_req *req;
	int err;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
	req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->out.numargs = 1;
	req->out.args[0].size = sizeof(*outargp);
	req->out.args[0].value = outargp;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);

	return err;
}

struct fuse_file *fuse_file_alloc(void)
{
	struct fuse_file *ff;
	ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
	if (ff) {
		ff->release_req = fuse_request_alloc();
		if (!ff->release_req) {
			kfree(ff);
			ff = NULL;
		}
	}
	return ff;
}

void fuse_file_free(struct fuse_file *ff)
{
	fuse_request_free(ff->release_req);
	kfree(ff);
}

void fuse_finish_open(struct inode *inode, struct file *file,
		      struct fuse_file *ff, struct fuse_open_out *outarg)
{
	if (outarg->open_flags & FOPEN_DIRECT_IO)
		file->f_op = &fuse_direct_io_file_operations;
	if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
		invalidate_inode_pages(inode->i_mapping);
	ff->fh = outarg->fh;
	file->private_data = ff;
}

int fuse_open_common(struct inode *inode, struct file *file, int isdir)
{
	struct fuse_open_out outarg;
	struct fuse_file *ff;
	int err;

	/* VFS checks this, but only _after_ ->open() */
	if (file->f_flags & O_DIRECT)
		return -EINVAL;

	err = generic_file_open(inode, file);
	if (err)
		return err;

	/* If opening the root node, no lookup has been performed on
	   it, so the attributes must be refreshed */
	if (get_node_id(inode) == FUSE_ROOT_ID) {
		err = fuse_do_getattr(inode);
		if (err)
		 	return err;
	}

	ff = fuse_file_alloc();
	if (!ff)
		return -ENOMEM;

	err = fuse_send_open(inode, file, isdir, &outarg);
	if (err)
		fuse_file_free(ff);
	else {
		if (isdir)
			outarg.open_flags &= ~FOPEN_DIRECT_IO;
		fuse_finish_open(inode, file, ff, &outarg);
	}

	return err;
}

/* Special case for failed iget in CREATE */
static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
{
	u64 nodeid = req->in.h.nodeid;
	fuse_reset_request(req);
	fuse_send_forget(fc, req, nodeid, 1);
}

void fuse_send_release(struct fuse_conn *fc, struct fuse_file *ff,
		       u64 nodeid, struct inode *inode, int flags, int isdir)
{
	struct fuse_req * req = ff->release_req;
	struct fuse_release_in *inarg = &req->misc.release_in;

	inarg->fh = ff->fh;
	inarg->flags = flags;
	req->in.h.opcode = isdir ? FUSE_RELEASEDIR : FUSE_RELEASE;
	req->in.h.nodeid = nodeid;
	req->inode = inode;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(struct fuse_release_in);
	req->in.args[0].value = inarg;
	request_send_background(fc, req);
	if (!inode)
		req->end = fuse_release_end;
	kfree(ff);
}

int fuse_release_common(struct inode *inode, struct file *file, int isdir)
{
	struct fuse_file *ff = file->private_data;
	if (ff) {
		struct fuse_conn *fc = get_fuse_conn(inode);
		u64 nodeid = get_node_id(inode);
		fuse_send_release(fc, ff, nodeid, inode, file->f_flags, isdir);
	}

	/* Return value is ignored by VFS */
	return 0;
}

static int fuse_open(struct inode *inode, struct file *file)
{
	return fuse_open_common(inode, file, 0);
}

static int fuse_release(struct inode *inode, struct file *file)
{
	return fuse_release_common(inode, file, 0);
}

static int fuse_flush(struct file *file)
{
	struct inode *inode = file->f_dentry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_file *ff = file->private_data;
	struct fuse_req *req;
	struct fuse_flush_in inarg;
	int err;

	if (is_bad_inode(inode))
		return -EIO;

	if (fc->no_flush)
		return 0;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.fh = ff->fh;
	req->in.h.opcode = FUSE_FLUSH;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->file = file;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_flush = 1;
		err = 0;
	}
	return err;
}

int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
		      int isdir)
{
	struct inode *inode = de->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_file *ff = file->private_data;
	struct fuse_req *req;
	struct fuse_fsync_in inarg;
	int err;

	if (is_bad_inode(inode))
		return -EIO;

	if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
		return 0;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.fh = ff->fh;
	inarg.fsync_flags = datasync ? 1 : 0;
	req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->file = file;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		if (isdir)
			fc->no_fsyncdir = 1;
		else
			fc->no_fsync = 1;
		err = 0;
	}
	return err;
}

static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
{
	return fuse_fsync_common(file, de, datasync, 0);
}

void fuse_read_fill(struct fuse_req *req, struct file *file,
		    struct inode *inode, loff_t pos, size_t count, int opcode)
{
	struct fuse_file *ff = file->private_data;
	struct fuse_read_in *inarg = &req->misc.read_in;

	inarg->fh = ff->fh;
	inarg->offset = pos;
	inarg->size = count;
	req->in.h.opcode = opcode;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->file = file;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(struct fuse_read_in);
	req->in.args[0].value = inarg;
	req->out.argpages = 1;
	req->out.argvar = 1;
	req->out.numargs = 1;
	req->out.args[0].size = count;
}

static size_t fuse_send_read(struct fuse_req *req, struct file *file,
			     struct inode *inode, loff_t pos, size_t count)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
	request_send(fc, req);
	return req->out.args[0].size;
}

static int fuse_readpage(struct file *file, struct page *page)
{
	struct inode *inode = page->mapping->host;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	int err;

	err = -EIO;
	if (is_bad_inode(inode))
		goto out;

	err = -EINTR;
	req = fuse_get_request(fc);
	if (!req)
		goto out;

	req->out.page_zeroing = 1;
	req->num_pages = 1;
	req->pages[0] = page;
	fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err)
		SetPageUptodate(page);
	fuse_invalidate_attr(inode); /* atime changed */
 out:
	unlock_page(page);
	return err;
}

static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
{
	int i;

	fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */

	for (i = 0; i < req->num_pages; i++) {
		struct page *page = req->pages[i];
		if (!req->out.h.error)
			SetPageUptodate(page);
		else
			SetPageError(page);
		unlock_page(page);
	}
	fuse_put_request(fc, req);
}

static void fuse_send_readpages(struct fuse_req *req, struct file *file,
				struct inode *inode)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	loff_t pos = page_offset(req->pages[0]);
	size_t count = req->num_pages << PAGE_CACHE_SHIFT;
	req->out.page_zeroing = 1;
	fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
	if (fc->async_read) {
		req->end = fuse_readpages_end;
		request_send_background(fc, req);
	} else {
		request_send(fc, req);
		fuse_readpages_end(fc, req);
	}
}

struct fuse_readpages_data {
	struct fuse_req *req;
	struct file *file;
	struct inode *inode;
};

static int fuse_readpages_fill(void *_data, struct page *page)
{
	struct fuse_readpages_data *data = _data;
	struct fuse_req *req = data->req;
	struct inode *inode = data->inode;
	struct fuse_conn *fc = get_fuse_conn(inode);

	if (req->num_pages &&
	    (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
	     (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
	     req->pages[req->num_pages - 1]->index + 1 != page->index)) {
		fuse_send_readpages(req, data->file, inode);
		data->req = req = fuse_get_request(fc);
		if (!req) {
			unlock_page(page);
			return -EINTR;
		}
	}
	req->pages[req->num_pages] = page;
	req->num_pages ++;
	return 0;
}

static int fuse_readpages(struct file *file, struct address_space *mapping,
			  struct list_head *pages, unsigned nr_pages)
{
	struct inode *inode = mapping->host;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_readpages_data data;
	int err;

	if (is_bad_inode(inode))
		return -EIO;

	data.file = file;
	data.inode = inode;
	data.req = fuse_get_request(fc);
	if (!data.req)
		return -EINTR;

	err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
	if (!err)
		fuse_send_readpages(data.req, file, inode);
	return err;
}

static size_t fuse_send_write(struct fuse_req *req, struct file *file,
			      struct inode *inode, loff_t pos, size_t count)
{
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_file *ff = file->private_data;
	struct fuse_write_in inarg;
	struct fuse_write_out outarg;

	memset(&inarg, 0, sizeof(struct fuse_write_in));
	inarg.fh = ff->fh;
	inarg.offset = pos;
	inarg.size = count;
	req->in.h.opcode = FUSE_WRITE;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->file = file;
	req->in.argpages = 1;
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(struct fuse_write_in);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = count;
	req->out.numargs = 1;
	req->out.args[0].size = sizeof(struct fuse_write_out);
	req->out.args[0].value = &outarg;
	request_send(fc, req);
	return outarg.size;
}

static int fuse_prepare_write(struct file *file, struct page *page,
			      unsigned offset, unsigned to)
{
	/* No op */
	return 0;
}

static int fuse_commit_write(struct file *file, struct page *page,
			     unsigned offset, unsigned to)
{
	int err;
	size_t nres;
	unsigned count = to - offset;
	struct inode *inode = page->mapping->host;
	struct fuse_conn *fc = get_fuse_conn(inode);
	loff_t pos = page_offset(page) + offset;
	struct fuse_req *req;

	if (is_bad_inode(inode))
		return -EIO;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	req->num_pages = 1;
	req->pages[0] = page;
	req->page_offset = offset;
	nres = fuse_send_write(req, file, inode, pos, count);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err && nres != count)
		err = -EIO;
	if (!err) {
		pos += count;
		if (pos > i_size_read(inode))
			i_size_write(inode, pos);

		if (offset == 0 && to == PAGE_CACHE_SIZE) {
			clear_page_dirty(page);
			SetPageUptodate(page);
		}
	}
	fuse_invalidate_attr(inode);
	return err;
}

static void fuse_release_user_pages(struct fuse_req *req, int write)
{
	unsigned i;

	for (i = 0; i < req->num_pages; i++) {
		struct page *page = req->pages[i];
		if (write)
			set_page_dirty_lock(page);
		put_page(page);
	}
}

static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
			       unsigned nbytes, int write)
{
	unsigned long user_addr = (unsigned long) buf;
	unsigned offset = user_addr & ~PAGE_MASK;
	int npages;

	/* This doesn't work with nfsd */
	if (!current->mm)
		return -EPERM;

	nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
	npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
	npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
	down_read(&current->mm->mmap_sem);
	npages = get_user_pages(current, current->mm, user_addr, npages, write,
				0, req->pages, NULL);
	up_read(&current->mm->mmap_sem);
	if (npages < 0)
		return npages;

	req->num_pages = npages;
	req->page_offset = offset;
	return 0;
}

static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
			      size_t count, loff_t *ppos, int write)
{
	struct inode *inode = file->f_dentry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	size_t nmax = write ? fc->max_write : fc->max_read;
	loff_t pos = *ppos;
	ssize_t res = 0;
	struct fuse_req *req;

	if (is_bad_inode(inode))
		return -EIO;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	while (count) {
		size_t nres;
		size_t nbytes = min(count, nmax);
		int err = fuse_get_user_pages(req, buf, nbytes, !write);
		if (err) {
			res = err;
			break;
		}
		nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
		nbytes = min(count, nbytes);
		if (write)
			nres = fuse_send_write(req, file, inode, pos, nbytes);
		else
			nres = fuse_send_read(req, file, inode, pos, nbytes);
		fuse_release_user_pages(req, !write);
		if (req->out.h.error) {
			if (!res)
				res = req->out.h.error;
			break;
		} else if (nres > nbytes) {
			res = -EIO;
			break;
		}
		count -= nres;
		res += nres;
		pos += nres;
		buf += nres;
		if (nres != nbytes)
			break;
		if (count)
			fuse_reset_request(req);
	}
	fuse_put_request(fc, req);
	if (res > 0) {
		if (write && pos > i_size_read(inode))
			i_size_write(inode, pos);
		*ppos = pos;
	}
	fuse_invalidate_attr(inode);

	return res;
}

static ssize_t fuse_direct_read(struct file *file, char __user *buf,
				     size_t count, loff_t *ppos)
{
	return fuse_direct_io(file, buf, count, ppos, 0);
}

static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
				 size_t count, loff_t *ppos)
{
	struct inode *inode = file->f_dentry->d_inode;
	ssize_t res;
	/* Don't allow parallel writes to the same file */
	mutex_lock(&inode->i_mutex);
	res = fuse_direct_io(file, buf, count, ppos, 1);
	mutex_unlock(&inode->i_mutex);
	return res;
}

static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
{
	if ((vma->vm_flags & VM_SHARED)) {
		if ((vma->vm_flags & VM_WRITE))
			return -ENODEV;
		else
			vma->vm_flags &= ~VM_MAYWRITE;
	}
	return generic_file_mmap(file, vma);
}

static int fuse_set_page_dirty(struct page *page)
{
	printk("fuse_set_page_dirty: should not happen\n");
	dump_stack();
	return 0;
}

static struct file_operations fuse_file_operations = {
	.llseek		= generic_file_llseek,
	.read		= generic_file_read,
	.write		= generic_file_write,
	.mmap		= fuse_file_mmap,
	.open		= fuse_open,
	.flush		= fuse_flush,
	.release	= fuse_release,
	.fsync		= fuse_fsync,
	.sendfile	= generic_file_sendfile,
};

static struct file_operations fuse_direct_io_file_operations = {
	.llseek		= generic_file_llseek,
	.read		= fuse_direct_read,
	.write		= fuse_direct_write,
	.open		= fuse_open,
	.flush		= fuse_flush,
	.release	= fuse_release,
	.fsync		= fuse_fsync,
	/* no mmap and sendfile */
};

static struct address_space_operations fuse_file_aops  = {
	.readpage	= fuse_readpage,
	.prepare_write	= fuse_prepare_write,
	.commit_write	= fuse_commit_write,
	.readpages	= fuse_readpages,
	.set_page_dirty	= fuse_set_page_dirty,
};

void fuse_init_file_inode(struct inode *inode)
{
	inode->i_fop = &fuse_file_operations;
	inode->i_data.a_ops = &fuse_file_aops;
}
Commit	Line	Data
b6aeaded MS	1	/*
	2	FUSE: Filesystem in Userspace
	3	Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
	4
	5	This program can be distributed under the terms of the GNU GPL.
	6	See the file COPYING.
	7	*/
	8
	9	#include "fuse_i.h"
	10
	11	#include <linux/pagemap.h>
	12	#include <linux/slab.h>
	13	#include <linux/kernel.h>
	14
45323fb7 MS	15	static struct file_operations fuse_direct_io_file_operations;
45323fb7 MS	16
fd72faac MS	17	static int fuse_send_open(struct inode inode, struct file file, int isdir,
fd72faac MS	18	struct fuse_open_out *outargp)
b6aeaded MS	19	{
b6aeaded MS	20	struct fuse_conn *fc = get_fuse_conn(inode);
b6aeaded	21	struct fuse_open_in inarg;
fd72faac MS	22	struct fuse_req *req;
	23	int err;
	24
	25	req = fuse_get_request(fc);
	26	if (!req)
	27	return -EINTR;
	28
	29	memset(&inarg, 0, sizeof(inarg));
	30	inarg.flags = file->f_flags & ~(O_CREAT \| O_EXCL \| O_NOCTTY \| O_TRUNC);
	31	req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
	32	req->in.h.nodeid = get_node_id(inode);
	33	req->inode = inode;
	34	req->in.numargs = 1;
	35	req->in.args[0].size = sizeof(inarg);
	36	req->in.args[0].value = &inarg;
	37	req->out.numargs = 1;
	38	req->out.args[0].size = sizeof(*outargp);
	39	req->out.args[0].value = outargp;
	40	request_send(fc, req);
	41	err = req->out.h.error;
	42	fuse_put_request(fc, req);
	43
	44	return err;
	45	}
	46
	47	struct fuse_file *fuse_file_alloc(void)
	48	{
	49	struct fuse_file *ff;
	50	ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
	51	if (ff) {
	52	ff->release_req = fuse_request_alloc();
	53	if (!ff->release_req) {
	54	kfree(ff);
	55	ff = NULL;
	56	}
	57	}
	58	return ff;
	59	}
	60
	61	void fuse_file_free(struct fuse_file *ff)
	62	{
	63	fuse_request_free(ff->release_req);
	64	kfree(ff);
	65	}
	66
	67	void fuse_finish_open(struct inode inode, struct file file,
	68	struct fuse_file ff, struct fuse_open_out outarg)
	69	{
	70	if (outarg->open_flags & FOPEN_DIRECT_IO)
	71	file->f_op = &fuse_direct_io_file_operations;
	72	if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
	73	invalidate_inode_pages(inode->i_mapping);
	74	ff->fh = outarg->fh;
	75	file->private_data = ff;
	76	}
	77
	78	int fuse_open_common(struct inode inode, struct file file, int isdir)
	79	{
b6aeaded MS	80	struct fuse_open_out outarg;
	81	struct fuse_file *ff;
	82	int err;
b6aeaded	83
dd190d06 MS	84	/* VFS checks this, but only _after_ ->open() */
	85	if (file->f_flags & O_DIRECT)
	86	return -EINVAL;
	87
b6aeaded MS	88	err = generic_file_open(inode, file);
	89	if (err)
	90	return err;
	91
	92	/* If opening the root node, no lookup has been performed on
	93	it, so the attributes must be refreshed */
	94	if (get_node_id(inode) == FUSE_ROOT_ID) {
fd72faac	95	err = fuse_do_getattr(inode);
b6aeaded MS	96	if (err)
	97	return err;
	98	}
	99
fd72faac	100	ff = fuse_file_alloc();
b6aeaded	101	if (!ff)
fd72faac	102	return -ENOMEM;
b6aeaded	103
fd72faac MS	104	err = fuse_send_open(inode, file, isdir, &outarg);
	105	if (err)
	106	fuse_file_free(ff);
	107	else {
	108	if (isdir)
	109	outarg.open_flags &= ~FOPEN_DIRECT_IO;
	110	fuse_finish_open(inode, file, ff, &outarg);
b6aeaded MS	111	}
b6aeaded MS	112
b6aeaded MS	113	return err;
	114	}
	115
64c6d8ed MS	116	/* Special case for failed iget in CREATE */
	117	static void fuse_release_end(struct fuse_conn fc, struct fuse_req req)
	118	{
	119	u64 nodeid = req->in.h.nodeid;
	120	fuse_reset_request(req);
	121	fuse_send_forget(fc, req, nodeid, 1);
	122	}
	123
fd72faac MS	124	void fuse_send_release(struct fuse_conn fc, struct fuse_file ff,
fd72faac MS	125	u64 nodeid, struct inode *inode, int flags, int isdir)
b6aeaded	126	{
fd72faac	127	struct fuse_req * req = ff->release_req;
b6aeaded MS	128	struct fuse_release_in *inarg = &req->misc.release_in;
	129
	130	inarg->fh = ff->fh;
fd72faac	131	inarg->flags = flags;
04730fef	132	req->in.h.opcode = isdir ? FUSE_RELEASEDIR : FUSE_RELEASE;
fd72faac	133	req->in.h.nodeid = nodeid;
b6aeaded MS	134	req->inode = inode;
	135	req->in.numargs = 1;
	136	req->in.args[0].size = sizeof(struct fuse_release_in);
	137	req->in.args[0].value = inarg;
	138	request_send_background(fc, req);
64c6d8ed MS	139	if (!inode)
64c6d8ed MS	140	req->end = fuse_release_end;
b6aeaded	141	kfree(ff);
fd72faac MS	142	}
	143
	144	int fuse_release_common(struct inode inode, struct file file, int isdir)
	145	{
	146	struct fuse_file *ff = file->private_data;
	147	if (ff) {
	148	struct fuse_conn *fc = get_fuse_conn(inode);
	149	u64 nodeid = get_node_id(inode);
	150	fuse_send_release(fc, ff, nodeid, inode, file->f_flags, isdir);
	151	}
b6aeaded MS	152
	153	/* Return value is ignored by VFS */
	154	return 0;
	155	}
	156
04730fef MS	157	static int fuse_open(struct inode inode, struct file file)
	158	{
	159	return fuse_open_common(inode, file, 0);
	160	}
	161
	162	static int fuse_release(struct inode inode, struct file file)
	163	{
	164	return fuse_release_common(inode, file, 0);
	165	}
	166
b6aeaded MS	167	static int fuse_flush(struct file *file)
	168	{
	169	struct inode *inode = file->f_dentry->d_inode;
	170	struct fuse_conn *fc = get_fuse_conn(inode);
	171	struct fuse_file *ff = file->private_data;
	172	struct fuse_req *req;
	173	struct fuse_flush_in inarg;
	174	int err;
	175
248d86e8 MS	176	if (is_bad_inode(inode))
	177	return -EIO;
	178
b6aeaded MS	179	if (fc->no_flush)
	180	return 0;
	181
7c352bdf	182	req = fuse_get_request(fc);
b6aeaded MS	183	if (!req)
	184	return -EINTR;
	185
	186	memset(&inarg, 0, sizeof(inarg));
	187	inarg.fh = ff->fh;
	188	req->in.h.opcode = FUSE_FLUSH;
	189	req->in.h.nodeid = get_node_id(inode);
	190	req->inode = inode;
	191	req->file = file;
	192	req->in.numargs = 1;
	193	req->in.args[0].size = sizeof(inarg);
	194	req->in.args[0].value = &inarg;
7c352bdf	195	request_send(fc, req);
b6aeaded MS	196	err = req->out.h.error;
	197	fuse_put_request(fc, req);
	198	if (err == -ENOSYS) {
	199	fc->no_flush = 1;
	200	err = 0;
	201	}
	202	return err;
	203	}
	204
82547981 MS	205	int fuse_fsync_common(struct file file, struct dentry de, int datasync,
82547981 MS	206	int isdir)
b6aeaded MS	207	{
	208	struct inode *inode = de->d_inode;
	209	struct fuse_conn *fc = get_fuse_conn(inode);
	210	struct fuse_file *ff = file->private_data;
	211	struct fuse_req *req;
	212	struct fuse_fsync_in inarg;
	213	int err;
	214
248d86e8 MS	215	if (is_bad_inode(inode))
	216	return -EIO;
	217
82547981	218	if ((!isdir && fc->no_fsync) \|\| (isdir && fc->no_fsyncdir))
b6aeaded MS	219	return 0;
	220
	221	req = fuse_get_request(fc);
	222	if (!req)
7c352bdf	223	return -EINTR;
b6aeaded MS	224
	225	memset(&inarg, 0, sizeof(inarg));
	226	inarg.fh = ff->fh;
	227	inarg.fsync_flags = datasync ? 1 : 0;
82547981	228	req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
b6aeaded MS	229	req->in.h.nodeid = get_node_id(inode);
	230	req->inode = inode;
	231	req->file = file;
	232	req->in.numargs = 1;
	233	req->in.args[0].size = sizeof(inarg);
	234	req->in.args[0].value = &inarg;
	235	request_send(fc, req);
	236	err = req->out.h.error;
	237	fuse_put_request(fc, req);
	238	if (err == -ENOSYS) {
82547981 MS	239	if (isdir)
	240	fc->no_fsyncdir = 1;
	241	else
	242	fc->no_fsync = 1;
b6aeaded MS	243	err = 0;
	244	}
	245	return err;
	246	}
	247
82547981 MS	248	static int fuse_fsync(struct file file, struct dentry de, int datasync)
	249	{
	250	return fuse_fsync_common(file, de, datasync, 0);
	251	}
	252
361b1eb5 MS	253	void fuse_read_fill(struct fuse_req req, struct file file,
361b1eb5 MS	254	struct inode *inode, loff_t pos, size_t count, int opcode)
b6aeaded	255	{
b6aeaded	256	struct fuse_file *ff = file->private_data;
361b1eb5	257	struct fuse_read_in *inarg = &req->misc.read_in;
b6aeaded	258
361b1eb5 MS	259	inarg->fh = ff->fh;
	260	inarg->offset = pos;
	261	inarg->size = count;
	262	req->in.h.opcode = opcode;
b6aeaded MS	263	req->in.h.nodeid = get_node_id(inode);
	264	req->inode = inode;
	265	req->file = file;
	266	req->in.numargs = 1;
	267	req->in.args[0].size = sizeof(struct fuse_read_in);
c1aa96a5	268	req->in.args[0].value = inarg;
b6aeaded MS	269	req->out.argpages = 1;
	270	req->out.argvar = 1;
	271	req->out.numargs = 1;
	272	req->out.args[0].size = count;
b6aeaded MS	273	}
b6aeaded MS	274
8bfc016d MS	275	static size_t fuse_send_read(struct fuse_req req, struct file file,
8bfc016d MS	276	struct inode *inode, loff_t pos, size_t count)
04730fef	277	{
361b1eb5 MS	278	struct fuse_conn *fc = get_fuse_conn(inode);
	279	fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
	280	request_send(fc, req);
	281	return req->out.args[0].size;
04730fef MS	282	}
04730fef MS	283
b6aeaded MS	284	static int fuse_readpage(struct file file, struct page page)
	285	{
	286	struct inode *inode = page->mapping->host;
	287	struct fuse_conn *fc = get_fuse_conn(inode);
248d86e8 MS	288	struct fuse_req *req;
	289	int err;
	290
	291	err = -EIO;
	292	if (is_bad_inode(inode))
	293	goto out;
	294
	295	err = -EINTR;
	296	req = fuse_get_request(fc);
b6aeaded MS	297	if (!req)
	298	goto out;
	299
	300	req->out.page_zeroing = 1;
	301	req->num_pages = 1;
	302	req->pages[0] = page;
4633a22e	303	fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
b6aeaded MS	304	err = req->out.h.error;
	305	fuse_put_request(fc, req);
	306	if (!err)
	307	SetPageUptodate(page);
b36c31ba	308	fuse_invalidate_attr(inode); /* atime changed */
b6aeaded MS	309	out:
	310	unlock_page(page);
	311	return err;
	312	}
	313
c1aa96a5	314	static void fuse_readpages_end(struct fuse_conn fc, struct fuse_req req)
db50b96c	315	{
c1aa96a5 MS	316	int i;
	317
	318	fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
	319
db50b96c MS	320	for (i = 0; i < req->num_pages; i++) {
	321	struct page *page = req->pages[i];
	322	if (!req->out.h.error)
	323	SetPageUptodate(page);
c1aa96a5 MS	324	else
c1aa96a5 MS	325	SetPageError(page);
db50b96c MS	326	unlock_page(page);
db50b96c MS	327	}
c1aa96a5 MS	328	fuse_put_request(fc, req);
	329	}
	330
	331	static void fuse_send_readpages(struct fuse_req req, struct file file,
	332	struct inode *inode)
	333	{
	334	struct fuse_conn *fc = get_fuse_conn(inode);
	335	loff_t pos = page_offset(req->pages[0]);
	336	size_t count = req->num_pages << PAGE_CACHE_SHIFT;
	337	req->out.page_zeroing = 1;
c1aa96a5	338	fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
9cd68455 MS	339	if (fc->async_read) {
	340	req->end = fuse_readpages_end;
	341	request_send_background(fc, req);
	342	} else {
	343	request_send(fc, req);
	344	fuse_readpages_end(fc, req);
	345	}
db50b96c MS	346	}
	347
	348	struct fuse_readpages_data {
	349	struct fuse_req *req;
	350	struct file *file;
	351	struct inode *inode;
	352	};
	353
	354	static int fuse_readpages_fill(void _data, struct page page)
	355	{
	356	struct fuse_readpages_data *data = _data;
	357	struct fuse_req *req = data->req;
	358	struct inode *inode = data->inode;
	359	struct fuse_conn *fc = get_fuse_conn(inode);
	360
	361	if (req->num_pages &&
	362	(req->num_pages == FUSE_MAX_PAGES_PER_REQ \|\|
	363	(req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read \|\|
	364	req->pages[req->num_pages - 1]->index + 1 != page->index)) {
c1aa96a5 MS	365	fuse_send_readpages(req, data->file, inode);
	366	data->req = req = fuse_get_request(fc);
	367	if (!req) {
db50b96c	368	unlock_page(page);
c1aa96a5	369	return -EINTR;
db50b96c	370	}
db50b96c MS	371	}
	372	req->pages[req->num_pages] = page;
	373	req->num_pages ++;
	374	return 0;
	375	}
	376
	377	static int fuse_readpages(struct file file, struct address_space mapping,
	378	struct list_head *pages, unsigned nr_pages)
	379	{
	380	struct inode *inode = mapping->host;
	381	struct fuse_conn *fc = get_fuse_conn(inode);
	382	struct fuse_readpages_data data;
	383	int err;
248d86e8 MS	384
	385	if (is_bad_inode(inode))
	386	return -EIO;
	387
db50b96c MS	388	data.file = file;
db50b96c MS	389	data.inode = inode;
7c352bdf	390	data.req = fuse_get_request(fc);
db50b96c MS	391	if (!data.req)
	392	return -EINTR;
	393
	394	err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
c1aa96a5 MS	395	if (!err)
c1aa96a5 MS	396	fuse_send_readpages(data.req, file, inode);
db50b96c MS	397	return err;
	398	}
	399
04730fef MS	400	static size_t fuse_send_write(struct fuse_req req, struct file file,
04730fef MS	401	struct inode *inode, loff_t pos, size_t count)
b6aeaded MS	402	{
	403	struct fuse_conn *fc = get_fuse_conn(inode);
	404	struct fuse_file *ff = file->private_data;
	405	struct fuse_write_in inarg;
	406	struct fuse_write_out outarg;
	407
	408	memset(&inarg, 0, sizeof(struct fuse_write_in));
	409	inarg.fh = ff->fh;
	410	inarg.offset = pos;
	411	inarg.size = count;
	412	req->in.h.opcode = FUSE_WRITE;
	413	req->in.h.nodeid = get_node_id(inode);
	414	req->inode = inode;
	415	req->file = file;
	416	req->in.argpages = 1;
	417	req->in.numargs = 2;
	418	req->in.args[0].size = sizeof(struct fuse_write_in);
	419	req->in.args[0].value = &inarg;
	420	req->in.args[1].size = count;
	421	req->out.numargs = 1;
	422	req->out.args[0].size = sizeof(struct fuse_write_out);
	423	req->out.args[0].value = &outarg;
7c352bdf	424	request_send(fc, req);
b6aeaded MS	425	return outarg.size;
	426	}
	427
	428	static int fuse_prepare_write(struct file file, struct page page,
	429	unsigned offset, unsigned to)
	430	{
	431	/* No op */
	432	return 0;
	433	}
	434
	435	static int fuse_commit_write(struct file file, struct page page,
	436	unsigned offset, unsigned to)
	437	{
	438	int err;
04730fef	439	size_t nres;
b6aeaded MS	440	unsigned count = to - offset;
	441	struct inode *inode = page->mapping->host;
	442	struct fuse_conn *fc = get_fuse_conn(inode);
4633a22e	443	loff_t pos = page_offset(page) + offset;
248d86e8 MS	444	struct fuse_req *req;
	445
	446	if (is_bad_inode(inode))
	447	return -EIO;
	448
	449	req = fuse_get_request(fc);
b6aeaded MS	450	if (!req)
	451	return -EINTR;
	452
	453	req->num_pages = 1;
	454	req->pages[0] = page;
	455	req->page_offset = offset;
	456	nres = fuse_send_write(req, file, inode, pos, count);
	457	err = req->out.h.error;
	458	fuse_put_request(fc, req);
	459	if (!err && nres != count)
	460	err = -EIO;
	461	if (!err) {
	462	pos += count;
	463	if (pos > i_size_read(inode))
	464	i_size_write(inode, pos);
	465
	466	if (offset == 0 && to == PAGE_CACHE_SIZE) {
	467	clear_page_dirty(page);
	468	SetPageUptodate(page);
	469	}
b36c31ba MS	470	}
b36c31ba MS	471	fuse_invalidate_attr(inode);
b6aeaded MS	472	return err;
	473	}
	474
413ef8cb MS	475	static void fuse_release_user_pages(struct fuse_req *req, int write)
	476	{
	477	unsigned i;
	478
	479	for (i = 0; i < req->num_pages; i++) {
	480	struct page *page = req->pages[i];
	481	if (write)
	482	set_page_dirty_lock(page);
	483	put_page(page);
	484	}
	485	}
	486
	487	static int fuse_get_user_pages(struct fuse_req req, const char __user buf,
	488	unsigned nbytes, int write)
	489	{
	490	unsigned long user_addr = (unsigned long) buf;
	491	unsigned offset = user_addr & ~PAGE_MASK;
	492	int npages;
	493
	494	/* This doesn't work with nfsd */
	495	if (!current->mm)
	496	return -EPERM;
	497
	498	nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
	499	npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
6ad84aca	500	npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
413ef8cb MS	501	down_read(&current->mm->mmap_sem);
	502	npages = get_user_pages(current, current->mm, user_addr, npages, write,
	503	0, req->pages, NULL);
	504	up_read(&current->mm->mmap_sem);
	505	if (npages < 0)
	506	return npages;
	507
	508	req->num_pages = npages;
	509	req->page_offset = offset;
	510	return 0;
	511	}
	512
	513	static ssize_t fuse_direct_io(struct file file, const char __user buf,
	514	size_t count, loff_t *ppos, int write)
	515	{
	516	struct inode *inode = file->f_dentry->d_inode;
	517	struct fuse_conn *fc = get_fuse_conn(inode);
	518	size_t nmax = write ? fc->max_write : fc->max_read;
	519	loff_t pos = *ppos;
	520	ssize_t res = 0;
248d86e8 MS	521	struct fuse_req *req;
	522
	523	if (is_bad_inode(inode))
	524	return -EIO;
	525
	526	req = fuse_get_request(fc);
413ef8cb	527	if (!req)
7c352bdf	528	return -EINTR;
413ef8cb MS	529
413ef8cb MS	530	while (count) {
413ef8cb MS	531	size_t nres;
	532	size_t nbytes = min(count, nmax);
	533	int err = fuse_get_user_pages(req, buf, nbytes, !write);
	534	if (err) {
	535	res = err;
	536	break;
	537	}
6ad84aca MS	538	nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
6ad84aca MS	539	nbytes = min(count, nbytes);
413ef8cb MS	540	if (write)
	541	nres = fuse_send_write(req, file, inode, pos, nbytes);
	542	else
	543	nres = fuse_send_read(req, file, inode, pos, nbytes);
	544	fuse_release_user_pages(req, !write);
	545	if (req->out.h.error) {
	546	if (!res)
	547	res = req->out.h.error;
	548	break;
	549	} else if (nres > nbytes) {
	550	res = -EIO;
	551	break;
	552	}
	553	count -= nres;
	554	res += nres;
	555	pos += nres;
	556	buf += nres;
	557	if (nres != nbytes)
	558	break;
	559	if (count)
	560	fuse_reset_request(req);
	561	}
	562	fuse_put_request(fc, req);
	563	if (res > 0) {
	564	if (write && pos > i_size_read(inode))
	565	i_size_write(inode, pos);
	566	*ppos = pos;
b36c31ba MS	567	}
b36c31ba MS	568	fuse_invalidate_attr(inode);
413ef8cb MS	569
	570	return res;
	571	}
	572
	573	static ssize_t fuse_direct_read(struct file file, char __user buf,
	574	size_t count, loff_t *ppos)
	575	{
	576	return fuse_direct_io(file, buf, count, ppos, 0);
	577	}
	578
	579	static ssize_t fuse_direct_write(struct file file, const char __user buf,
	580	size_t count, loff_t *ppos)
	581	{
	582	struct inode *inode = file->f_dentry->d_inode;
	583	ssize_t res;
	584	/* Don't allow parallel writes to the same file */
1b1dcc1b	585	mutex_lock(&inode->i_mutex);
413ef8cb	586	res = fuse_direct_io(file, buf, count, ppos, 1);
1b1dcc1b	587	mutex_unlock(&inode->i_mutex);
413ef8cb MS	588	return res;
	589	}
	590
b6aeaded MS	591	static int fuse_file_mmap(struct file file, struct vm_area_struct vma)
	592	{
	593	if ((vma->vm_flags & VM_SHARED)) {
	594	if ((vma->vm_flags & VM_WRITE))
	595	return -ENODEV;
	596	else
	597	vma->vm_flags &= ~VM_MAYWRITE;
	598	}
	599	return generic_file_mmap(file, vma);
	600	}
	601
	602	static int fuse_set_page_dirty(struct page *page)
	603	{
	604	printk("fuse_set_page_dirty: should not happen\n");
	605	dump_stack();
	606	return 0;
	607	}
	608
	609	static struct file_operations fuse_file_operations = {
	610	.llseek = generic_file_llseek,
	611	.read = generic_file_read,
	612	.write = generic_file_write,
	613	.mmap = fuse_file_mmap,
	614	.open = fuse_open,
	615	.flush = fuse_flush,
	616	.release = fuse_release,
	617	.fsync = fuse_fsync,
	618	.sendfile = generic_file_sendfile,
	619	};
	620
413ef8cb MS	621	static struct file_operations fuse_direct_io_file_operations = {
	622	.llseek = generic_file_llseek,
	623	.read = fuse_direct_read,
	624	.write = fuse_direct_write,
	625	.open = fuse_open,
	626	.flush = fuse_flush,
	627	.release = fuse_release,
	628	.fsync = fuse_fsync,
	629	/* no mmap and sendfile */
	630	};
	631
b6aeaded MS	632	static struct address_space_operations fuse_file_aops = {
	633	.readpage = fuse_readpage,
	634	.prepare_write = fuse_prepare_write,
	635	.commit_write = fuse_commit_write,
db50b96c	636	.readpages = fuse_readpages,
b6aeaded MS	637	.set_page_dirty = fuse_set_page_dirty,
	638	};
	639
	640	void fuse_init_file_inode(struct inode *inode)
	641	{
45323fb7 MS	642	inode->i_fop = &fuse_file_operations;
45323fb7 MS	643	inode->i_data.a_ops = &fuse_file_aops;
b6aeaded	644	}