![Maxim Patlasov](/assets/img/avatar_default.png)
The bug was introduced with async_dio feature: trying to optimize short reads, we cut number-of-bytes-to-read to i_size boundary. Hence the following example: truncate --size=300 /mnt/file dd if=/mnt/file of=/dev/null iflag=direct led to FUSE_READ request of 300 bytes size. This turned out to be problem for userspace fuse implementations who rely on assumption that kernel fuse does not change alignment of request from client FS. The patch turns off the optimization if async_dio is disabled. And, if it's enabled, the patch fixes adjustment of number-of-bytes-to-read to preserve alignment. Note, that we cannot throw out short read optimization entirely because otherwise a direct read of a huge size issued on a tiny file would generate a huge amount of fuse requests and most of them would be ACKed by userspace with zero bytes read. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2575 lines
62 KiB
C
2575 lines
62 KiB
C
/*
|
|
FUSE: Filesystem in Userspace
|
|
Copyright (C) 2001-2008 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>
|
|
#include <linux/sched.h>
|
|
#include <linux/module.h>
|
|
#include <linux/compat.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/aio.h>
|
|
#include <linux/falloc.h>
|
|
|
|
static const struct file_operations fuse_direct_io_file_operations;
|
|
|
|
static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
|
|
int opcode, struct fuse_open_out *outargp)
|
|
{
|
|
struct fuse_open_in inarg;
|
|
struct fuse_req *req;
|
|
int err;
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
memset(&inarg, 0, sizeof(inarg));
|
|
inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
|
|
if (!fc->atomic_o_trunc)
|
|
inarg.flags &= ~O_TRUNC;
|
|
req->in.h.opcode = opcode;
|
|
req->in.h.nodeid = nodeid;
|
|
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;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
|
|
return err;
|
|
}
|
|
|
|
struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
|
|
{
|
|
struct fuse_file *ff;
|
|
|
|
ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
|
|
if (unlikely(!ff))
|
|
return NULL;
|
|
|
|
ff->fc = fc;
|
|
ff->reserved_req = fuse_request_alloc(0);
|
|
if (unlikely(!ff->reserved_req)) {
|
|
kfree(ff);
|
|
return NULL;
|
|
}
|
|
|
|
INIT_LIST_HEAD(&ff->write_entry);
|
|
atomic_set(&ff->count, 0);
|
|
RB_CLEAR_NODE(&ff->polled_node);
|
|
init_waitqueue_head(&ff->poll_wait);
|
|
|
|
spin_lock(&fc->lock);
|
|
ff->kh = ++fc->khctr;
|
|
spin_unlock(&fc->lock);
|
|
|
|
return ff;
|
|
}
|
|
|
|
void fuse_file_free(struct fuse_file *ff)
|
|
{
|
|
fuse_request_free(ff->reserved_req);
|
|
kfree(ff);
|
|
}
|
|
|
|
struct fuse_file *fuse_file_get(struct fuse_file *ff)
|
|
{
|
|
atomic_inc(&ff->count);
|
|
return ff;
|
|
}
|
|
|
|
static void fuse_release_async(struct work_struct *work)
|
|
{
|
|
struct fuse_req *req;
|
|
struct fuse_conn *fc;
|
|
struct path path;
|
|
|
|
req = container_of(work, struct fuse_req, misc.release.work);
|
|
path = req->misc.release.path;
|
|
fc = get_fuse_conn(path.dentry->d_inode);
|
|
|
|
fuse_put_request(fc, req);
|
|
path_put(&path);
|
|
}
|
|
|
|
static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
if (fc->destroy_req) {
|
|
/*
|
|
* If this is a fuseblk mount, then it's possible that
|
|
* releasing the path will result in releasing the
|
|
* super block and sending the DESTROY request. If
|
|
* the server is single threaded, this would hang.
|
|
* For this reason do the path_put() in a separate
|
|
* thread.
|
|
*/
|
|
atomic_inc(&req->count);
|
|
INIT_WORK(&req->misc.release.work, fuse_release_async);
|
|
schedule_work(&req->misc.release.work);
|
|
} else {
|
|
path_put(&req->misc.release.path);
|
|
}
|
|
}
|
|
|
|
static void fuse_file_put(struct fuse_file *ff, bool sync)
|
|
{
|
|
if (atomic_dec_and_test(&ff->count)) {
|
|
struct fuse_req *req = ff->reserved_req;
|
|
|
|
if (sync) {
|
|
req->background = 0;
|
|
fuse_request_send(ff->fc, req);
|
|
path_put(&req->misc.release.path);
|
|
fuse_put_request(ff->fc, req);
|
|
} else {
|
|
req->end = fuse_release_end;
|
|
req->background = 1;
|
|
fuse_request_send_background(ff->fc, req);
|
|
}
|
|
kfree(ff);
|
|
}
|
|
}
|
|
|
|
int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
|
|
bool isdir)
|
|
{
|
|
struct fuse_open_out outarg;
|
|
struct fuse_file *ff;
|
|
int err;
|
|
int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
|
|
|
|
ff = fuse_file_alloc(fc);
|
|
if (!ff)
|
|
return -ENOMEM;
|
|
|
|
err = fuse_send_open(fc, nodeid, file, opcode, &outarg);
|
|
if (err) {
|
|
fuse_file_free(ff);
|
|
return err;
|
|
}
|
|
|
|
if (isdir)
|
|
outarg.open_flags &= ~FOPEN_DIRECT_IO;
|
|
|
|
ff->fh = outarg.fh;
|
|
ff->nodeid = nodeid;
|
|
ff->open_flags = outarg.open_flags;
|
|
file->private_data = fuse_file_get(ff);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_do_open);
|
|
|
|
void fuse_finish_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
|
|
if (ff->open_flags & FOPEN_DIRECT_IO)
|
|
file->f_op = &fuse_direct_io_file_operations;
|
|
if (!(ff->open_flags & FOPEN_KEEP_CACHE))
|
|
invalidate_inode_pages2(inode->i_mapping);
|
|
if (ff->open_flags & FOPEN_NONSEEKABLE)
|
|
nonseekable_open(inode, file);
|
|
if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
spin_lock(&fc->lock);
|
|
fi->attr_version = ++fc->attr_version;
|
|
i_size_write(inode, 0);
|
|
spin_unlock(&fc->lock);
|
|
fuse_invalidate_attr(inode);
|
|
}
|
|
}
|
|
|
|
int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
int err;
|
|
|
|
err = generic_file_open(inode, file);
|
|
if (err)
|
|
return err;
|
|
|
|
err = fuse_do_open(fc, get_node_id(inode), file, isdir);
|
|
if (err)
|
|
return err;
|
|
|
|
fuse_finish_open(inode, file);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode)
|
|
{
|
|
struct fuse_conn *fc = ff->fc;
|
|
struct fuse_req *req = ff->reserved_req;
|
|
struct fuse_release_in *inarg = &req->misc.release.in;
|
|
|
|
spin_lock(&fc->lock);
|
|
list_del(&ff->write_entry);
|
|
if (!RB_EMPTY_NODE(&ff->polled_node))
|
|
rb_erase(&ff->polled_node, &fc->polled_files);
|
|
spin_unlock(&fc->lock);
|
|
|
|
wake_up_interruptible_all(&ff->poll_wait);
|
|
|
|
inarg->fh = ff->fh;
|
|
inarg->flags = flags;
|
|
req->in.h.opcode = opcode;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(struct fuse_release_in);
|
|
req->in.args[0].value = inarg;
|
|
}
|
|
|
|
void fuse_release_common(struct file *file, int opcode)
|
|
{
|
|
struct fuse_file *ff;
|
|
struct fuse_req *req;
|
|
|
|
ff = file->private_data;
|
|
if (unlikely(!ff))
|
|
return;
|
|
|
|
req = ff->reserved_req;
|
|
fuse_prepare_release(ff, file->f_flags, opcode);
|
|
|
|
if (ff->flock) {
|
|
struct fuse_release_in *inarg = &req->misc.release.in;
|
|
inarg->release_flags |= FUSE_RELEASE_FLOCK_UNLOCK;
|
|
inarg->lock_owner = fuse_lock_owner_id(ff->fc,
|
|
(fl_owner_t) file);
|
|
}
|
|
/* Hold vfsmount and dentry until release is finished */
|
|
path_get(&file->f_path);
|
|
req->misc.release.path = file->f_path;
|
|
|
|
/*
|
|
* Normally this will send the RELEASE request, however if
|
|
* some asynchronous READ or WRITE requests are outstanding,
|
|
* the sending will be delayed.
|
|
*
|
|
* Make the release synchronous if this is a fuseblk mount,
|
|
* synchronous RELEASE is allowed (and desirable) in this case
|
|
* because the server can be trusted not to screw up.
|
|
*/
|
|
fuse_file_put(ff, ff->fc->destroy_req != NULL);
|
|
}
|
|
|
|
static int fuse_open(struct inode *inode, struct file *file)
|
|
{
|
|
return fuse_open_common(inode, file, false);
|
|
}
|
|
|
|
static int fuse_release(struct inode *inode, struct file *file)
|
|
{
|
|
fuse_release_common(file, FUSE_RELEASE);
|
|
|
|
/* return value is ignored by VFS */
|
|
return 0;
|
|
}
|
|
|
|
void fuse_sync_release(struct fuse_file *ff, int flags)
|
|
{
|
|
WARN_ON(atomic_read(&ff->count) > 1);
|
|
fuse_prepare_release(ff, flags, FUSE_RELEASE);
|
|
ff->reserved_req->force = 1;
|
|
ff->reserved_req->background = 0;
|
|
fuse_request_send(ff->fc, ff->reserved_req);
|
|
fuse_put_request(ff->fc, ff->reserved_req);
|
|
kfree(ff);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_sync_release);
|
|
|
|
/*
|
|
* Scramble the ID space with XTEA, so that the value of the files_struct
|
|
* pointer is not exposed to userspace.
|
|
*/
|
|
u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
|
|
{
|
|
u32 *k = fc->scramble_key;
|
|
u64 v = (unsigned long) id;
|
|
u32 v0 = v;
|
|
u32 v1 = v >> 32;
|
|
u32 sum = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < 32; i++) {
|
|
v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
|
|
sum += 0x9E3779B9;
|
|
v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
|
|
}
|
|
|
|
return (u64) v0 + ((u64) v1 << 32);
|
|
}
|
|
|
|
/*
|
|
* Check if page is under writeback
|
|
*
|
|
* This is currently done by walking the list of writepage requests
|
|
* for the inode, which can be pretty inefficient.
|
|
*/
|
|
static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
struct fuse_req *req;
|
|
bool found = false;
|
|
|
|
spin_lock(&fc->lock);
|
|
list_for_each_entry(req, &fi->writepages, writepages_entry) {
|
|
pgoff_t curr_index;
|
|
|
|
BUG_ON(req->inode != inode);
|
|
curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
|
|
if (curr_index == index) {
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock(&fc->lock);
|
|
|
|
return found;
|
|
}
|
|
|
|
/*
|
|
* Wait for page writeback to be completed.
|
|
*
|
|
* Since fuse doesn't rely on the VM writeback tracking, this has to
|
|
* use some other means.
|
|
*/
|
|
static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index)
|
|
{
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index));
|
|
return 0;
|
|
}
|
|
|
|
static int fuse_flush(struct file *file, fl_owner_t id)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
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_req_nofail_nopages(fc, file);
|
|
memset(&inarg, 0, sizeof(inarg));
|
|
inarg.fh = ff->fh;
|
|
inarg.lock_owner = fuse_lock_owner_id(fc, id);
|
|
req->in.h.opcode = FUSE_FLUSH;
|
|
req->in.h.nodeid = get_node_id(inode);
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(inarg);
|
|
req->in.args[0].value = &inarg;
|
|
req->force = 1;
|
|
fuse_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;
|
|
}
|
|
|
|
/*
|
|
* Wait for all pending writepages on the inode to finish.
|
|
*
|
|
* This is currently done by blocking further writes with FUSE_NOWRITE
|
|
* and waiting for all sent writes to complete.
|
|
*
|
|
* This must be called under i_mutex, otherwise the FUSE_NOWRITE usage
|
|
* could conflict with truncation.
|
|
*/
|
|
static void fuse_sync_writes(struct inode *inode)
|
|
{
|
|
fuse_set_nowrite(inode);
|
|
fuse_release_nowrite(inode);
|
|
}
|
|
|
|
int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
|
|
int datasync, int isdir)
|
|
{
|
|
struct inode *inode = file->f_mapping->host;
|
|
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;
|
|
|
|
err = filemap_write_and_wait_range(inode->i_mapping, start, end);
|
|
if (err)
|
|
return err;
|
|
|
|
if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
|
|
return 0;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
/*
|
|
* Start writeback against all dirty pages of the inode, then
|
|
* wait for all outstanding writes, before sending the FSYNC
|
|
* request.
|
|
*/
|
|
err = write_inode_now(inode, 0);
|
|
if (err)
|
|
goto out;
|
|
|
|
fuse_sync_writes(inode);
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req)) {
|
|
err = PTR_ERR(req);
|
|
goto out;
|
|
}
|
|
|
|
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->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(inarg);
|
|
req->in.args[0].value = &inarg;
|
|
fuse_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;
|
|
}
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return err;
|
|
}
|
|
|
|
static int fuse_fsync(struct file *file, loff_t start, loff_t end,
|
|
int datasync)
|
|
{
|
|
return fuse_fsync_common(file, start, end, datasync, 0);
|
|
}
|
|
|
|
void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos,
|
|
size_t count, int opcode)
|
|
{
|
|
struct fuse_read_in *inarg = &req->misc.read.in;
|
|
struct fuse_file *ff = file->private_data;
|
|
|
|
inarg->fh = ff->fh;
|
|
inarg->offset = pos;
|
|
inarg->size = count;
|
|
inarg->flags = file->f_flags;
|
|
req->in.h.opcode = opcode;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(struct fuse_read_in);
|
|
req->in.args[0].value = inarg;
|
|
req->out.argvar = 1;
|
|
req->out.numargs = 1;
|
|
req->out.args[0].size = count;
|
|
}
|
|
|
|
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);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* In case of short read, the caller sets 'pos' to the position of
|
|
* actual end of fuse request in IO request. Otherwise, if bytes_requested
|
|
* == bytes_transferred or rw == WRITE, the caller sets 'pos' to -1.
|
|
*
|
|
* An example:
|
|
* User requested DIO read of 64K. It was splitted into two 32K fuse requests,
|
|
* both submitted asynchronously. The first of them was ACKed by userspace as
|
|
* fully completed (req->out.args[0].size == 32K) resulting in pos == -1. The
|
|
* second request was ACKed as short, e.g. only 1K was read, resulting in
|
|
* pos == 33K.
|
|
*
|
|
* Thus, when all fuse requests are completed, the minimal non-negative 'pos'
|
|
* will be equal to the length of the longest contiguous fragment of
|
|
* transferred data starting from the beginning of IO request.
|
|
*/
|
|
static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
|
|
{
|
|
int left;
|
|
|
|
spin_lock(&io->lock);
|
|
if (err)
|
|
io->err = io->err ? : err;
|
|
else if (pos >= 0 && (io->bytes < 0 || pos < io->bytes))
|
|
io->bytes = pos;
|
|
|
|
left = --io->reqs;
|
|
spin_unlock(&io->lock);
|
|
|
|
if (!left) {
|
|
long res;
|
|
|
|
if (io->err)
|
|
res = io->err;
|
|
else if (io->bytes >= 0 && io->write)
|
|
res = -EIO;
|
|
else {
|
|
res = io->bytes < 0 ? io->size : io->bytes;
|
|
|
|
if (!is_sync_kiocb(io->iocb)) {
|
|
struct path *path = &io->iocb->ki_filp->f_path;
|
|
struct inode *inode = path->dentry->d_inode;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
spin_lock(&fc->lock);
|
|
fi->attr_version = ++fc->attr_version;
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
}
|
|
|
|
aio_complete(io->iocb, res, 0);
|
|
kfree(io);
|
|
}
|
|
}
|
|
|
|
static void fuse_aio_complete_req(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
struct fuse_io_priv *io = req->io;
|
|
ssize_t pos = -1;
|
|
|
|
fuse_release_user_pages(req, !io->write);
|
|
|
|
if (io->write) {
|
|
if (req->misc.write.in.size != req->misc.write.out.size)
|
|
pos = req->misc.write.in.offset - io->offset +
|
|
req->misc.write.out.size;
|
|
} else {
|
|
if (req->misc.read.in.size != req->out.args[0].size)
|
|
pos = req->misc.read.in.offset - io->offset +
|
|
req->out.args[0].size;
|
|
}
|
|
|
|
fuse_aio_complete(io, req->out.h.error, pos);
|
|
}
|
|
|
|
static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req,
|
|
size_t num_bytes, struct fuse_io_priv *io)
|
|
{
|
|
spin_lock(&io->lock);
|
|
io->size += num_bytes;
|
|
io->reqs++;
|
|
spin_unlock(&io->lock);
|
|
|
|
req->io = io;
|
|
req->end = fuse_aio_complete_req;
|
|
|
|
__fuse_get_request(req);
|
|
fuse_request_send_background(fc, req);
|
|
|
|
return num_bytes;
|
|
}
|
|
|
|
static size_t fuse_send_read(struct fuse_req *req, struct fuse_io_priv *io,
|
|
loff_t pos, size_t count, fl_owner_t owner)
|
|
{
|
|
struct file *file = io->file;
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
|
|
fuse_read_fill(req, file, pos, count, FUSE_READ);
|
|
if (owner != NULL) {
|
|
struct fuse_read_in *inarg = &req->misc.read.in;
|
|
|
|
inarg->read_flags |= FUSE_READ_LOCKOWNER;
|
|
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
|
|
}
|
|
|
|
if (io->async)
|
|
return fuse_async_req_send(fc, req, count, io);
|
|
|
|
fuse_request_send(fc, req);
|
|
return req->out.args[0].size;
|
|
}
|
|
|
|
static void fuse_read_update_size(struct inode *inode, loff_t size,
|
|
u64 attr_ver)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
spin_lock(&fc->lock);
|
|
if (attr_ver == fi->attr_version && size < inode->i_size) {
|
|
fi->attr_version = ++fc->attr_version;
|
|
i_size_write(inode, size);
|
|
}
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
|
|
static int fuse_readpage(struct file *file, struct page *page)
|
|
{
|
|
struct fuse_io_priv io = { .async = 0, .file = file };
|
|
struct inode *inode = page->mapping->host;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_req *req;
|
|
size_t num_read;
|
|
loff_t pos = page_offset(page);
|
|
size_t count = PAGE_CACHE_SIZE;
|
|
u64 attr_ver;
|
|
int err;
|
|
|
|
err = -EIO;
|
|
if (is_bad_inode(inode))
|
|
goto out;
|
|
|
|
/*
|
|
* Page writeback can extend beyond the lifetime of the
|
|
* page-cache page, so make sure we read a properly synced
|
|
* page.
|
|
*/
|
|
fuse_wait_on_page_writeback(inode, page->index);
|
|
|
|
req = fuse_get_req(fc, 1);
|
|
err = PTR_ERR(req);
|
|
if (IS_ERR(req))
|
|
goto out;
|
|
|
|
attr_ver = fuse_get_attr_version(fc);
|
|
|
|
req->out.page_zeroing = 1;
|
|
req->out.argpages = 1;
|
|
req->num_pages = 1;
|
|
req->pages[0] = page;
|
|
req->page_descs[0].length = count;
|
|
num_read = fuse_send_read(req, &io, pos, count, NULL);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
|
|
if (!err) {
|
|
/*
|
|
* Short read means EOF. If file size is larger, truncate it
|
|
*/
|
|
if (num_read < count)
|
|
fuse_read_update_size(inode, pos + num_read, attr_ver);
|
|
|
|
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;
|
|
size_t count = req->misc.read.in.size;
|
|
size_t num_read = req->out.args[0].size;
|
|
struct address_space *mapping = NULL;
|
|
|
|
for (i = 0; mapping == NULL && i < req->num_pages; i++)
|
|
mapping = req->pages[i]->mapping;
|
|
|
|
if (mapping) {
|
|
struct inode *inode = mapping->host;
|
|
|
|
/*
|
|
* Short read means EOF. If file size is larger, truncate it
|
|
*/
|
|
if (!req->out.h.error && num_read < count) {
|
|
loff_t pos;
|
|
|
|
pos = page_offset(req->pages[0]) + num_read;
|
|
fuse_read_update_size(inode, pos,
|
|
req->misc.read.attr_ver);
|
|
}
|
|
fuse_invalidate_attr(inode); /* 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);
|
|
page_cache_release(page);
|
|
}
|
|
if (req->ff)
|
|
fuse_file_put(req->ff, false);
|
|
}
|
|
|
|
static void fuse_send_readpages(struct fuse_req *req, struct file *file)
|
|
{
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
loff_t pos = page_offset(req->pages[0]);
|
|
size_t count = req->num_pages << PAGE_CACHE_SHIFT;
|
|
|
|
req->out.argpages = 1;
|
|
req->out.page_zeroing = 1;
|
|
req->out.page_replace = 1;
|
|
fuse_read_fill(req, file, pos, count, FUSE_READ);
|
|
req->misc.read.attr_ver = fuse_get_attr_version(fc);
|
|
if (fc->async_read) {
|
|
req->ff = fuse_file_get(ff);
|
|
req->end = fuse_readpages_end;
|
|
fuse_request_send_background(fc, req);
|
|
} else {
|
|
fuse_request_send(fc, req);
|
|
fuse_readpages_end(fc, req);
|
|
fuse_put_request(fc, req);
|
|
}
|
|
}
|
|
|
|
struct fuse_fill_data {
|
|
struct fuse_req *req;
|
|
struct file *file;
|
|
struct inode *inode;
|
|
unsigned nr_pages;
|
|
};
|
|
|
|
static int fuse_readpages_fill(void *_data, struct page *page)
|
|
{
|
|
struct fuse_fill_data *data = _data;
|
|
struct fuse_req *req = data->req;
|
|
struct inode *inode = data->inode;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
|
|
fuse_wait_on_page_writeback(inode, page->index);
|
|
|
|
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)) {
|
|
int nr_alloc = min_t(unsigned, data->nr_pages,
|
|
FUSE_MAX_PAGES_PER_REQ);
|
|
fuse_send_readpages(req, data->file);
|
|
if (fc->async_read)
|
|
req = fuse_get_req_for_background(fc, nr_alloc);
|
|
else
|
|
req = fuse_get_req(fc, nr_alloc);
|
|
|
|
data->req = req;
|
|
if (IS_ERR(req)) {
|
|
unlock_page(page);
|
|
return PTR_ERR(req);
|
|
}
|
|
}
|
|
|
|
if (WARN_ON(req->num_pages >= req->max_pages)) {
|
|
fuse_put_request(fc, req);
|
|
return -EIO;
|
|
}
|
|
|
|
page_cache_get(page);
|
|
req->pages[req->num_pages] = page;
|
|
req->page_descs[req->num_pages].length = PAGE_SIZE;
|
|
req->num_pages++;
|
|
data->nr_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_fill_data data;
|
|
int err;
|
|
int nr_alloc = min_t(unsigned, nr_pages, FUSE_MAX_PAGES_PER_REQ);
|
|
|
|
err = -EIO;
|
|
if (is_bad_inode(inode))
|
|
goto out;
|
|
|
|
data.file = file;
|
|
data.inode = inode;
|
|
if (fc->async_read)
|
|
data.req = fuse_get_req_for_background(fc, nr_alloc);
|
|
else
|
|
data.req = fuse_get_req(fc, nr_alloc);
|
|
data.nr_pages = nr_pages;
|
|
err = PTR_ERR(data.req);
|
|
if (IS_ERR(data.req))
|
|
goto out;
|
|
|
|
err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
|
|
if (!err) {
|
|
if (data.req->num_pages)
|
|
fuse_send_readpages(data.req, file);
|
|
else
|
|
fuse_put_request(fc, data.req);
|
|
}
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos)
|
|
{
|
|
struct inode *inode = iocb->ki_filp->f_mapping->host;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
|
|
/*
|
|
* In auto invalidate mode, always update attributes on read.
|
|
* Otherwise, only update if we attempt to read past EOF (to ensure
|
|
* i_size is up to date).
|
|
*/
|
|
if (fc->auto_inval_data ||
|
|
(pos + iov_length(iov, nr_segs) > i_size_read(inode))) {
|
|
int err;
|
|
err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return generic_file_aio_read(iocb, iov, nr_segs, pos);
|
|
}
|
|
|
|
static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff,
|
|
loff_t pos, size_t count)
|
|
{
|
|
struct fuse_write_in *inarg = &req->misc.write.in;
|
|
struct fuse_write_out *outarg = &req->misc.write.out;
|
|
|
|
inarg->fh = ff->fh;
|
|
inarg->offset = pos;
|
|
inarg->size = count;
|
|
req->in.h.opcode = FUSE_WRITE;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
req->in.numargs = 2;
|
|
if (ff->fc->minor < 9)
|
|
req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE;
|
|
else
|
|
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;
|
|
}
|
|
|
|
static size_t fuse_send_write(struct fuse_req *req, struct fuse_io_priv *io,
|
|
loff_t pos, size_t count, fl_owner_t owner)
|
|
{
|
|
struct file *file = io->file;
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
struct fuse_write_in *inarg = &req->misc.write.in;
|
|
|
|
fuse_write_fill(req, ff, pos, count);
|
|
inarg->flags = file->f_flags;
|
|
if (owner != NULL) {
|
|
inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
|
|
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
|
|
}
|
|
|
|
if (io->async)
|
|
return fuse_async_req_send(fc, req, count, io);
|
|
|
|
fuse_request_send(fc, req);
|
|
return req->misc.write.out.size;
|
|
}
|
|
|
|
void fuse_write_update_size(struct inode *inode, loff_t pos)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
spin_lock(&fc->lock);
|
|
fi->attr_version = ++fc->attr_version;
|
|
if (pos > inode->i_size)
|
|
i_size_write(inode, pos);
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
|
|
static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
|
|
struct inode *inode, loff_t pos,
|
|
size_t count)
|
|
{
|
|
size_t res;
|
|
unsigned offset;
|
|
unsigned i;
|
|
struct fuse_io_priv io = { .async = 0, .file = file };
|
|
|
|
for (i = 0; i < req->num_pages; i++)
|
|
fuse_wait_on_page_writeback(inode, req->pages[i]->index);
|
|
|
|
res = fuse_send_write(req, &io, pos, count, NULL);
|
|
|
|
offset = req->page_descs[0].offset;
|
|
count = res;
|
|
for (i = 0; i < req->num_pages; i++) {
|
|
struct page *page = req->pages[i];
|
|
|
|
if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE)
|
|
SetPageUptodate(page);
|
|
|
|
if (count > PAGE_CACHE_SIZE - offset)
|
|
count -= PAGE_CACHE_SIZE - offset;
|
|
else
|
|
count = 0;
|
|
offset = 0;
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
static ssize_t fuse_fill_write_pages(struct fuse_req *req,
|
|
struct address_space *mapping,
|
|
struct iov_iter *ii, loff_t pos)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(mapping->host);
|
|
unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
size_t count = 0;
|
|
int err;
|
|
|
|
req->in.argpages = 1;
|
|
req->page_descs[0].offset = offset;
|
|
|
|
do {
|
|
size_t tmp;
|
|
struct page *page;
|
|
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
|
|
size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset,
|
|
iov_iter_count(ii));
|
|
|
|
bytes = min_t(size_t, bytes, fc->max_write - count);
|
|
|
|
again:
|
|
err = -EFAULT;
|
|
if (iov_iter_fault_in_readable(ii, bytes))
|
|
break;
|
|
|
|
err = -ENOMEM;
|
|
page = grab_cache_page_write_begin(mapping, index, 0);
|
|
if (!page)
|
|
break;
|
|
|
|
if (mapping_writably_mapped(mapping))
|
|
flush_dcache_page(page);
|
|
|
|
pagefault_disable();
|
|
tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
|
|
pagefault_enable();
|
|
flush_dcache_page(page);
|
|
|
|
mark_page_accessed(page);
|
|
|
|
if (!tmp) {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
bytes = min(bytes, iov_iter_single_seg_count(ii));
|
|
goto again;
|
|
}
|
|
|
|
err = 0;
|
|
req->pages[req->num_pages] = page;
|
|
req->page_descs[req->num_pages].length = tmp;
|
|
req->num_pages++;
|
|
|
|
iov_iter_advance(ii, tmp);
|
|
count += tmp;
|
|
pos += tmp;
|
|
offset += tmp;
|
|
if (offset == PAGE_CACHE_SIZE)
|
|
offset = 0;
|
|
|
|
if (!fc->big_writes)
|
|
break;
|
|
} while (iov_iter_count(ii) && count < fc->max_write &&
|
|
req->num_pages < req->max_pages && offset == 0);
|
|
|
|
return count > 0 ? count : err;
|
|
}
|
|
|
|
static inline unsigned fuse_wr_pages(loff_t pos, size_t len)
|
|
{
|
|
return min_t(unsigned,
|
|
((pos + len - 1) >> PAGE_CACHE_SHIFT) -
|
|
(pos >> PAGE_CACHE_SHIFT) + 1,
|
|
FUSE_MAX_PAGES_PER_REQ);
|
|
}
|
|
|
|
static ssize_t fuse_perform_write(struct file *file,
|
|
struct address_space *mapping,
|
|
struct iov_iter *ii, loff_t pos)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
int err = 0;
|
|
ssize_t res = 0;
|
|
|
|
if (is_bad_inode(inode))
|
|
return -EIO;
|
|
|
|
do {
|
|
struct fuse_req *req;
|
|
ssize_t count;
|
|
unsigned nr_pages = fuse_wr_pages(pos, iov_iter_count(ii));
|
|
|
|
req = fuse_get_req(fc, nr_pages);
|
|
if (IS_ERR(req)) {
|
|
err = PTR_ERR(req);
|
|
break;
|
|
}
|
|
|
|
count = fuse_fill_write_pages(req, mapping, ii, pos);
|
|
if (count <= 0) {
|
|
err = count;
|
|
} else {
|
|
size_t num_written;
|
|
|
|
num_written = fuse_send_write_pages(req, file, inode,
|
|
pos, count);
|
|
err = req->out.h.error;
|
|
if (!err) {
|
|
res += num_written;
|
|
pos += num_written;
|
|
|
|
/* break out of the loop on short write */
|
|
if (num_written != count)
|
|
err = -EIO;
|
|
}
|
|
}
|
|
fuse_put_request(fc, req);
|
|
} while (!err && iov_iter_count(ii));
|
|
|
|
if (res > 0)
|
|
fuse_write_update_size(inode, pos);
|
|
|
|
fuse_invalidate_attr(inode);
|
|
|
|
return res > 0 ? res : err;
|
|
}
|
|
|
|
static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct address_space *mapping = file->f_mapping;
|
|
size_t count = 0;
|
|
size_t ocount = 0;
|
|
ssize_t written = 0;
|
|
ssize_t written_buffered = 0;
|
|
struct inode *inode = mapping->host;
|
|
ssize_t err;
|
|
struct iov_iter i;
|
|
loff_t endbyte = 0;
|
|
|
|
WARN_ON(iocb->ki_pos != pos);
|
|
|
|
ocount = 0;
|
|
err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
|
|
if (err)
|
|
return err;
|
|
|
|
count = ocount;
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
/* We can write back this queue in page reclaim */
|
|
current->backing_dev_info = mapping->backing_dev_info;
|
|
|
|
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
|
|
if (err)
|
|
goto out;
|
|
|
|
if (count == 0)
|
|
goto out;
|
|
|
|
err = file_remove_suid(file);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = file_update_time(file);
|
|
if (err)
|
|
goto out;
|
|
|
|
if (file->f_flags & O_DIRECT) {
|
|
written = generic_file_direct_write(iocb, iov, &nr_segs,
|
|
pos, &iocb->ki_pos,
|
|
count, ocount);
|
|
if (written < 0 || written == count)
|
|
goto out;
|
|
|
|
pos += written;
|
|
count -= written;
|
|
|
|
iov_iter_init(&i, iov, nr_segs, count, written);
|
|
written_buffered = fuse_perform_write(file, mapping, &i, pos);
|
|
if (written_buffered < 0) {
|
|
err = written_buffered;
|
|
goto out;
|
|
}
|
|
endbyte = pos + written_buffered - 1;
|
|
|
|
err = filemap_write_and_wait_range(file->f_mapping, pos,
|
|
endbyte);
|
|
if (err)
|
|
goto out;
|
|
|
|
invalidate_mapping_pages(file->f_mapping,
|
|
pos >> PAGE_CACHE_SHIFT,
|
|
endbyte >> PAGE_CACHE_SHIFT);
|
|
|
|
written += written_buffered;
|
|
iocb->ki_pos = pos + written_buffered;
|
|
} else {
|
|
iov_iter_init(&i, iov, nr_segs, count, 0);
|
|
written = fuse_perform_write(file, mapping, &i, pos);
|
|
if (written >= 0)
|
|
iocb->ki_pos = pos + written;
|
|
}
|
|
out:
|
|
current->backing_dev_info = NULL;
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
return written ? written : err;
|
|
}
|
|
|
|
static inline void fuse_page_descs_length_init(struct fuse_req *req,
|
|
unsigned index, unsigned nr_pages)
|
|
{
|
|
int i;
|
|
|
|
for (i = index; i < index + nr_pages; i++)
|
|
req->page_descs[i].length = PAGE_SIZE -
|
|
req->page_descs[i].offset;
|
|
}
|
|
|
|
static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
|
|
{
|
|
return (unsigned long)ii->iov->iov_base + ii->iov_offset;
|
|
}
|
|
|
|
static inline size_t fuse_get_frag_size(const struct iov_iter *ii,
|
|
size_t max_size)
|
|
{
|
|
return min(iov_iter_single_seg_count(ii), max_size);
|
|
}
|
|
|
|
static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
|
|
size_t *nbytesp, int write)
|
|
{
|
|
size_t nbytes = 0; /* # bytes already packed in req */
|
|
|
|
/* Special case for kernel I/O: can copy directly into the buffer */
|
|
if (segment_eq(get_fs(), KERNEL_DS)) {
|
|
unsigned long user_addr = fuse_get_user_addr(ii);
|
|
size_t frag_size = fuse_get_frag_size(ii, *nbytesp);
|
|
|
|
if (write)
|
|
req->in.args[1].value = (void *) user_addr;
|
|
else
|
|
req->out.args[0].value = (void *) user_addr;
|
|
|
|
iov_iter_advance(ii, frag_size);
|
|
*nbytesp = frag_size;
|
|
return 0;
|
|
}
|
|
|
|
while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
|
|
unsigned npages;
|
|
unsigned long user_addr = fuse_get_user_addr(ii);
|
|
unsigned offset = user_addr & ~PAGE_MASK;
|
|
size_t frag_size = fuse_get_frag_size(ii, *nbytesp - nbytes);
|
|
int ret;
|
|
|
|
unsigned n = req->max_pages - req->num_pages;
|
|
frag_size = min_t(size_t, frag_size, n << PAGE_SHIFT);
|
|
|
|
npages = (frag_size + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
npages = clamp(npages, 1U, n);
|
|
|
|
ret = get_user_pages_fast(user_addr, npages, !write,
|
|
&req->pages[req->num_pages]);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
npages = ret;
|
|
frag_size = min_t(size_t, frag_size,
|
|
(npages << PAGE_SHIFT) - offset);
|
|
iov_iter_advance(ii, frag_size);
|
|
|
|
req->page_descs[req->num_pages].offset = offset;
|
|
fuse_page_descs_length_init(req, req->num_pages, npages);
|
|
|
|
req->num_pages += npages;
|
|
req->page_descs[req->num_pages - 1].length -=
|
|
(npages << PAGE_SHIFT) - offset - frag_size;
|
|
|
|
nbytes += frag_size;
|
|
}
|
|
|
|
if (write)
|
|
req->in.argpages = 1;
|
|
else
|
|
req->out.argpages = 1;
|
|
|
|
*nbytesp = nbytes;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int fuse_iter_npages(const struct iov_iter *ii_p)
|
|
{
|
|
struct iov_iter ii = *ii_p;
|
|
int npages = 0;
|
|
|
|
while (iov_iter_count(&ii) && npages < FUSE_MAX_PAGES_PER_REQ) {
|
|
unsigned long user_addr = fuse_get_user_addr(&ii);
|
|
unsigned offset = user_addr & ~PAGE_MASK;
|
|
size_t frag_size = iov_iter_single_seg_count(&ii);
|
|
|
|
npages += (frag_size + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
iov_iter_advance(&ii, frag_size);
|
|
}
|
|
|
|
return min(npages, FUSE_MAX_PAGES_PER_REQ);
|
|
}
|
|
|
|
ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
|
|
unsigned long nr_segs, size_t count, loff_t *ppos,
|
|
int write)
|
|
{
|
|
struct file *file = io->file;
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
size_t nmax = write ? fc->max_write : fc->max_read;
|
|
loff_t pos = *ppos;
|
|
ssize_t res = 0;
|
|
struct fuse_req *req;
|
|
struct iov_iter ii;
|
|
|
|
iov_iter_init(&ii, iov, nr_segs, count, 0);
|
|
|
|
if (io->async)
|
|
req = fuse_get_req_for_background(fc, fuse_iter_npages(&ii));
|
|
else
|
|
req = fuse_get_req(fc, fuse_iter_npages(&ii));
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
while (count) {
|
|
size_t nres;
|
|
fl_owner_t owner = current->files;
|
|
size_t nbytes = min(count, nmax);
|
|
int err = fuse_get_user_pages(req, &ii, &nbytes, write);
|
|
if (err) {
|
|
res = err;
|
|
break;
|
|
}
|
|
|
|
if (write)
|
|
nres = fuse_send_write(req, io, pos, nbytes, owner);
|
|
else
|
|
nres = fuse_send_read(req, io, pos, nbytes, owner);
|
|
|
|
if (!io->async)
|
|
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;
|
|
if (nres != nbytes)
|
|
break;
|
|
if (count) {
|
|
fuse_put_request(fc, req);
|
|
if (io->async)
|
|
req = fuse_get_req_for_background(fc,
|
|
fuse_iter_npages(&ii));
|
|
else
|
|
req = fuse_get_req(fc, fuse_iter_npages(&ii));
|
|
if (IS_ERR(req))
|
|
break;
|
|
}
|
|
}
|
|
if (!IS_ERR(req))
|
|
fuse_put_request(fc, req);
|
|
if (res > 0)
|
|
*ppos = pos;
|
|
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_direct_io);
|
|
|
|
static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
|
|
const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t *ppos,
|
|
size_t count)
|
|
{
|
|
ssize_t res;
|
|
struct file *file = io->file;
|
|
struct inode *inode = file_inode(file);
|
|
|
|
if (is_bad_inode(inode))
|
|
return -EIO;
|
|
|
|
res = fuse_direct_io(io, iov, nr_segs, count, ppos, 0);
|
|
|
|
fuse_invalidate_attr(inode);
|
|
|
|
return res;
|
|
}
|
|
|
|
static ssize_t fuse_direct_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct fuse_io_priv io = { .async = 0, .file = file };
|
|
struct iovec iov = { .iov_base = buf, .iov_len = count };
|
|
return __fuse_direct_read(&io, &iov, 1, ppos, count);
|
|
}
|
|
|
|
static ssize_t __fuse_direct_write(struct fuse_io_priv *io,
|
|
const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t *ppos)
|
|
{
|
|
struct file *file = io->file;
|
|
struct inode *inode = file_inode(file);
|
|
size_t count = iov_length(iov, nr_segs);
|
|
ssize_t res;
|
|
|
|
res = generic_write_checks(file, ppos, &count, 0);
|
|
if (!res)
|
|
res = fuse_direct_io(io, iov, nr_segs, count, ppos, 1);
|
|
|
|
fuse_invalidate_attr(inode);
|
|
|
|
return res;
|
|
}
|
|
|
|
static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
|
|
struct inode *inode = file_inode(file);
|
|
ssize_t res;
|
|
struct fuse_io_priv io = { .async = 0, .file = file };
|
|
|
|
if (is_bad_inode(inode))
|
|
return -EIO;
|
|
|
|
/* Don't allow parallel writes to the same file */
|
|
mutex_lock(&inode->i_mutex);
|
|
res = __fuse_direct_write(&io, &iov, 1, ppos);
|
|
if (res > 0)
|
|
fuse_write_update_size(inode, *ppos);
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
return res;
|
|
}
|
|
|
|
static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
__free_page(req->pages[0]);
|
|
fuse_file_put(req->ff, false);
|
|
}
|
|
|
|
static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
struct inode *inode = req->inode;
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
|
|
|
|
list_del(&req->writepages_entry);
|
|
dec_bdi_stat(bdi, BDI_WRITEBACK);
|
|
dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP);
|
|
bdi_writeout_inc(bdi);
|
|
wake_up(&fi->page_waitq);
|
|
}
|
|
|
|
/* Called under fc->lock, may release and reacquire it */
|
|
static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req)
|
|
__releases(fc->lock)
|
|
__acquires(fc->lock)
|
|
{
|
|
struct fuse_inode *fi = get_fuse_inode(req->inode);
|
|
loff_t size = i_size_read(req->inode);
|
|
struct fuse_write_in *inarg = &req->misc.write.in;
|
|
|
|
if (!fc->connected)
|
|
goto out_free;
|
|
|
|
if (inarg->offset + PAGE_CACHE_SIZE <= size) {
|
|
inarg->size = PAGE_CACHE_SIZE;
|
|
} else if (inarg->offset < size) {
|
|
inarg->size = size & (PAGE_CACHE_SIZE - 1);
|
|
} else {
|
|
/* Got truncated off completely */
|
|
goto out_free;
|
|
}
|
|
|
|
req->in.args[1].size = inarg->size;
|
|
fi->writectr++;
|
|
fuse_request_send_background_locked(fc, req);
|
|
return;
|
|
|
|
out_free:
|
|
fuse_writepage_finish(fc, req);
|
|
spin_unlock(&fc->lock);
|
|
fuse_writepage_free(fc, req);
|
|
fuse_put_request(fc, req);
|
|
spin_lock(&fc->lock);
|
|
}
|
|
|
|
/*
|
|
* If fi->writectr is positive (no truncate or fsync going on) send
|
|
* all queued writepage requests.
|
|
*
|
|
* Called with fc->lock
|
|
*/
|
|
void fuse_flush_writepages(struct inode *inode)
|
|
__releases(fc->lock)
|
|
__acquires(fc->lock)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
struct fuse_req *req;
|
|
|
|
while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {
|
|
req = list_entry(fi->queued_writes.next, struct fuse_req, list);
|
|
list_del_init(&req->list);
|
|
fuse_send_writepage(fc, req);
|
|
}
|
|
}
|
|
|
|
static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
struct inode *inode = req->inode;
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
|
|
mapping_set_error(inode->i_mapping, req->out.h.error);
|
|
spin_lock(&fc->lock);
|
|
fi->writectr--;
|
|
fuse_writepage_finish(fc, req);
|
|
spin_unlock(&fc->lock);
|
|
fuse_writepage_free(fc, req);
|
|
}
|
|
|
|
static int fuse_writepage_locked(struct page *page)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
struct fuse_req *req;
|
|
struct fuse_file *ff;
|
|
struct page *tmp_page;
|
|
|
|
set_page_writeback(page);
|
|
|
|
req = fuse_request_alloc_nofs(1);
|
|
if (!req)
|
|
goto err;
|
|
|
|
req->background = 1; /* writeback always goes to bg_queue */
|
|
tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
|
|
if (!tmp_page)
|
|
goto err_free;
|
|
|
|
spin_lock(&fc->lock);
|
|
BUG_ON(list_empty(&fi->write_files));
|
|
ff = list_entry(fi->write_files.next, struct fuse_file, write_entry);
|
|
req->ff = fuse_file_get(ff);
|
|
spin_unlock(&fc->lock);
|
|
|
|
fuse_write_fill(req, ff, page_offset(page), 0);
|
|
|
|
copy_highpage(tmp_page, page);
|
|
req->misc.write.in.write_flags |= FUSE_WRITE_CACHE;
|
|
req->in.argpages = 1;
|
|
req->num_pages = 1;
|
|
req->pages[0] = tmp_page;
|
|
req->page_descs[0].offset = 0;
|
|
req->page_descs[0].length = PAGE_SIZE;
|
|
req->end = fuse_writepage_end;
|
|
req->inode = inode;
|
|
|
|
inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK);
|
|
inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
|
|
end_page_writeback(page);
|
|
|
|
spin_lock(&fc->lock);
|
|
list_add(&req->writepages_entry, &fi->writepages);
|
|
list_add_tail(&req->list, &fi->queued_writes);
|
|
fuse_flush_writepages(inode);
|
|
spin_unlock(&fc->lock);
|
|
|
|
return 0;
|
|
|
|
err_free:
|
|
fuse_request_free(req);
|
|
err:
|
|
end_page_writeback(page);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int fuse_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int err;
|
|
|
|
err = fuse_writepage_locked(page);
|
|
unlock_page(page);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int fuse_launder_page(struct page *page)
|
|
{
|
|
int err = 0;
|
|
if (clear_page_dirty_for_io(page)) {
|
|
struct inode *inode = page->mapping->host;
|
|
err = fuse_writepage_locked(page);
|
|
if (!err)
|
|
fuse_wait_on_page_writeback(inode, page->index);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Write back dirty pages now, because there may not be any suitable
|
|
* open files later
|
|
*/
|
|
static void fuse_vma_close(struct vm_area_struct *vma)
|
|
{
|
|
filemap_write_and_wait(vma->vm_file->f_mapping);
|
|
}
|
|
|
|
/*
|
|
* Wait for writeback against this page to complete before allowing it
|
|
* to be marked dirty again, and hence written back again, possibly
|
|
* before the previous writepage completed.
|
|
*
|
|
* Block here, instead of in ->writepage(), so that the userspace fs
|
|
* can only block processes actually operating on the filesystem.
|
|
*
|
|
* Otherwise unprivileged userspace fs would be able to block
|
|
* unrelated:
|
|
*
|
|
* - page migration
|
|
* - sync(2)
|
|
* - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER
|
|
*/
|
|
static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
|
|
{
|
|
struct page *page = vmf->page;
|
|
/*
|
|
* Don't use page->mapping as it may become NULL from a
|
|
* concurrent truncate.
|
|
*/
|
|
struct inode *inode = vma->vm_file->f_mapping->host;
|
|
|
|
fuse_wait_on_page_writeback(inode, page->index);
|
|
return 0;
|
|
}
|
|
|
|
static const struct vm_operations_struct fuse_file_vm_ops = {
|
|
.close = fuse_vma_close,
|
|
.fault = filemap_fault,
|
|
.page_mkwrite = fuse_page_mkwrite,
|
|
.remap_pages = generic_file_remap_pages,
|
|
};
|
|
|
|
static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) {
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_inode *fi = get_fuse_inode(inode);
|
|
struct fuse_file *ff = file->private_data;
|
|
/*
|
|
* file may be written through mmap, so chain it onto the
|
|
* inodes's write_file list
|
|
*/
|
|
spin_lock(&fc->lock);
|
|
if (list_empty(&ff->write_entry))
|
|
list_add(&ff->write_entry, &fi->write_files);
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
file_accessed(file);
|
|
vma->vm_ops = &fuse_file_vm_ops;
|
|
return 0;
|
|
}
|
|
|
|
static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
/* Can't provide the coherency needed for MAP_SHARED */
|
|
if (vma->vm_flags & VM_MAYSHARE)
|
|
return -ENODEV;
|
|
|
|
invalidate_inode_pages2(file->f_mapping);
|
|
|
|
return generic_file_mmap(file, vma);
|
|
}
|
|
|
|
static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
|
|
struct file_lock *fl)
|
|
{
|
|
switch (ffl->type) {
|
|
case F_UNLCK:
|
|
break;
|
|
|
|
case F_RDLCK:
|
|
case F_WRLCK:
|
|
if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
|
|
ffl->end < ffl->start)
|
|
return -EIO;
|
|
|
|
fl->fl_start = ffl->start;
|
|
fl->fl_end = ffl->end;
|
|
fl->fl_pid = ffl->pid;
|
|
break;
|
|
|
|
default:
|
|
return -EIO;
|
|
}
|
|
fl->fl_type = ffl->type;
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_lk_fill(struct fuse_req *req, struct file *file,
|
|
const struct file_lock *fl, int opcode, pid_t pid,
|
|
int flock)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_lk_in *arg = &req->misc.lk_in;
|
|
|
|
arg->fh = ff->fh;
|
|
arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
|
|
arg->lk.start = fl->fl_start;
|
|
arg->lk.end = fl->fl_end;
|
|
arg->lk.type = fl->fl_type;
|
|
arg->lk.pid = pid;
|
|
if (flock)
|
|
arg->lk_flags |= FUSE_LK_FLOCK;
|
|
req->in.h.opcode = opcode;
|
|
req->in.h.nodeid = get_node_id(inode);
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(*arg);
|
|
req->in.args[0].value = arg;
|
|
}
|
|
|
|
static int fuse_getlk(struct file *file, struct file_lock *fl)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_req *req;
|
|
struct fuse_lk_out outarg;
|
|
int err;
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0);
|
|
req->out.numargs = 1;
|
|
req->out.args[0].size = sizeof(outarg);
|
|
req->out.args[0].value = &outarg;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
if (!err)
|
|
err = convert_fuse_file_lock(&outarg.lk, fl);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_req *req;
|
|
int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
|
|
pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
|
|
int err;
|
|
|
|
if (fl->fl_lmops && fl->fl_lmops->lm_grant) {
|
|
/* NLM needs asynchronous locks, which we don't support yet */
|
|
return -ENOLCK;
|
|
}
|
|
|
|
/* Unlock on close is handled by the flush method */
|
|
if (fl->fl_flags & FL_CLOSE)
|
|
return 0;
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
fuse_lk_fill(req, file, fl, opcode, pid, flock);
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
/* locking is restartable */
|
|
if (err == -EINTR)
|
|
err = -ERESTARTSYS;
|
|
fuse_put_request(fc, req);
|
|
return err;
|
|
}
|
|
|
|
static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
int err;
|
|
|
|
if (cmd == F_CANCELLK) {
|
|
err = 0;
|
|
} else if (cmd == F_GETLK) {
|
|
if (fc->no_lock) {
|
|
posix_test_lock(file, fl);
|
|
err = 0;
|
|
} else
|
|
err = fuse_getlk(file, fl);
|
|
} else {
|
|
if (fc->no_lock)
|
|
err = posix_lock_file(file, fl, NULL);
|
|
else
|
|
err = fuse_setlk(file, fl, 0);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
int err;
|
|
|
|
if (fc->no_flock) {
|
|
err = flock_lock_file_wait(file, fl);
|
|
} else {
|
|
struct fuse_file *ff = file->private_data;
|
|
|
|
/* emulate flock with POSIX locks */
|
|
fl->fl_owner = (fl_owner_t) file;
|
|
ff->flock = true;
|
|
err = fuse_setlk(file, fl, 1);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
struct fuse_req *req;
|
|
struct fuse_bmap_in inarg;
|
|
struct fuse_bmap_out outarg;
|
|
int err;
|
|
|
|
if (!inode->i_sb->s_bdev || fc->no_bmap)
|
|
return 0;
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req))
|
|
return 0;
|
|
|
|
memset(&inarg, 0, sizeof(inarg));
|
|
inarg.block = block;
|
|
inarg.blocksize = inode->i_sb->s_blocksize;
|
|
req->in.h.opcode = FUSE_BMAP;
|
|
req->in.h.nodeid = get_node_id(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(outarg);
|
|
req->out.args[0].value = &outarg;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
if (err == -ENOSYS)
|
|
fc->no_bmap = 1;
|
|
|
|
return err ? 0 : outarg.block;
|
|
}
|
|
|
|
static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence)
|
|
{
|
|
loff_t retval;
|
|
struct inode *inode = file_inode(file);
|
|
|
|
/* No i_mutex protection necessary for SEEK_CUR and SEEK_SET */
|
|
if (whence == SEEK_CUR || whence == SEEK_SET)
|
|
return generic_file_llseek(file, offset, whence);
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
retval = fuse_update_attributes(inode, NULL, file, NULL);
|
|
if (!retval)
|
|
retval = generic_file_llseek(file, offset, whence);
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
|
|
unsigned int nr_segs, size_t bytes, bool to_user)
|
|
{
|
|
struct iov_iter ii;
|
|
int page_idx = 0;
|
|
|
|
if (!bytes)
|
|
return 0;
|
|
|
|
iov_iter_init(&ii, iov, nr_segs, bytes, 0);
|
|
|
|
while (iov_iter_count(&ii)) {
|
|
struct page *page = pages[page_idx++];
|
|
size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii));
|
|
void *kaddr;
|
|
|
|
kaddr = kmap(page);
|
|
|
|
while (todo) {
|
|
char __user *uaddr = ii.iov->iov_base + ii.iov_offset;
|
|
size_t iov_len = ii.iov->iov_len - ii.iov_offset;
|
|
size_t copy = min(todo, iov_len);
|
|
size_t left;
|
|
|
|
if (!to_user)
|
|
left = copy_from_user(kaddr, uaddr, copy);
|
|
else
|
|
left = copy_to_user(uaddr, kaddr, copy);
|
|
|
|
if (unlikely(left))
|
|
return -EFAULT;
|
|
|
|
iov_iter_advance(&ii, copy);
|
|
todo -= copy;
|
|
kaddr += copy;
|
|
}
|
|
|
|
kunmap(page);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* CUSE servers compiled on 32bit broke on 64bit kernels because the
|
|
* ABI was defined to be 'struct iovec' which is different on 32bit
|
|
* and 64bit. Fortunately we can determine which structure the server
|
|
* used from the size of the reply.
|
|
*/
|
|
static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
|
|
size_t transferred, unsigned count,
|
|
bool is_compat)
|
|
{
|
|
#ifdef CONFIG_COMPAT
|
|
if (count * sizeof(struct compat_iovec) == transferred) {
|
|
struct compat_iovec *ciov = src;
|
|
unsigned i;
|
|
|
|
/*
|
|
* With this interface a 32bit server cannot support
|
|
* non-compat (i.e. ones coming from 64bit apps) ioctl
|
|
* requests
|
|
*/
|
|
if (!is_compat)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
dst[i].iov_base = compat_ptr(ciov[i].iov_base);
|
|
dst[i].iov_len = ciov[i].iov_len;
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
if (count * sizeof(struct iovec) != transferred)
|
|
return -EIO;
|
|
|
|
memcpy(dst, src, transferred);
|
|
return 0;
|
|
}
|
|
|
|
/* Make sure iov_length() won't overflow */
|
|
static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count)
|
|
{
|
|
size_t n;
|
|
u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT;
|
|
|
|
for (n = 0; n < count; n++, iov++) {
|
|
if (iov->iov_len > (size_t) max)
|
|
return -ENOMEM;
|
|
max -= iov->iov_len;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
|
|
void *src, size_t transferred, unsigned count,
|
|
bool is_compat)
|
|
{
|
|
unsigned i;
|
|
struct fuse_ioctl_iovec *fiov = src;
|
|
|
|
if (fc->minor < 16) {
|
|
return fuse_copy_ioctl_iovec_old(dst, src, transferred,
|
|
count, is_compat);
|
|
}
|
|
|
|
if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
|
|
return -EIO;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
/* Did the server supply an inappropriate value? */
|
|
if (fiov[i].base != (unsigned long) fiov[i].base ||
|
|
fiov[i].len != (unsigned long) fiov[i].len)
|
|
return -EIO;
|
|
|
|
dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
|
|
dst[i].iov_len = (size_t) fiov[i].len;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (is_compat &&
|
|
(ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
|
|
(compat_size_t) dst[i].iov_len != fiov[i].len))
|
|
return -EIO;
|
|
#endif
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* For ioctls, there is no generic way to determine how much memory
|
|
* needs to be read and/or written. Furthermore, ioctls are allowed
|
|
* to dereference the passed pointer, so the parameter requires deep
|
|
* copying but FUSE has no idea whatsoever about what to copy in or
|
|
* out.
|
|
*
|
|
* This is solved by allowing FUSE server to retry ioctl with
|
|
* necessary in/out iovecs. Let's assume the ioctl implementation
|
|
* needs to read in the following structure.
|
|
*
|
|
* struct a {
|
|
* char *buf;
|
|
* size_t buflen;
|
|
* }
|
|
*
|
|
* On the first callout to FUSE server, inarg->in_size and
|
|
* inarg->out_size will be NULL; then, the server completes the ioctl
|
|
* with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
|
|
* the actual iov array to
|
|
*
|
|
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
|
|
*
|
|
* which tells FUSE to copy in the requested area and retry the ioctl.
|
|
* On the second round, the server has access to the structure and
|
|
* from that it can tell what to look for next, so on the invocation,
|
|
* it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
|
|
*
|
|
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
|
|
* { .iov_base = a.buf, .iov_len = a.buflen } }
|
|
*
|
|
* FUSE will copy both struct a and the pointed buffer from the
|
|
* process doing the ioctl and retry ioctl with both struct a and the
|
|
* buffer.
|
|
*
|
|
* This time, FUSE server has everything it needs and completes ioctl
|
|
* without FUSE_IOCTL_RETRY which finishes the ioctl call.
|
|
*
|
|
* Copying data out works the same way.
|
|
*
|
|
* Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
|
|
* automatically initializes in and out iovs by decoding @cmd with
|
|
* _IOC_* macros and the server is not allowed to request RETRY. This
|
|
* limits ioctl data transfers to well-formed ioctls and is the forced
|
|
* behavior for all FUSE servers.
|
|
*/
|
|
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
|
|
unsigned int flags)
|
|
{
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
struct fuse_ioctl_in inarg = {
|
|
.fh = ff->fh,
|
|
.cmd = cmd,
|
|
.arg = arg,
|
|
.flags = flags
|
|
};
|
|
struct fuse_ioctl_out outarg;
|
|
struct fuse_req *req = NULL;
|
|
struct page **pages = NULL;
|
|
struct iovec *iov_page = NULL;
|
|
struct iovec *in_iov = NULL, *out_iov = NULL;
|
|
unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
|
|
size_t in_size, out_size, transferred;
|
|
int err;
|
|
|
|
#if BITS_PER_LONG == 32
|
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
#else
|
|
if (flags & FUSE_IOCTL_COMPAT)
|
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
#endif
|
|
|
|
/* assume all the iovs returned by client always fits in a page */
|
|
BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
|
|
|
|
err = -ENOMEM;
|
|
pages = kcalloc(FUSE_MAX_PAGES_PER_REQ, sizeof(pages[0]), GFP_KERNEL);
|
|
iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
|
|
if (!pages || !iov_page)
|
|
goto out;
|
|
|
|
/*
|
|
* If restricted, initialize IO parameters as encoded in @cmd.
|
|
* RETRY from server is not allowed.
|
|
*/
|
|
if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
|
|
struct iovec *iov = iov_page;
|
|
|
|
iov->iov_base = (void __user *)arg;
|
|
iov->iov_len = _IOC_SIZE(cmd);
|
|
|
|
if (_IOC_DIR(cmd) & _IOC_WRITE) {
|
|
in_iov = iov;
|
|
in_iovs = 1;
|
|
}
|
|
|
|
if (_IOC_DIR(cmd) & _IOC_READ) {
|
|
out_iov = iov;
|
|
out_iovs = 1;
|
|
}
|
|
}
|
|
|
|
retry:
|
|
inarg.in_size = in_size = iov_length(in_iov, in_iovs);
|
|
inarg.out_size = out_size = iov_length(out_iov, out_iovs);
|
|
|
|
/*
|
|
* Out data can be used either for actual out data or iovs,
|
|
* make sure there always is at least one page.
|
|
*/
|
|
out_size = max_t(size_t, out_size, PAGE_SIZE);
|
|
max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
|
|
|
|
/* make sure there are enough buffer pages and init request with them */
|
|
err = -ENOMEM;
|
|
if (max_pages > FUSE_MAX_PAGES_PER_REQ)
|
|
goto out;
|
|
while (num_pages < max_pages) {
|
|
pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
|
|
if (!pages[num_pages])
|
|
goto out;
|
|
num_pages++;
|
|
}
|
|
|
|
req = fuse_get_req(fc, num_pages);
|
|
if (IS_ERR(req)) {
|
|
err = PTR_ERR(req);
|
|
req = NULL;
|
|
goto out;
|
|
}
|
|
memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages);
|
|
req->num_pages = num_pages;
|
|
fuse_page_descs_length_init(req, 0, req->num_pages);
|
|
|
|
/* okay, let's send it to the client */
|
|
req->in.h.opcode = FUSE_IOCTL;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(inarg);
|
|
req->in.args[0].value = &inarg;
|
|
if (in_size) {
|
|
req->in.numargs++;
|
|
req->in.args[1].size = in_size;
|
|
req->in.argpages = 1;
|
|
|
|
err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size,
|
|
false);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
req->out.numargs = 2;
|
|
req->out.args[0].size = sizeof(outarg);
|
|
req->out.args[0].value = &outarg;
|
|
req->out.args[1].size = out_size;
|
|
req->out.argpages = 1;
|
|
req->out.argvar = 1;
|
|
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
transferred = req->out.args[1].size;
|
|
fuse_put_request(fc, req);
|
|
req = NULL;
|
|
if (err)
|
|
goto out;
|
|
|
|
/* did it ask for retry? */
|
|
if (outarg.flags & FUSE_IOCTL_RETRY) {
|
|
void *vaddr;
|
|
|
|
/* no retry if in restricted mode */
|
|
err = -EIO;
|
|
if (!(flags & FUSE_IOCTL_UNRESTRICTED))
|
|
goto out;
|
|
|
|
in_iovs = outarg.in_iovs;
|
|
out_iovs = outarg.out_iovs;
|
|
|
|
/*
|
|
* Make sure things are in boundary, separate checks
|
|
* are to protect against overflow.
|
|
*/
|
|
err = -ENOMEM;
|
|
if (in_iovs > FUSE_IOCTL_MAX_IOV ||
|
|
out_iovs > FUSE_IOCTL_MAX_IOV ||
|
|
in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
|
|
goto out;
|
|
|
|
vaddr = kmap_atomic(pages[0]);
|
|
err = fuse_copy_ioctl_iovec(fc, iov_page, vaddr,
|
|
transferred, in_iovs + out_iovs,
|
|
(flags & FUSE_IOCTL_COMPAT) != 0);
|
|
kunmap_atomic(vaddr);
|
|
if (err)
|
|
goto out;
|
|
|
|
in_iov = iov_page;
|
|
out_iov = in_iov + in_iovs;
|
|
|
|
err = fuse_verify_ioctl_iov(in_iov, in_iovs);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = fuse_verify_ioctl_iov(out_iov, out_iovs);
|
|
if (err)
|
|
goto out;
|
|
|
|
goto retry;
|
|
}
|
|
|
|
err = -EIO;
|
|
if (transferred > inarg.out_size)
|
|
goto out;
|
|
|
|
err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true);
|
|
out:
|
|
if (req)
|
|
fuse_put_request(fc, req);
|
|
free_page((unsigned long) iov_page);
|
|
while (num_pages)
|
|
__free_page(pages[--num_pages]);
|
|
kfree(pages);
|
|
|
|
return err ? err : outarg.result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_do_ioctl);
|
|
|
|
long fuse_ioctl_common(struct file *file, unsigned int cmd,
|
|
unsigned long arg, unsigned int flags)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
|
|
if (!fuse_allow_current_process(fc))
|
|
return -EACCES;
|
|
|
|
if (is_bad_inode(inode))
|
|
return -EIO;
|
|
|
|
return fuse_do_ioctl(file, cmd, arg, flags);
|
|
}
|
|
|
|
static long fuse_file_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
return fuse_ioctl_common(file, cmd, arg, 0);
|
|
}
|
|
|
|
static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
|
|
}
|
|
|
|
/*
|
|
* All files which have been polled are linked to RB tree
|
|
* fuse_conn->polled_files which is indexed by kh. Walk the tree and
|
|
* find the matching one.
|
|
*/
|
|
static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh,
|
|
struct rb_node **parent_out)
|
|
{
|
|
struct rb_node **link = &fc->polled_files.rb_node;
|
|
struct rb_node *last = NULL;
|
|
|
|
while (*link) {
|
|
struct fuse_file *ff;
|
|
|
|
last = *link;
|
|
ff = rb_entry(last, struct fuse_file, polled_node);
|
|
|
|
if (kh < ff->kh)
|
|
link = &last->rb_left;
|
|
else if (kh > ff->kh)
|
|
link = &last->rb_right;
|
|
else
|
|
return link;
|
|
}
|
|
|
|
if (parent_out)
|
|
*parent_out = last;
|
|
return link;
|
|
}
|
|
|
|
/*
|
|
* The file is about to be polled. Make sure it's on the polled_files
|
|
* RB tree. Note that files once added to the polled_files tree are
|
|
* not removed before the file is released. This is because a file
|
|
* polled once is likely to be polled again.
|
|
*/
|
|
static void fuse_register_polled_file(struct fuse_conn *fc,
|
|
struct fuse_file *ff)
|
|
{
|
|
spin_lock(&fc->lock);
|
|
if (RB_EMPTY_NODE(&ff->polled_node)) {
|
|
struct rb_node **link, *parent;
|
|
|
|
link = fuse_find_polled_node(fc, ff->kh, &parent);
|
|
BUG_ON(*link);
|
|
rb_link_node(&ff->polled_node, parent, link);
|
|
rb_insert_color(&ff->polled_node, &fc->polled_files);
|
|
}
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
|
|
unsigned fuse_file_poll(struct file *file, poll_table *wait)
|
|
{
|
|
struct fuse_file *ff = file->private_data;
|
|
struct fuse_conn *fc = ff->fc;
|
|
struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh };
|
|
struct fuse_poll_out outarg;
|
|
struct fuse_req *req;
|
|
int err;
|
|
|
|
if (fc->no_poll)
|
|
return DEFAULT_POLLMASK;
|
|
|
|
poll_wait(file, &ff->poll_wait, wait);
|
|
inarg.events = (__u32)poll_requested_events(wait);
|
|
|
|
/*
|
|
* Ask for notification iff there's someone waiting for it.
|
|
* The client may ignore the flag and always notify.
|
|
*/
|
|
if (waitqueue_active(&ff->poll_wait)) {
|
|
inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY;
|
|
fuse_register_polled_file(fc, ff);
|
|
}
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req))
|
|
return POLLERR;
|
|
|
|
req->in.h.opcode = FUSE_POLL;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
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(outarg);
|
|
req->out.args[0].value = &outarg;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
|
|
if (!err)
|
|
return outarg.revents;
|
|
if (err == -ENOSYS) {
|
|
fc->no_poll = 1;
|
|
return DEFAULT_POLLMASK;
|
|
}
|
|
return POLLERR;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_file_poll);
|
|
|
|
/*
|
|
* This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and
|
|
* wakes up the poll waiters.
|
|
*/
|
|
int fuse_notify_poll_wakeup(struct fuse_conn *fc,
|
|
struct fuse_notify_poll_wakeup_out *outarg)
|
|
{
|
|
u64 kh = outarg->kh;
|
|
struct rb_node **link;
|
|
|
|
spin_lock(&fc->lock);
|
|
|
|
link = fuse_find_polled_node(fc, kh, NULL);
|
|
if (*link) {
|
|
struct fuse_file *ff;
|
|
|
|
ff = rb_entry(*link, struct fuse_file, polled_node);
|
|
wake_up_interruptible_sync(&ff->poll_wait);
|
|
}
|
|
|
|
spin_unlock(&fc->lock);
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_do_truncate(struct file *file)
|
|
{
|
|
struct inode *inode = file->f_mapping->host;
|
|
struct iattr attr;
|
|
|
|
attr.ia_valid = ATTR_SIZE;
|
|
attr.ia_size = i_size_read(inode);
|
|
|
|
attr.ia_file = file;
|
|
attr.ia_valid |= ATTR_FILE;
|
|
|
|
fuse_do_setattr(inode, &attr, file);
|
|
}
|
|
|
|
static inline loff_t fuse_round_up(loff_t off)
|
|
{
|
|
return round_up(off, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
|
|
}
|
|
|
|
static ssize_t
|
|
fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
|
|
loff_t offset, unsigned long nr_segs)
|
|
{
|
|
ssize_t ret = 0;
|
|
struct file *file = iocb->ki_filp;
|
|
struct fuse_file *ff = file->private_data;
|
|
bool async_dio = ff->fc->async_dio;
|
|
loff_t pos = 0;
|
|
struct inode *inode;
|
|
loff_t i_size;
|
|
size_t count = iov_length(iov, nr_segs);
|
|
struct fuse_io_priv *io;
|
|
|
|
pos = offset;
|
|
inode = file->f_mapping->host;
|
|
i_size = i_size_read(inode);
|
|
|
|
/* optimization for short read */
|
|
if (async_dio && rw != WRITE && offset + count > i_size) {
|
|
if (offset >= i_size)
|
|
return 0;
|
|
count = min_t(loff_t, count, fuse_round_up(i_size - offset));
|
|
}
|
|
|
|
io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL);
|
|
if (!io)
|
|
return -ENOMEM;
|
|
spin_lock_init(&io->lock);
|
|
io->reqs = 1;
|
|
io->bytes = -1;
|
|
io->size = 0;
|
|
io->offset = offset;
|
|
io->write = (rw == WRITE);
|
|
io->err = 0;
|
|
io->file = file;
|
|
/*
|
|
* By default, we want to optimize all I/Os with async request
|
|
* submission to the client filesystem if supported.
|
|
*/
|
|
io->async = async_dio;
|
|
io->iocb = iocb;
|
|
|
|
/*
|
|
* We cannot asynchronously extend the size of a file. We have no method
|
|
* to wait on real async I/O requests, so we must submit this request
|
|
* synchronously.
|
|
*/
|
|
if (!is_sync_kiocb(iocb) && (offset + count > i_size) && rw == WRITE)
|
|
io->async = false;
|
|
|
|
if (rw == WRITE)
|
|
ret = __fuse_direct_write(io, iov, nr_segs, &pos);
|
|
else
|
|
ret = __fuse_direct_read(io, iov, nr_segs, &pos, count);
|
|
|
|
if (io->async) {
|
|
fuse_aio_complete(io, ret < 0 ? ret : 0, -1);
|
|
|
|
/* we have a non-extending, async request, so return */
|
|
if (!is_sync_kiocb(iocb))
|
|
return -EIOCBQUEUED;
|
|
|
|
ret = wait_on_sync_kiocb(iocb);
|
|
} else {
|
|
kfree(io);
|
|
}
|
|
|
|
if (rw == WRITE) {
|
|
if (ret > 0)
|
|
fuse_write_update_size(inode, pos);
|
|
else if (ret < 0 && offset + count > i_size)
|
|
fuse_do_truncate(file);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
|
|
loff_t length)
|
|
{
|
|
struct fuse_file *ff = file->private_data;
|
|
struct inode *inode = file->f_inode;
|
|
struct fuse_conn *fc = ff->fc;
|
|
struct fuse_req *req;
|
|
struct fuse_fallocate_in inarg = {
|
|
.fh = ff->fh,
|
|
.offset = offset,
|
|
.length = length,
|
|
.mode = mode
|
|
};
|
|
int err;
|
|
|
|
if (fc->no_fallocate)
|
|
return -EOPNOTSUPP;
|
|
|
|
if (mode & FALLOC_FL_PUNCH_HOLE) {
|
|
mutex_lock(&inode->i_mutex);
|
|
fuse_set_nowrite(inode);
|
|
}
|
|
|
|
req = fuse_get_req_nopages(fc);
|
|
if (IS_ERR(req)) {
|
|
err = PTR_ERR(req);
|
|
goto out;
|
|
}
|
|
|
|
req->in.h.opcode = FUSE_FALLOCATE;
|
|
req->in.h.nodeid = ff->nodeid;
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(inarg);
|
|
req->in.args[0].value = &inarg;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
if (err == -ENOSYS) {
|
|
fc->no_fallocate = 1;
|
|
err = -EOPNOTSUPP;
|
|
}
|
|
fuse_put_request(fc, req);
|
|
|
|
if (err)
|
|
goto out;
|
|
|
|
/* we could have extended the file */
|
|
if (!(mode & FALLOC_FL_KEEP_SIZE))
|
|
fuse_write_update_size(inode, offset + length);
|
|
|
|
if (mode & FALLOC_FL_PUNCH_HOLE)
|
|
truncate_pagecache_range(inode, offset, offset + length - 1);
|
|
|
|
fuse_invalidate_attr(inode);
|
|
|
|
out:
|
|
if (mode & FALLOC_FL_PUNCH_HOLE) {
|
|
fuse_release_nowrite(inode);
|
|
mutex_unlock(&inode->i_mutex);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations fuse_file_operations = {
|
|
.llseek = fuse_file_llseek,
|
|
.read = do_sync_read,
|
|
.aio_read = fuse_file_aio_read,
|
|
.write = do_sync_write,
|
|
.aio_write = fuse_file_aio_write,
|
|
.mmap = fuse_file_mmap,
|
|
.open = fuse_open,
|
|
.flush = fuse_flush,
|
|
.release = fuse_release,
|
|
.fsync = fuse_fsync,
|
|
.lock = fuse_file_lock,
|
|
.flock = fuse_file_flock,
|
|
.splice_read = generic_file_splice_read,
|
|
.unlocked_ioctl = fuse_file_ioctl,
|
|
.compat_ioctl = fuse_file_compat_ioctl,
|
|
.poll = fuse_file_poll,
|
|
.fallocate = fuse_file_fallocate,
|
|
};
|
|
|
|
static const struct file_operations fuse_direct_io_file_operations = {
|
|
.llseek = fuse_file_llseek,
|
|
.read = fuse_direct_read,
|
|
.write = fuse_direct_write,
|
|
.mmap = fuse_direct_mmap,
|
|
.open = fuse_open,
|
|
.flush = fuse_flush,
|
|
.release = fuse_release,
|
|
.fsync = fuse_fsync,
|
|
.lock = fuse_file_lock,
|
|
.flock = fuse_file_flock,
|
|
.unlocked_ioctl = fuse_file_ioctl,
|
|
.compat_ioctl = fuse_file_compat_ioctl,
|
|
.poll = fuse_file_poll,
|
|
.fallocate = fuse_file_fallocate,
|
|
/* no splice_read */
|
|
};
|
|
|
|
static const struct address_space_operations fuse_file_aops = {
|
|
.readpage = fuse_readpage,
|
|
.writepage = fuse_writepage,
|
|
.launder_page = fuse_launder_page,
|
|
.readpages = fuse_readpages,
|
|
.set_page_dirty = __set_page_dirty_nobuffers,
|
|
.bmap = fuse_bmap,
|
|
.direct_IO = fuse_direct_IO,
|
|
};
|
|
|
|
void fuse_init_file_inode(struct inode *inode)
|
|
{
|
|
inode->i_fop = &fuse_file_operations;
|
|
inode->i_data.a_ops = &fuse_file_aops;
|
|
}
|