Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse updates from Miklos Szeredi:
 "This adds SEEK_HOLE and SEEK_DATA support in lseek"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: add support for SEEK_HOLE and SEEK_DATA in lseek
This commit is contained in:
Linus Torvalds 2016-01-21 12:14:24 -08:00
commit 5c89e9ea7e
3 changed files with 84 additions and 9 deletions

View file

@ -2231,20 +2231,77 @@ static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
return err ? 0 : outarg.block;
}
static loff_t fuse_lseek(struct file *file, loff_t offset, int whence)
{
struct inode *inode = file->f_mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
FUSE_ARGS(args);
struct fuse_lseek_in inarg = {
.fh = ff->fh,
.offset = offset,
.whence = whence
};
struct fuse_lseek_out outarg;
int err;
if (fc->no_lseek)
goto fallback;
args.in.h.opcode = FUSE_LSEEK;
args.in.h.nodeid = ff->nodeid;
args.in.numargs = 1;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
args.out.numargs = 1;
args.out.args[0].size = sizeof(outarg);
args.out.args[0].value = &outarg;
err = fuse_simple_request(fc, &args);
if (err) {
if (err == -ENOSYS) {
fc->no_lseek = 1;
goto fallback;
}
return err;
}
return vfs_setpos(file, outarg.offset, inode->i_sb->s_maxbytes);
fallback:
err = fuse_update_attributes(inode, NULL, file, NULL);
if (!err)
return generic_file_llseek(file, offset, whence);
else
return err;
}
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)
switch (whence) {
case SEEK_SET:
case SEEK_CUR:
/* No i_mutex protection necessary for SEEK_CUR and SEEK_SET */
retval = generic_file_llseek(file, offset, whence);
mutex_unlock(&inode->i_mutex);
break;
case SEEK_END:
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);
break;
case SEEK_HOLE:
case SEEK_DATA:
mutex_lock(&inode->i_mutex);
retval = fuse_lseek(file, offset, whence);
mutex_unlock(&inode->i_mutex);
break;
default:
retval = -EINVAL;
}
return retval;
}

View file

@ -605,6 +605,9 @@ struct fuse_conn {
/** Does the filesystem support asynchronous direct-IO submission? */
unsigned async_dio:1;
/** Is lseek not implemented by fs? */
unsigned no_lseek:1;
/** The number of requests waiting for completion */
atomic_t num_waiting;