minix/servers/mfs/mount.c
Thomas Veerman 6bbcab3ec4 Clean up MFS a bit:
- Remove unused includes.
 - Add include guards to headers.
 - Use unsigned variables in case they're never going to hold a negative
   value. This causes GCC's complaints to disappear and should make flexelint
   a lot happier, too.
 - Make functions private when they're used only within a module.
 - Remove unused variables.
 - Add casts where appropriate.
2010-06-01 12:35:33 +00:00

171 lines
4.8 KiB
C

#include "fs.h"
#include "inode.h"
#include "super.h"
#include "drivers.h"
#include <minix/ds.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 inode *root_ip;
cp_grant_id_t label_gid;
size_t label_len;
int r;
endpoint_t driver_e;
int readonly, isroot;
fs_dev = (dev_t) fs_m_in.REQ_DEV;
label_gid = (cp_grant_id_t) fs_m_in.REQ_GRANT;
label_len = (size_t) fs_m_in.REQ_PATH_LEN;
readonly = (fs_m_in.REQ_FLAGS & REQ_RDONLY) ? 1 : 0;
isroot = (fs_m_in.REQ_FLAGS & REQ_ISROOT) ? 1 : 0;
if (label_len > sizeof(fs_dev_label))
return(EINVAL);
r = sys_safecopyfrom(fs_m_in.m_source, label_gid, (vir_bytes) 0,
(vir_bytes) fs_dev_label, label_len, D);
if (r != OK) {
printf("MFS %s:%d safecopyfrom failed: %d\n", __FILE__, __LINE__, r);
return(EINVAL);
}
r = ds_retrieve_label_endpt(fs_dev_label, &driver_e);
if (r != OK) {
printf("MFS %s:%d ds_retrieve_label_endpt failed for '%s': %d\n",
__FILE__, __LINE__, fs_dev_label, r);
return(EINVAL);
}
/* Map the driver endpoint for this major */
driver_endpoints[major(fs_dev)].driver_e = driver_e;
/* Open the device the file system lives on. */
if (dev_open(driver_e, fs_dev, driver_e,
readonly ? R_BIT : (R_BIT|W_BIT) ) != OK) {
return(EINVAL);
}
/* Fill in the super block. */
superblock.s_dev = fs_dev; /* read_super() needs to know which dev */
r = read_super(&superblock);
/* Is it recognized as a Minix filesystem? */
if (r != OK) {
superblock.s_dev = NO_DEV;
dev_close(driver_e, fs_dev);
return(r);
}
set_blocksize(superblock.s_block_size);
/* Get the root inode of the mounted file system. */
if( (root_ip = get_inode(fs_dev, ROOT_INODE)) == NULL) {
printf("MFS: couldn't get root inode\n");
superblock.s_dev = NO_DEV;
dev_close(driver_e, fs_dev);
return(EINVAL);
}
if(root_ip->i_mode == 0) {
printf("%s:%d zero mode for root inode?\n", __FILE__, __LINE__);
put_inode(root_ip);
superblock.s_dev = NO_DEV;
dev_close(driver_e, fs_dev);
return(EINVAL);
}
superblock.s_rd_only = readonly;
superblock.s_is_root = 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_LO = root_ip->i_size;
fs_m_out.RES_UID = root_ip->i_uid;
fs_m_out.RES_GID = root_ip->i_gid;
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.
*/
register struct inode *rip;
int r = OK;
mode_t bits;
/* Temporarily open the file. */
if( (rip = get_inode(fs_dev, (ino_t) fs_m_in.REQ_INODE_NR)) == NULL)
return(EINVAL);
if(rip->i_mountpoint) r = EBUSY;
/* It may not be special. */
bits = rip->i_mode & I_TYPE;
if (bits == I_BLOCK_SPECIAL || bits == I_CHAR_SPECIAL) r = ENOTDIR;
put_inode(rip);
if(r == OK) rip->i_mountpoint = TRUE;
return(r);
}
/*===========================================================================*
* fs_unmount *
*===========================================================================*/
PUBLIC int fs_unmount()
{
/* Unmount a file system by device number. */
int count;
struct inode *rip, *root_ip;
if(superblock.s_dev != fs_dev) return(EINVAL);
/* 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) count += rip->i_count;
if ((root_ip = find_inode(fs_dev, ROOT_INODE)) == NULL) {
panic("MFS: couldn't find root inode\n");
return(EINVAL);
}
if (count > 1) return(EBUSY); /* can't umount a busy file system */
put_inode(root_ip);
/* force any cached blocks out of memory */
(void) fs_sync();
/* Close the device the file system lives on. */
dev_close(driver_endpoints[major(fs_dev)].driver_e, fs_dev);
/* Finish off the unmount. */
superblock.s_dev = NO_DEV;
unmountdone = TRUE;
return(OK);
}