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>
This commit is contained in:
Sage Weil 2010-04-16 09:53:43 -07:00
parent 84d9509234
commit 8c6e9229fc
2 changed files with 26 additions and 0 deletions

View file

@ -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;
}

View file

@ -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