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/* Created (MFS based):
* February 2010 (Evgeniy Ivanov)
*/
#include "fs.h"
#include "buf.h"
#include "inode.h"
#include "super.h"
#include <stdlib.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;
u32_t mask;
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. */
if(!(superblock = malloc(sizeof(*superblock))))
panic("Can't allocate memory for superblock.");
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);
}
if (superblock->s_rev_level != EXT2_GOOD_OLD_REV) {
struct super_block *sp = superblock; /* just shorter name */
mask = ~SUPPORTED_INCOMPAT_FEATURES;
if (HAS_INCOMPAT_FEATURE(sp, mask)) {
if (HAS_INCOMPAT_FEATURE(sp, INCOMPAT_COMPRESSION & mask))
printf("ext2: fs compression is not supported by server\n");
if (HAS_INCOMPAT_FEATURE(sp, INCOMPAT_FILETYPE & mask))
printf("ext2: fs in dir filetype is not supported by server\n");
if (HAS_INCOMPAT_FEATURE(sp, INCOMPAT_RECOVER & mask))
printf("ext2: fs recovery is not supported by server\n");
if (HAS_INCOMPAT_FEATURE(sp, INCOMPAT_JOURNAL_DEV & mask))
printf("ext2: fs journal dev is not supported by server\n");
if (HAS_INCOMPAT_FEATURE(sp, INCOMPAT_META_BG & mask))
printf("ext2: fs meta bg is not supported by server\n");
return(EINVAL);
}
mask = ~SUPPORTED_RO_COMPAT_FEATURES;
if (HAS_RO_COMPAT_FEATURE(sp, mask)) {
if (HAS_RO_COMPAT_FEATURE(sp, RO_COMPAT_SPARSE_SUPER & mask)) {
printf("ext2: sparse super is not supported by server, \
remount read-only\n");
}
if (HAS_RO_COMPAT_FEATURE(sp, RO_COMPAT_LARGE_FILE & mask)) {
printf("ext2: large files are not supported by server, \
remount read-only\n");
}
if (HAS_RO_COMPAT_FEATURE(sp, RO_COMPAT_BTREE_DIR & mask)) {
printf("ext2: dir's btree is not supported by server, \
remount read-only\n");
}
return(EINVAL);
}
}
if (superblock->s_state == EXT2_ERROR_FS) {
printf("ext2: filesystem wasn't cleanly unmounted last time\n");
superblock->s_dev = NO_DEV;
bdev_close(fs_dev);
return(EINVAL);
}
lmfs_set_blocksize(superblock->s_block_size);
lmfs_set_blockusage(superblock->s_blocks_count,
superblock->s_blocks_count - superblock->s_free_blocks_count);
/* Get the root inode of the mounted file system. */
if ( (root_ip = get_inode(fs_dev, ROOT_INODE)) == NULL) {
printf("ext2: couldn't get root inode\n");
superblock->s_dev = NO_DEV;
bdev_close(fs_dev);
return(EINVAL);
}
if (root_ip != NULL && 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);
}
if (root_ip != NULL && (root_ip->i_mode & I_TYPE) != I_DIRECTORY) {
printf("%s:%d root inode has wrong type, it's not a DIR\n",
__FILE__, __LINE__);
put_inode(root_ip);
superblock->s_dev = NO_DEV;
bdev_close(fs_dev);
return(EINVAL);
}
superblock->s_rd_only = readonly;
if (!readonly) {
superblock->s_state = EXT2_ERROR_FS;
superblock->s_mnt_count++;
superblock->s_mtime = clock_time(NULL);
write_super(superblock); /* Commit info, we just set above */
}
/* 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;
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 by device number. */
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("ext2: file system has %d in-use inodes!\n", count);
if ((root_ip = find_inode(fs_dev, ROOT_INODE)) == NULL)
panic("ext2: couldn't find root inode");
/* Sync fs data before checking count. In some cases VFS can force unmounting
* and it will damage unsynced FS. We don't sync before checking root_ip since
* if it is missing then something strange happened with FS, so it's better
* to not use possibly corrupted data for syncing.
*/
if (!superblock->s_rd_only) {
/* force any cached blocks out of memory */
fs_sync();
}
put_inode(root_ip);
if (!superblock->s_rd_only) {
superblock->s_wtime = clock_time(NULL);
superblock->s_state = EXT2_VALID_FS;
write_super(superblock); /* Commit info, we just set above */
}
/* Close the device the file system lives on. */
bdev_close(fs_dev);
/* Throw all 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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