Commit 8c6e9229 authored by Sage Weil's avatar Sage Weil
Browse files

ceph: add LAZYIO ioctl to mark a file description for lazy consistency 



Allow an application to mark a file descriptor for lazy file consistency
semantics, allowing buffered reads and writes when multiple clients are
accessing the same file.

Signed-off-by: default avatarSage Weil <sage@newdream.net>
parent 84d95092

fs/ceph/ioctl.c

+24 −0
Original line number Diff line number Diff line
@@ -143,6 +143,27 @@ static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg) 
	return 0;

}



static long ceph_ioctl_lazyio(struct file *file)

{

	struct ceph_file_info *fi = file->private_data;

	struct inode *inode = file->f_dentry->d_inode;

	struct ceph_inode_info *ci = ceph_inode(inode);



	if ((fi->fmode & CEPH_FILE_MODE_LAZY) == 0) {

		spin_lock(&inode->i_lock);

		ci->i_nr_by_mode[fi->fmode]--;

		fi->fmode |= CEPH_FILE_MODE_LAZY;

		ci->i_nr_by_mode[fi->fmode]++;

		spin_unlock(&inode->i_lock);

		dout("ioctl_layzio: file %p marked lazy\n", file);



		ceph_check_caps(ci, 0, NULL);

	} else {

		dout("ioctl_layzio: file %p already lazy\n", file);

	}

	return 0;

}



long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	dout("ioctl file %p cmd %u arg %lu\n", file, cmd, arg);
@@ -155,6 +176,9 @@ long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 


	case CEPH_IOC_GET_DATALOC:

		return ceph_ioctl_get_dataloc(file, (void __user *)arg);



	case CEPH_IOC_LAZYIO:

		return ceph_ioctl_lazyio(file);

	}

	return -ENOTTY;

}

fs/ceph/ioctl.h

+2 −0
Original line number Diff line number Diff line
@@ -37,4 +37,6 @@ struct ceph_ioctl_dataloc { 
#define CEPH_IOC_GET_DATALOC _IOWR(CEPH_IOCTL_MAGIC, 3,	\

				   struct ceph_ioctl_dataloc)



#define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4)



#endif