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#include "fs.h"
#include "inode.h"
#include "super.h"
#include <minix/vfsif.h>
#include <minix/bdev.h>
/*===========================================================================*
* fs_mount *
*===========================================================================*/
int fs_mount(dev_t dev, unsigned int flags, struct fsdriver_node *root_node,
unsigned int *res_flags)
{
/* This function reads the superblock of the partition, gets the root inode
* and sends back the details of them.
*/
struct inode *root_ip;
int r, readonly;
fs_dev = dev;
readonly = (flags & REQ_RDONLY) ? 1 : 0;
/* Open the device the file system lives on. */
if (bdev_open(fs_dev, readonly ? BDEV_R_BIT : (BDEV_R_BIT|BDEV_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;
bdev_close(fs_dev);
return(r);
}
/* clean check: if rw and not clean, switch to readonly */
if(!(superblock.s_flags & MFSFLAG_CLEAN) && !readonly) {
if(bdev_close(fs_dev) != OK)
panic("couldn't bdev_close after found unclean FS");
readonly = 1;
if (bdev_open(fs_dev, BDEV_R_BIT) != OK) {
panic("couldn't bdev_open after found unclean FS");
return(EINVAL);
}
printf("MFS: WARNING: FS 0x%llx unclean, mounting readonly\n", fs_dev);
}
lmfs_set_blocksize(superblock.s_block_size);
/* Compute the current number of used zones, and report it to libminixfs.
* Note that libminixfs really wants numbers of *blocks*, but this MFS
* implementation dropped support for differing zone/block sizes a while ago.
*/
used_zones = superblock.s_zones - count_free_bits(&superblock, ZMAP);
lmfs_set_blockusage(superblock.s_zones, used_zones);
/* 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;
bdev_close(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;
bdev_close(fs_dev);
return(EINVAL);
}
superblock.s_rd_only = readonly;
/* Root inode properties */
root_node->fn_ino_nr = root_ip->i_num;
root_node->fn_mode = root_ip->i_mode;
root_node->fn_size = root_ip->i_size;
root_node->fn_uid = root_ip->i_uid;
root_node->fn_gid = root_ip->i_gid;
root_node->fn_dev = NO_DEV;
*res_flags = RES_NOFLAGS;
/* Mark it dirty */
if(!superblock.s_rd_only) {
superblock.s_flags &= ~MFSFLAG_CLEAN;
if(write_super(&superblock) != OK)
panic("mounting: couldn't write dirty superblock");
}
return(r);
}
/*===========================================================================*
* fs_mountpt *
*===========================================================================*/
int fs_mountpt(ino_t ino_nr)
{
/* 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_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 *
*===========================================================================*/
void fs_unmount(void)
{
/* Unmount a file system. */
int count;
struct inode *rip, *root_ip;
/* See if the mounted device is busy. Only 1 inode using it should be
* open --the root inode-- and that inode only 1 time. This is an integrity
* check only: VFS expects the unmount to succeed either way.
*/
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 (count != 1)
printf("MFS: file system has %d in-use inodes!\n", count);
if ((root_ip = find_inode(fs_dev, ROOT_INODE)) == NULL)
panic("MFS: couldn't find root inode\n");
put_inode(root_ip);
/* force any cached blocks out of memory */
fs_sync();
/* Mark it clean if we're allowed to write _and_ it was clean originally. */
if (!superblock.s_rd_only) {
superblock.s_flags |= MFSFLAG_CLEAN;
write_super(&superblock);
}
/* Close the device the file system lives on. */
bdev_close(fs_dev);
/* Throw out blocks out of the VM cache, to prevent corruption later. */
lmfs_invalidate(fs_dev);
/* Finish off the unmount. */
superblock.s_dev = NO_DEV;
}
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