minix/servers/mfs/mount.c

191 lines
5.1 KiB
C

#include "fs.h"
#include <fcntl.h>
#include <string.h>
#include <minix/com.h>
#include <sys/stat.h>
#include "buf.h"
#include "inode.h"
#include "super.h"
#include "drivers.h"
#include <minix/vfsif.h>
/*===========================================================================*
* fs_readsuper *
*===========================================================================*/
PUBLIC int fs_readsuper()
{
/* This function reads the superblock of the partition, gets the root inode
* and sends back the details of them. Note, that the FS process does not
* know the index of the vmnt object which refers to it, whenever the pathname
* lookup leaves a partition an ELEAVEMOUNT error is transferred back
* so that the VFS knows that it has to find the vnode on which this FS
* process' partition is mounted on.
*/
struct super_block *xp, *sp;
struct inode *root_ip;
int r = OK;
fs_dev = fs_m_in.REQ_DEV;
/* Map the driver endpoint for this major */
driver_endpoints[(fs_dev >> MAJOR) & BYTE].driver_e = fs_m_in.REQ_DRIVER_E;
boottime = fs_m_in.REQ_BOOTTIME;
vfs_slink_storage = fs_m_in.REQ_SLINK_STORAGE;
sp = &super_block[0];
/* Fill in the super block. */
sp->s_dev = fs_dev; /* read_super() needs to know which dev */
r = read_super(sp);
/* Is it recognized as a Minix filesystem? */
if (r != OK) {
sp->s_dev = NO_DEV;
return(r);
}
/* Get the root inode of the mounted file system. */
root_ip = NIL_INODE; /* if 'r' not OK, make sure this is defined */
if (r == OK) {
if ( (root_ip = get_inode(fs_dev, ROOT_INODE)) == NIL_INODE)
r = err_code;
}
if (root_ip != NIL_INODE && root_ip->i_mode == 0) {
put_inode(root_ip);
r = EINVAL;
}
if (r != OK) return r;
sp->s_rd_only = fs_m_in.REQ_READONLY;
sp->s_is_root = fs_m_in.REQ_ISROOT;
/* Root inode properties */
fs_m_out.RES_INODE_NR = root_ip->i_num;
fs_m_out.RES_MODE = root_ip->i_mode;
fs_m_out.RES_FILE_SIZE = root_ip->i_size;
/* Partition properties */
fs_m_out.RES_MAXSIZE = sp->s_max_size;
fs_m_out.RES_BLOCKSIZE = sp->s_block_size;
return r;
}
/*===========================================================================*
* fs_mountpoint *
*===========================================================================*/
PUBLIC int fs_mountpoint()
{
/* This function looks up the mount point, it checks the condition whether
* the partition can be mounted on the inode or not. If ok, it gets the
* mountpoint inode's details and stores the mounted vmnt's index (in the
* vmnt table) so that it can be transferred back when the pathname lookup
* encounters a mountpoint.
*/
register struct inode *rip;
int r = OK;
mode_t bits;
/* Get inode */
caller_uid = fs_m_in.REQ_UID;
caller_gid = fs_m_in.REQ_GID;
/* Temporarily open the file. */
if ( (rip = get_inode(fs_dev, fs_m_in.REQ_INODE_NR)) == NIL_INODE) {
printf("MFS(%d) get_inode by fs_mountpoint() failed\n", SELF_E);
return(EINVAL);
}
/* It may not be busy. */
if (rip->i_count > 1) r = EBUSY;
/* It may not be special. */
bits = rip->i_mode & I_TYPE;
if (bits == I_BLOCK_SPECIAL || bits == I_CHAR_SPECIAL) r = ENOTDIR;
if ((rip->i_mode & I_TYPE) != I_DIRECTORY) r = ENOTDIR;
if (r != OK) {
put_inode(rip);
return r;
}
rip->i_mount = I_MOUNT;
rip->i_vmnt_ind = fs_m_in.REQ_VMNT_IND;
fs_m_out.m_source = rip->i_dev;/* Filled with the FS endp by the system */
fs_m_out.RES_INODE_NR = rip->i_num;
fs_m_out.RES_FILE_SIZE = rip->i_size;
fs_m_out.RES_MODE = rip->i_mode;
return r;
}
/*===========================================================================*
* fs_unmount *
*===========================================================================*/
PUBLIC int fs_unmount()
{
/* Unmount a file system by device number. */
struct super_block *sp, *sp1;
int count;
register struct inode *rip;
/* !!!!!!!!!!!!! REMOVE THIS LATER !!!!!!!!!!!!!!!!!!!!!!! */
/* Find the super block. */
sp = NIL_SUPER;
for (sp1 = &super_block[0]; sp1 < &super_block[NR_SUPERS]; sp1++) {
if (sp1->s_dev == fs_dev) {
sp = sp1;
break;
}
}
if (sp == NIL_SUPER) {
return(EINVAL);
}
/* !!!!!!!!!!!!! REMOVE THIS LATER !!!!!!!!!!!!!!!!!!!!!!! */
/* See if the mounted device is busy. Only 1 inode using it should be
* open -- the root inode -- and that inode only 1 time.
*/
count = 0;
for (rip = &inode[0]; rip < &inode[NR_INODES]; rip++) {
if (rip->i_count > 0 && rip->i_dev == fs_dev) {
/*printf("FSunmount DEV: %d inode: %d count: %d iaddr: %d\n",
rip->i_dev, rip->i_num, rip->i_count, rip);*/
count += rip->i_count;
}
}
if (count > 1) {
printf("MFS(%d) unmount: filesystem is busy %d\n", SELF_E, count);
return(EBUSY); /* can't umount a busy file system */
}
/* Put the root inode */
rip = get_inode(fs_dev, ROOT_INODE);
put_inode(rip);
put_inode(rip);
/* Sync the disk, and invalidate cache. */
(void) fs_sync(); /* force any cached blocks out of memory */
/*invalidate(fs_dev);*/ /* invalidate cache entries for this dev */
/* Finish off the unmount. */
sp->s_dev = NO_DEV;
return OK;
}