/*===========================================================================*
* mount_fs *
*===========================================================================*/
int mount_fs(
dev_t dev,
char mountpoint[PATH_MAX],
endpoint_t fs_e,
int rdonly,
char mount_label[LABEL_MAX] )
{
int i, r = OK, found, isroot, mount_root, con_reqs, slot;
struct fproc *tfp, *rfp;
struct dmap *dp;
struct vnode *root_node, *vp = NULL;
struct vmnt *new_vmp, *parent_vmp;
char *label;
struct node_details res;
struct lookup resolve;
/* Look up block device driver label when dev is not a pseudo-device */
label = "";
if (!is_nonedev(dev)) {
/* Get driver process' endpoint */
dp = &dmap[major(dev)];
if (dp->dmap_driver == NONE) {
printf("VFS: no driver for dev %d\n", dev);
return(EINVAL);
}
label = dp->dmap_label;
assert(strlen(label) > 0);
}
/* Scan vmnt table to see if dev already mounted. If not, find a free slot.*/
found = FALSE;
for (i = 0; i < NR_MNTS; ++i) {
if (vmnt[i].m_dev == dev) found = TRUE;
}
if (found) {
return(EBUSY);
} else if ((new_vmp = get_free_vmnt()) == NULL) {
return(ENOMEM);
}
if ((r = lock_vmnt(new_vmp, VMNT_EXCL)) != OK) return(r);
isroot = (strcmp(mountpoint, "/") == 0);
mount_root = (isroot && have_root < 2); /* Root can be mounted twice:
* 1: ramdisk
* 2: boot disk (e.g., harddisk)
*/
if (!mount_root) {
/* Get vnode of mountpoint */
lookup_init(&resolve, mountpoint, PATH_NOFLAGS, &parent_vmp, &vp);
resolve.l_vmnt_lock = VMNT_EXCL;
resolve.l_vnode_lock = VNODE_WRITE;
if ((vp = eat_path(&resolve, fp)) == NULL)
r = err_code;
else if (vp->v_ref_count == 1) {
/*Tell FS on which vnode it is mounted (glue into mount tree)*/
r = req_mountpoint(vp->v_fs_e, vp->v_inode_nr);
} else
r = EBUSY;
if (vp != NULL) {
/* Quickly unlock to allow back calls (from e.g. FUSE) to
* relock */
unlock_vmnt(parent_vmp);
}
if (r != OK) {
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
}
unlock_vmnt(new_vmp);
return(r);
}
}
/* We'll need a vnode for the root inode */
if ((root_node = get_free_vnode()) == NULL) {
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
}
unlock_vmnt(new_vmp);
return(err_code);
}
lock_vnode(root_node, VNODE_OPCL);
/* Record process as a system process */
if (isokendpt(fs_e, &slot) != OK) {
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
}
unlock_vnode(root_node);
unlock_vmnt(new_vmp);
return(EINVAL);
}
rfp = &fproc[slot];
rfp->fp_flags |= FP_SRV_PROC; /* File Servers are also services */
/* Store some essential vmnt data first */
new_vmp->m_fs_e = fs_e;
new_vmp->m_dev = dev;
if (rdonly) new_vmp->m_flags |= VMNT_READONLY;
else new_vmp->m_flags &= ~VMNT_READONLY;
/* Tell FS which device to mount */
new_vmp->m_flags |= VMNT_MOUNTING;
r = req_readsuper(fs_e, label, dev, rdonly, isroot, &res, &con_reqs);
new_vmp->m_flags &= ~VMNT_MOUNTING;
if (r != OK) {
mark_vmnt_free(new_vmp);
unlock_vnode(root_node);
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
}
unlock_vmnt(new_vmp);
return(r);
}
lock_bsf();
/* Fill in root node's fields */
root_node->v_fs_e = res.fs_e;
root_node->v_inode_nr = res.inode_nr;
root_node->v_mode = res.fmode;
root_node->v_uid = res.uid;
root_node->v_gid = res.gid;
root_node->v_size = res.fsize;
root_node->v_sdev = NO_DEV;
root_node->v_fs_count = 1;
root_node->v_ref_count = 1;
/* Root node is indeed on the partition */
root_node->v_vmnt = new_vmp;
root_node->v_dev = new_vmp->m_dev;
if (con_reqs == 0)
new_vmp->m_comm.c_max_reqs = 1; /* Default if FS doesn't tell us */
else
new_vmp->m_comm.c_max_reqs = con_reqs;
new_vmp->m_comm.c_cur_reqs = 0;
if (mount_root) {
/* Superblock and root node already read.
* Nothing else can go wrong. Perform the mount. */
new_vmp->m_root_node = root_node;
new_vmp->m_mounted_on = NULL;
strlcpy(new_vmp->m_label, mount_label, LABEL_MAX);
if (is_nonedev(dev)) alloc_nonedev(dev);
update_bspec(dev, fs_e, 0 /* Don't send new driver endpoint */);
ROOT_DEV = dev;
ROOT_FS_E = fs_e;
/* Replace all root and working directories */
for (i = 0, tfp = fproc; i < NR_PROCS; i++, tfp++) {
if (tfp->fp_pid == PID_FREE)
continue;
#define MAKEROOT(what) { \
if (what) put_vnode(what); \
dup_vnode(root_node); \
what = root_node; \
}
MAKEROOT(tfp->fp_rd);
MAKEROOT(tfp->fp_wd);
}
unlock_vnode(root_node);
unlock_vmnt(new_vmp);
have_root++; /* We have a (new) root */
unlock_bsf();
return(OK);
}
/* File types may not conflict. */
if (!S_ISDIR(vp->v_mode) && S_ISDIR(root_node->v_mode)) r = EISDIR;
/* If error, return the super block and both inodes; release the vmnt. */
if (r != OK) {
unlock_vnode(vp);
unlock_vnode(root_node);
mark_vmnt_free(new_vmp);
unlock_vmnt(new_vmp);
put_vnode(vp);
put_vnode(root_node);
unlock_bsf();
return(r);
}
/* Nothing else can go wrong. Perform the mount. */
new_vmp->m_mounted_on = vp;
new_vmp->m_root_node = root_node;
strlcpy(new_vmp->m_label, mount_label, LABEL_MAX);
/* Allocate the pseudo device that was found, if not using a real device. */
if (is_nonedev(dev)) alloc_nonedev(dev);
/* The new FS will handle block I/O requests for its device now. */
if (!(new_vmp->m_flags & VMNT_FORCEROOTBSF))
update_bspec(dev, fs_e, 0 /* Don't send new driver endpoint */);
unlock_vnode(vp);
unlock_vnode(root_node);
unlock_vmnt(new_vmp);
unlock_bsf();
return(OK);
}
dp = &dmap[(dev >> MAJOR) & BYTE];
if (dp->dmap_driver == NONE) {
printf("VFSmount: no driver for dev %x\n", dev);
return(EINVAL);
}
label= dp->dmap_label;
if (strlen(label) == 0)
{
panic(__FILE__, "vfs:mount_fs: no label for major", dev >> MAJOR);
}
#if 0
printf("vfs:mount_fs: label = '%s'\n", label);
#endif
/* Issue request */
r = req_readsuper(fs_e, label, dev, m_in.rd_only, isroot, &res);
if (r != OK) {
if (mounted_on)
put_vnode(mounted_on);
return r;
}
/* Fill in root node's fields */
root_node->v_fs_e = res.fs_e;
root_node->v_inode_nr = res.inode_nr;
root_node->v_mode = res.fmode;
root_node->v_uid = res.uid;
root_node->v_gid = res.gid;
root_node->v_size = res.fsize;
root_node->v_sdev = NO_DEV;
root_node->v_fs_count = 1;
