path: root/fs/ceph/super.c

#include "ceph_debug.h"

#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/inet.h>
#include <linux/in6.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/parser.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/statfs.h>
#include <linux/string.h>

#include "decode.h"
#include "super.h"
#include "mon_client.h"
#include "auth.h"

/*
 * Ceph superblock operations
 *
 * Handle the basics of mounting, unmounting.
 */


/*
 * find filename portion of a path (/foo/bar/baz -> baz)
 */
const char *ceph_file_part(const char *s, int len)
{
	const char *e = s + len;

	while (e != s && *(e-1) != '/')
		e--;
	return e;
}


/*
 * super ops
 */
static void ceph_put_super(struct super_block *s)
{
	struct ceph_client *client = ceph_sb_to_client(s);

	dout("put_super\n");
	ceph_mdsc_close_sessions(&client->mdsc);

	/*
	 * ensure we release the bdi before put_anon_super releases
	 * the device name.
	 */
	if (s->s_bdi == &client->backing_dev_info) {
		bdi_unregister(&client->backing_dev_info);
		s->s_bdi = NULL;
	}

	return;
}

static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct ceph_client *client = ceph_inode_to_client(dentry->d_inode);
	struct ceph_monmap *monmap = client->monc.monmap;
	struct ceph_statfs st;
	u64 fsid;
	int err;

	dout("statfs\n");
	err = ceph_monc_do_statfs(&client->monc, &st);
	if (err < 0)
		return err;

	/* fill in kstatfs */
	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */

	/*
	 * express utilization in terms of large blocks to avoid
	 * overflow on 32-bit machines.
	 */
	buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
	buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
	buf->f_bfree = (le64_to_cpu(st.kb) - le64_to_cpu(st.kb_used)) >>
		(CEPH_BLOCK_SHIFT-10);
	buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);

	buf->f_files = le64_to_cpu(st.num_objects);
	buf->f_ffree = -1;
	buf->f_namelen = PATH_MAX;
	buf->f_frsize = PAGE_CACHE_SIZE;

	/* leave fsid little-endian, regardless of host endianness */
	fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
	buf->f_fsid.val[0] = fsid & 0xffffffff;
	buf->f_fsid.val[1] = fsid >> 32;

	return 0;
}


static int ceph_syncfs(struct super_block *sb, int wait)
{
	dout("sync_fs %d\n", wait);
	ceph_osdc_sync(&ceph_sb_to_client(sb)->osdc);
	ceph_mdsc_sync(&ceph_sb_to_client(sb)->mdsc);
	dout("sync_fs %d done\n", wait);
	return 0;
}

static int default_congestion_kb(void)
{
	int congestion_kb;

	/*
	 * Copied from NFS
	 *
	 * congestion size, scale with available memory.
	 *
	 *  64MB:    8192k
	 * 128MB:   11585k
	 * 256MB:   16384k
	 * 512MB:   23170k
	 *   1GB:   32768k
	 *   2GB:   46340k
	 *   4GB:   65536k
	 *   8GB:   92681k
	 *  16GB:  131072k
	 *
	 * This allows larger machines to have larger/more transfers.
	 * Limit the default to 256M
	 */
	congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
	if (congestion_kb > 256*1024)
		congestion_kb = 256*1024;

	return congestion_kb;
}

/**
 * ceph_show_options - Show mount options in /proc/mounts
 * @m: seq_file to write to
 * @mnt: mount descriptor
 */
static int ceph_show_options(struct seq_file *m, struct vfsmount