Commit b6aeaded authored by Miklos Szeredi's avatar Miklos Szeredi Committed by Linus Torvalds
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[PATCH] FUSE - file operations



This patch adds the file operations of FUSE.

The following operations are added:

 o open
 o flush
 o release
 o fsync
 o readpage
 o commit_write
Signed-off-by: default avatarMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 9e6268db
......@@ -4,4 +4,4 @@
obj-$(CONFIG_FUSE_FS) += fuse.o
fuse-objs := dev.o dir.o inode.o
fuse-objs := dev.o dir.o file.o inode.o
......@@ -731,6 +731,7 @@ static struct inode_operations fuse_dir_inode_operations = {
};
static struct file_operations fuse_dir_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
.readdir = fuse_readdir,
.open = fuse_dir_open,
......
/*
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 int fuse_open(struct inode *inode, struct file *file)
{
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
struct fuse_open_in inarg;
struct fuse_open_out outarg;
struct fuse_file *ff;
int err;
/* Restarting the syscall is not allowed if O_CREAT and O_EXCL
are both set, because creation will fail on the restart */
int excl = (file->f_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL);
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) {
int err = fuse_do_getattr(inode);
if (err)
return err;
}
if (excl)
req = fuse_get_request_nonint(fc);
else
req = fuse_get_request(fc);
if (!req)
return excl ? -EINTR : -ERESTARTSYS;
err = -ENOMEM;
ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
if (!ff)
goto out_put_request;
ff->release_req = fuse_request_alloc();
if (!ff->release_req) {
kfree(ff);
goto out_put_request;
}
memset(&inarg, 0, sizeof(inarg));
inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
req->in.h.opcode = 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(outarg);
req->out.args[0].value = &outarg;
if (excl)
request_send_nonint(fc, req);
else
request_send(fc, req);
err = req->out.h.error;
if (!err)
invalidate_inode_pages(inode->i_mapping);
if (err) {
fuse_request_free(ff->release_req);
kfree(ff);
} else {
ff->fh = outarg.fh;
file->private_data = ff;
}
out_put_request:
fuse_put_request(fc, req);
return err;
}
static int fuse_release(struct inode *inode, struct file *file)
{
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
struct fuse_req *req = ff->release_req;
struct fuse_release_in *inarg = &req->misc.release_in;
inarg->fh = ff->fh;
inarg->flags = file->f_flags & ~O_EXCL;
req->in.h.opcode = FUSE_RELEASE;
req->in.h.nodeid = get_node_id(inode);
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);
kfree(ff);
/* Return value is ignored by VFS */
return 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 (fc->no_flush)
return 0;
req = fuse_get_request_nonint(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_nonint(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {
fc->no_flush = 1;
err = 0;
}
return err;
}
static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
{
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 (fc->no_fsync)
return 0;
req = fuse_get_request(fc);
if (!req)
return -ERESTARTSYS;
memset(&inarg, 0, sizeof(inarg));
inarg.fh = ff->fh;
inarg.fsync_flags = datasync ? 1 : 0;
req->in.h.opcode = 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) {
fc->no_fsync = 1;
err = 0;
}
return err;
}
static ssize_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);
struct fuse_file *ff = file->private_data;
struct fuse_read_in inarg;
memset(&inarg, 0, sizeof(struct fuse_read_in));
inarg.fh = ff->fh;
inarg.offset = pos;
inarg.size = count;
req->in.h.opcode = FUSE_READ;
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;
request_send_nonint(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);
loff_t pos = (loff_t) page->index << PAGE_CACHE_SHIFT;
struct fuse_req *req = fuse_get_request_nonint(fc);
int err = -EINTR;
if (!req)
goto out;
req->out.page_zeroing = 1;
req->num_pages = 1;
req->pages[0] = page;
fuse_send_read(req, file, inode, pos, PAGE_CACHE_SIZE);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err)
SetPageUptodate(page);
out:
unlock_page(page);
return err;
}
static ssize_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_nonint(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;
ssize_t nres;
unsigned count = to - offset;
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
loff_t pos = ((loff_t) page->index << PAGE_CACHE_SHIFT) + offset;
struct fuse_req *req = fuse_get_request_nonint(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);
}
} else if (err == -EINTR || err == -EIO)
fuse_invalidate_attr(inode);
return err;
}
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 address_space_operations fuse_file_aops = {
.readpage = fuse_readpage,
.prepare_write = fuse_prepare_write,
.commit_write = fuse_commit_write,
.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;
}
......@@ -40,6 +40,15 @@ struct fuse_inode {
unsigned long i_time;
};
/** FUSE specific file data */
struct fuse_file {
/** Request reserved for flush and release */
struct fuse_req *release_req;
/** File handle used by userspace */
u64 fh;
};
/** One input argument of a request */
struct fuse_in_arg {
unsigned size;
......@@ -136,6 +145,7 @@ struct fuse_req {
/** Data for asynchronous requests */
union {
struct fuse_forget_in forget_in;
struct fuse_release_in release_in;
struct fuse_init_in_out init_in_out;
} misc;
......@@ -200,6 +210,12 @@ struct fuse_conn {
/** Connection failed (version mismatch) */
unsigned conn_error : 1;
/** Is fsync not implemented by fs? */
unsigned no_fsync : 1;
/** Is flush not implemented by fs? */
unsigned no_flush : 1;
/** Backing dev info */
struct backing_dev_info bdi;
};
......@@ -263,6 +279,11 @@ struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
unsigned long nodeid, u64 nlookup);
/**
* Initialise file operations on a regular file
*/
void fuse_init_file_inode(struct inode *inode);
/**
* Initialise inode operations on regular files and special files
*/
......
......@@ -124,6 +124,7 @@ static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
i_size_write(inode, attr->size);
if (S_ISREG(inode->i_mode)) {
fuse_init_common(inode);
fuse_init_file_inode(inode);
} else if (S_ISDIR(inode->i_mode))
fuse_init_dir(inode);
else if (S_ISLNK(inode->i_mode))
......@@ -137,6 +138,7 @@ static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
/* Don't let user create weird files */
inode->i_mode = S_IFREG;
fuse_init_common(inode);
fuse_init_file_inode(inode);
}
}
......
......@@ -74,7 +74,13 @@ enum fuse_opcode {
FUSE_RMDIR = 11,
FUSE_RENAME = 12,
FUSE_LINK = 13,
FUSE_OPEN = 14,
FUSE_READ = 15,
FUSE_WRITE = 16,
FUSE_STATFS = 17,
FUSE_RELEASE = 18,
FUSE_FSYNC = 20,
FUSE_FLUSH = 25,
FUSE_INIT = 26
};
......@@ -132,10 +138,51 @@ struct fuse_setattr_in {
struct fuse_attr attr;
};
struct fuse_open_in {
__u32 flags;
};
struct fuse_open_out {
__u64 fh;
__u32 open_flags;
};
struct fuse_release_in {
__u64 fh;
__u32 flags;
};
struct fuse_flush_in {
__u64 fh;
__u32 flush_flags;
};
struct fuse_read_in {
__u64 fh;
__u64 offset;
__u32 size;
};
struct fuse_write_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 write_flags;
};
struct fuse_write_out {
__u32 size;
};
struct fuse_statfs_out {
struct fuse_kstatfs st;
};
struct fuse_fsync_in {
__u64 fh;
__u32 fsync_flags;
};
struct fuse_init_in_out {
__u32 major;
__u32 minor;
......
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