[patch 11/12] fuse: add support for mandatory locking

Miklos Szeredi
2007-10-02T15:56:05Z

[-- Attachment #1: fuse_mandlock_support.patch --]
[-- Type: text/plain, Size: 6811 bytes --]

From: Miklos Szeredi <mszeredi@suse.cz>

For mandatory locking the userspace filesystem needs to know the lock
ownership for read, write and truncate operations.

This patch adds the necessary fields to the protocol.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---

Index: linux/fs/fuse/dir.c
===================================================================
--- linux.orig/fs/fuse/dir.c 2007-09-25 21:19:14.000000000 +0200
+++ linux/fs/fuse/dir.c 2007-09-25 21:19:15.000000000 +0200
@@ -1108,6 +1108,11 @@ static int fuse_do_setattr(struct dentry
inarg.valid |= FATTR_FH;
inarg.fh = ff->fh;
}
+ if (attr->ia_valid & ATTR_SIZE) {
+ /* For mandatory locking in truncate */
+ inarg.valid |= FATTR_LOCKOWNER;
+ inarg.lock_owner = fuse_lock_owner_id(fc, current->files);
+ }
req->in.h.opcode = FUSE_SETATTR;
req->in.h.nodeid = get_node_id(inode);
req->in.numargs = 1;
Index: linux/fs/fuse/file.c
===================================================================
--- linux.orig/fs/fuse/file.c 2007-09-25 21:19:15.000000000 +0200
+++ linux/fs/fuse/file.c 2007-09-25 21:19:15.000000000 +0200
@@ -189,7 +189,7 @@ static int fuse_release(struct inode *in
* Scramble the ID space with XTEA, so that the value of the files_struct
* pointer is not exposed to userspace.
*/
-static u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
+u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
{
u32 *k = fc->scramble_key;
u64 v = (unsigned long) id;
@@ -308,11 +308,19 @@ void fuse_read_fill(struct fuse_req *req
}

static size_t fuse_send_read(struct fuse_req *req, struct file *file,
- struct inode *inode, loff_t pos, size_t count)
+ struct inode *inode, loff_t pos, size_t count,
+ fl_owner_t owner)
{
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
+
fuse_read_fill(req, ff, inode, 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);
+ }
request_send(fc, req);
return req->out.args[0].size;
}
@@ -336,7 +344,8 @@ static int fuse_readpage(struct file *fi
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);
+ fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE,
+ NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err)
@@ -447,6 +456,7 @@ static void fuse_write_fill(struct fuse_
struct inode *inode, loff_t pos, size_t count,
int writepage)
{
+ struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_write_in *inarg = &req->misc.write.in;
struct fuse_write_out *outarg = &req->misc.write.out;

@@ -459,7 +469,10 @@ static void fuse_write_fill(struct fuse_
req->in.h.nodeid = get_node_id(inode);
req->in.argpages = 1;
req->in.numargs = 2;
- req->in.args[0].size = sizeof(struct fuse_write_in);
+ if (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;
@@ -468,10 +481,16 @@ static void fuse_write_fill(struct fuse_
}

static size_t fuse_send_write(struct fuse_req *req, struct file *file,
- struct inode *inode, loff_t pos, size_t count)
+ struct inode *inode, loff_t pos, size_t count,
+ fl_owner_t owner)
{
struct fuse_conn *fc = get_fuse_conn(inode);
fuse_write_fill(req, file->private_data, inode, pos, count, 0);
+ if (owner != NULL) {
+ struct fuse_write_in *inarg = &req->misc.write.in;
+ inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
+ inarg->lock_owner = fuse_lock_owner_id(fc, owner);
+ }
request_send(fc, req);
return req->misc.write.out.size;
}
@@ -508,7 +527,7 @@ static int fuse_buffered_write(struct fi
req->num_pages = 1;
req->pages[0] = page;
req->page_offset = offset;
- nres = fuse_send_write(req, file, inode, pos, count);
+ nres = fuse_send_write(req, file, inode, pos, count, NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err && !nres)
@@ -609,9 +628,11 @@ static ssize_t fuse_direct_io(struct fil
nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
nbytes = min(count, nbytes);
if (write)
- nres = fuse_send_write(req, file, inode, pos, nbytes);
+ nres = fuse_send_write(req, file, inode, pos, nbytes,
+ current->files);
else
- nres = fuse_send_read(req, file, inode, pos, nbytes);
+ nres = fuse_send_read(req, file, inode, pos, nbytes,
+ current->files);
fuse_release_user_pages(req, !write);
if (req->out.h.error) {
if (!res)
Index: linux/fs/fuse/fuse_i.h
===================================================================
--- linux.orig/fs/fuse/fuse_i.h 2007-09-25 21:19:15.000000000 +0200
+++ linux/fs/fuse/fuse_i.h 2007-09-25 21:19:15.000000000 +0200
@@ -591,3 +591,5 @@ int fuse_valid_type(int m);
* Is task allowed to perform filesystem operation?
*/
int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task);
+
+u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
Index: linux/include/linux/fuse.h
===================================================================
--- linux.orig/include/linux/fuse.h 2007-09-25 21:19:15.000000000 +0200
+++ linux/include/linux/fuse.h 2007-09-25 21:19:15.000000000 +0200
@@ -14,6 +14,7 @@
* 7.9:
* - new fuse_getattr_in input argument of GETATTR
* - add lk_flags in fuse_lk_in
+ * - add lock_owner field to fuse_setattr_in, fuse_read_in and fuse_write_in
*/

#include <asm/types.h>
@@ -86,6 +87,7 @@ struct fuse_file_lock {
#define FATTR_FH (1 << 6)
#define FATTR_ATIME_NOW (1 << 7)
#define FATTR_MTIME_NOW (1 << 8)
+#define FATTR_LOCKOWNER (1 << 9)

/**
* Flags returned by the OPEN request
@@ -123,8 +125,15 @@ struct fuse_file_lock {
* WRITE flags
*
* FUSE_WRITE_CACHE: delayed write from page cache, file handle is guessed
+ * FUSE_WRITE_LOCKOWNER: lock_owner field is valid
*/
#define FUSE_WRITE_CACHE (1 << 0)
+#define FUSE_WRITE_LOCKOWNER (1 << 1)
+
+/**
+ * Read flags
+ */
+#define FUSE_READ_LOCKOWNER (1 << 1)

enum fuse_opcode {
FUSE_LOOKUP = 1,
@@ -219,7 +228,7 @@ struct fuse_setattr_in {
__u32 padding;
__u64 fh;
__u64 size;
- __u64 unused1;
+ __u64 lock_owner;
__u64 atime;
__u64 mtime;
__u64 unused2;
@@ -262,14 +271,18 @@ struct fuse_read_in {
__u64 fh;
__u64 offset;
__u32 size;
- __u32 padding;
+ __u32 read_flags;
+ __u64 lock_owner;
};

+#define FUSE_COMPAT_WRITE_IN_SIZE 24
+
struct fuse_write_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 write_flags;
+ __u64 lock_owner;
};

struct fuse_write_out {

--