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: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
index d085f07..76e307d 100644
--- a/fs/ceph/ioctl.c
+++ b/fs/ceph/ioctl.c
@@ -143,6 +143,27 @@
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 @@
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;
}
diff --git a/fs/ceph/ioctl.h b/fs/ceph/ioctl.h
index 25e4f1a..88451a3 100644
--- a/fs/ceph/ioctl.h
+++ b/fs/ceph/ioctl.h
@@ -37,4 +37,6 @@
#define CEPH_IOC_GET_DATALOC _IOWR(CEPH_IOCTL_MAGIC, 3, \
struct ceph_ioctl_dataloc)
+#define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4)
+
#endif