/* assumes ctl_mtx is held */
static void _unload_ssd(struct ssd_info * ssd)
{
if (NULL == ssd)
return;
/* first remove it from the set of cache devices, no more
* requests will be queued to this device beyond this point */
if (ssd->cdev) {
sce_rmcdev(ssd->cdev);
ssd->cdev = NULL;
}
/* make offline and quiesce requests already in flight */
if (ssd->online) {
ssd->online = 0;
list_del_rcu(&ssd->list);
wmb();
synchronize_rcu(); /* wait for references to quiesce */
while(atomic_read(&ssd->nr_ref))
schedule();
gctx.nr_ssd--;
}
if (ssd->bdev) {
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,38)
blkdev_put(ssd->bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
close_bdev_exclusive(ssd->bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
#else
ERR("Kernel version < 2.6.28 currently not supported.\n");
#endif
ssd->bdev = NULL;
}
}
static int
nilfs_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data, struct vfsmount *mnt)
{
struct nilfs_super_data sd;
struct super_block *s;
fmode_t mode = FMODE_READ;
struct the_nilfs *nilfs;
int err, need_to_close = 1;
if (!(flags & MS_RDONLY))
mode |= FMODE_WRITE;
sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
if (IS_ERR(sd.bdev))
return PTR_ERR(sd.bdev);
/*
* To get mount instance using sget() vfs-routine, NILFS needs
* much more information than normal filesystems to identify mount
* instance. For snapshot mounts, not only a mount type (ro-mount
* or rw-mount) but also a checkpoint number is required.
*/
sd.cno = 0;
sd.flags = flags;
if (nilfs_identify((char *)data, &sd)) {
err = -EINVAL;
goto failed;
}
nilfs = find_or_create_nilfs(sd.bdev);
if (!nilfs) {
err = -ENOMEM;
goto failed;
}
mutex_lock(&nilfs->ns_mount_mutex);
if (!sd.cno) {
/*
* Check if an exclusive mount exists or not.
* Snapshot mounts coexist with a current mount
* (i.e. rw-mount or ro-mount), whereas rw-mount and
* ro-mount are mutually exclusive.
*/
down_read(&nilfs->ns_super_sem);
if (nilfs->ns_current &&
((nilfs->ns_current->s_super->s_flags ^ flags)
& MS_RDONLY)) {
up_read(&nilfs->ns_super_sem);
err = -EBUSY;
goto failed_unlock;
}
up_read(&nilfs->ns_super_sem);
}
/*
* Find existing nilfs_sb_info struct
*/
sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
/*
* Get super block instance holding the nilfs_sb_info struct.
* A new instance is allocated if no existing mount is present or
* existing instance has been unmounted.
*/
s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
if (sd.sbi)
nilfs_put_sbinfo(sd.sbi);
if (IS_ERR(s)) {
err = PTR_ERR(s);
goto failed_unlock;
}
if (!s->s_root) {
char b[BDEVNAME_SIZE];
/* New superblock instance created */
s->s_flags = flags;
s->s_mode = mode;
strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
sb_set_blocksize(s, block_size(sd.bdev));
err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
nilfs);
if (err)
goto cancel_new;
s->s_flags |= MS_ACTIVE;
need_to_close = 0;
}
mutex_unlock(&nilfs->ns_mount_mutex);
put_nilfs(nilfs);
if (need_to_close)
close_bdev_exclusive(sd.bdev, mode);
simple_set_mnt(mnt, s);
return 0;
failed_unlock:
mutex_unlock(&nilfs->ns_mount_mutex);
put_nilfs(nilfs);
failed:
close_bdev_exclusive(sd.bdev, mode);
return err;
cancel_new:
/* Abandoning the newly allocated superblock */
mutex_unlock(&nilfs->ns_mount_mutex);
put_nilfs(nilfs);
deactivate_locked_super(s);
/*
* deactivate_locked_super() invokes close_bdev_exclusive().
* We must finish all post-cleaning before this call;
* put_nilfs() needs the block device.
*/
return err;
}
/******************************************************************************
*
* axfs_get_sb_block
*
* Description:
* Populates a axfs_fill_super_info struct after sanity checking the
* block device
*
* Parameters:
* (IN) fs_type - pointer to file_system_type
*
* (IN) flags - mount flags
*
* (IN) dev_name - block device name passed in from mount
*
* (IN) secondary_blk_dev - block device name enter from mount -o
*
* Returns:
* pointer to a axfs_file_super_info or an error pointer
*
*****************************************************************************/
static struct axfs_fill_super_info *axfs_get_sb_block(struct file_system_type *fs_type,
int flags, const char *dev_name, char *secondary_blk_dev)
{
struct nameidata nd;
struct buffer_head *bh = NULL;
struct axfs_fill_super_info *output;
struct block_device *bdev = NULL;
int err;
err = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
if (err)
return ERR_PTR(-EINVAL);
if (secondary_blk_dev) {
printk(KERN_ERR "axfs: can't mount 2 block device's \"%s\" and \"%s\"\n", dev_name, secondary_blk_dev);
err = -EINVAL;
goto path_out;
}
if (!S_ISBLK(nd.path.dentry->d_inode->i_mode)) {
err = -EINVAL;
goto path_out;
}
if (nd.path.mnt->mnt_flags & MNT_NODEV) {
err = -EACCES;
goto path_out;
}
bdev = open_bdev_exclusive(dev_name, flags, fs_type);
if (IS_ERR(bdev)){
err = PTR_ERR(bdev);
goto path_out;
}
bh = __bread(bdev, 0, bdev->bd_block_size);
if (!bh) {
err = -EIO;
goto out;
}
output = (struct axfs_fill_super_info *)vmalloc(sizeof(struct axfs_fill_super_info));
if(!output) {
err = -ENOMEM;
goto out;
}
output->onmedia_super_block = (struct axfs_super_onmedia *)vmalloc(sizeof(struct axfs_super_onmedia));
if(!output->onmedia_super_block) {
err = -ENOMEM;
goto out;
}
memcpy((char *)output->onmedia_super_block, bh->b_data, sizeof(struct axfs_super_onmedia));
if(IS_ERR(output)) {
err = PTR_ERR(output);
goto out;
}
output->physical_start_address = 0;
output->virtual_start_address = 0;
path_put(&nd.path);
close_bdev_exclusive(bdev, flags);
free_buffer_head(bh);
return output;
out:
close_bdev_exclusive(bdev,flags);
if (bh) {
free_buffer_head(bh);
}
path_out:
path_put(&nd.path);
printk(KERN_NOTICE "axfs_get_sb_block(): Invalid device \"%s\"\n",
dev_name);
return ERR_PTR(err);
}
static int
nilfs_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data, struct vfsmount *mnt)
{
struct nilfs_super_data sd;
struct super_block *s;
fmode_t mode = FMODE_READ;
struct dentry *root_dentry;
int err, s_new = false;
if (!(flags & MS_RDONLY))
mode |= FMODE_WRITE;
sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
if (IS_ERR(sd.bdev))
return PTR_ERR(sd.bdev);
sd.cno = 0;
sd.flags = flags;
if (nilfs_identify((char *)data, &sd)) {
err = -EINVAL;
goto failed;
}
/*
* once the super is inserted into the list by sget, s_umount
* will protect the lockfs code from trying to start a snapshot
* while we are mounting
*/
mutex_lock(&sd.bdev->bd_fsfreeze_mutex);
if (sd.bdev->bd_fsfreeze_count > 0) {
mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
err = -EBUSY;
goto failed;
}
s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, sd.bdev);
mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
if (IS_ERR(s)) {
err = PTR_ERR(s);
goto failed;
}
if (!s->s_root) {
char b[BDEVNAME_SIZE];
s_new = true;
/* New superblock instance created */
s->s_flags = flags;
s->s_mode = mode;
strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
sb_set_blocksize(s, block_size(sd.bdev));
err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
if (err)
goto failed_super;
s->s_flags |= MS_ACTIVE;
} else if (!sd.cno) {
int busy = false;
if (nilfs_tree_was_touched(s->s_root)) {
busy = nilfs_try_to_shrink_tree(s->s_root);
if (busy && (flags ^ s->s_flags) & MS_RDONLY) {
printk(KERN_ERR "NILFS: the device already "
"has a %s mount.\n",
(s->s_flags & MS_RDONLY) ?
"read-only" : "read/write");
err = -EBUSY;
goto failed_super;
}
}
if (!busy) {
/*
* Try remount to setup mount states if the current
* tree is not mounted and only snapshots use this sb.
*/
err = nilfs_remount(s, &flags, data);
if (err)
goto failed_super;
}
}
if (sd.cno) {
err = nilfs_attach_snapshot(s, sd.cno, &root_dentry);
if (err)
goto failed_super;
} else {
root_dentry = dget(s->s_root);
}
if (!s_new)
close_bdev_exclusive(sd.bdev, mode);
mnt->mnt_sb = s;
mnt->mnt_root = root_dentry;
return 0;
failed_super:
deactivate_locked_super(s);
failed:
if (!s_new)
close_bdev_exclusive(sd.bdev, mode);
return err;
}