/*===========================================================================*
* do_link *
*===========================================================================*/
PUBLIC int do_link()
{
/* Perform the link(name1, name2) system call. */
int r;
endpoint_t linked_fs_e, link_lastdir_fs_e;
struct vnode *vp_o, *vp_d;
if (fetch_name(m_in.name1, m_in.name1_length, M1) != OK)
return(err_code);
/* Request lookup */
if ((r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &vp_o)) != OK) return r;
linked_fs_e = vp_o->v_fs_e;
/* Does the final directory of 'name2' exist? */
if (fetch_name(m_in.name2, m_in.name2_length, M1) != OK) {
put_vnode(vp_o);
return(err_code);
}
/* Request lookup */
if ((r = lookup_lastdir(0 /*!use_realuid*/, &vp_d)) != OK)
{
put_vnode(vp_o);
return r;
}
link_lastdir_fs_e = vp_d->v_fs_e;
/* Check for links across devices. */
if (linked_fs_e != link_lastdir_fs_e)
{
put_vnode(vp_o);
put_vnode(vp_d);
return EXDEV;
}
/* Make sure that the object is a directory */
if ((vp_d->v_mode & I_TYPE) != I_DIRECTORY)
{
put_vnode(vp_o);
put_vnode(vp_d);
return ENOTDIR;
}
r= forbidden(vp_d, W_BIT|X_BIT, 0 /*!use_realuid*/);
if (r != OK)
{
put_vnode(vp_o);
put_vnode(vp_d);
return r;
}
/* Issue request */
r= req_link(linked_fs_e, vp_d->v_inode_nr, user_fullpath, vp_o->v_inode_nr);
put_vnode(vp_o);
put_vnode(vp_d);
return r;
}
/*===========================================================================*
* do_utime *
*===========================================================================*/
PUBLIC int do_utime()
{
/* Perform the utime(name, timep) system call. */
register int len;
int r;
uid_t uid;
time_t actime, modtime;
struct vnode *vp;
/* Adjust for case of 'timep' being NULL;
* utime_strlen then holds the actual size: strlen(name)+1.
*/
len = m_in.utime_length;
if (len == 0) len = m_in.utime_strlen;
if (fetch_name(m_in.utime_file, len, M1) != OK) return(err_code);
/* Request lookup */
if ((r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &vp)) != OK) return r;
/* Fill in request fields.*/
if (m_in.utime_length == 0) {
actime = modtime = clock_time();
} else {
actime = m_in.utime_actime;
modtime = m_in.utime_modtime;
}
uid= fp->fp_effuid;
r= OK;
if (vp->v_uid != uid && uid != SU_UID) r = EPERM;
if (m_in.utime_length == 0 && r != OK)
{
/* With a null times pointer, updating the times (to the current time)
* is allow if the object is writable.
*/
r = forbidden(vp, W_BIT, 0 /*!use_realuid*/);
}
if (r != OK)
{
put_vnode(vp);
return r;
}
/* Issue request */
r= req_utime(vp->v_fs_e, vp->v_inode_nr, actime, modtime);
put_vnode(vp);
return r;
}
/*===========================================================================*
* do_truncate *
*===========================================================================*/
PUBLIC int do_truncate()
{
/* truncate_inode() does the actual work of do_truncate() and do_ftruncate().
* do_truncate() and do_ftruncate() have to get hold of the inode, either
* by name or fd, do checks on it, and call truncate_inode() to do the
* work.
*/
struct vnode *vp;
int r;
printf("in do_truncate\n");
if (fetch_name(m_in.m2_p1, m_in.m2_i1, M1) != OK) return err_code;
/* Request lookup */
if ((r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &vp)) != OK) return r;
if ((r = forbidden(vp, W_BIT, 0 /*!use_realuid*/)) == OK)
r = truncate_vn(vp, m_in.m2_l1);
put_vnode(vp);
return r;
}
/*===========================================================================*
* mount *
*===========================================================================*/
PRIVATE int mount_fs(endpoint_t fs_e)
{
/* Perform the mount(name, mfile, rd_only) system call. */
int rdir, mdir; /* TRUE iff {root|mount} file is dir */
int i, r, found, isroot, replace_root;
struct fproc *tfp;
struct dmap *dp;
dev_t dev;
message m;
struct vnode *root_node, *mounted_on = NULL, *bspec;
struct vmnt *vmp;
char *label;
struct node_details res;
SANITYCHECK;
/* Only the super-user may do MOUNT. */
if (!super_user) return(EPERM);
/* If FS not yet logged in, save message and suspend mount */
if (last_login_fs_e != fs_e) {
mount_m_in = m_in;
return SUSPEND;
}
/* Mount request got after FS login or
* FS login arrived after a suspended mount */
last_login_fs_e = NONE;
/* Clear endpoint field */
mount_m_in.m1_p3 = (char *) NONE;
/* If 'name' is not for a block special file, return error. */
if (fetch_name(m_in.name1, m_in.name1_length, M1) != OK) return(err_code);
/* Convert name to device number */
if ((dev = name_to_dev()) == NO_DEV) return(err_code);
/* Check whether there is a block special file open which uses the
* same device (partition) */
for (bspec = &vnode[0]; bspec < &vnode[NR_VNODES]; ++bspec) {
if (bspec->v_ref_count > 0 && bspec->v_sdev == dev) {
/* Found, sync the buffer cache */
req_sync(bspec->v_fs_e);
break;
/* Note: there are probably some blocks in the FS process' buffer
* cache which contain data on this minor, although they will be
* purged since the handling moves to the new FS process (if
* everything goes well with the mount...)
*/
}
}
/* Didn't find? */
if (bspec == &vnode[NR_VNODES] && bspec->v_sdev != dev)
bspec = NULL;
/* Scan vmnt table to see if dev already mounted, if not,
* find a free slot.*/
found = FALSE;
vmp = NIL_VMNT;
for (i = 0; i < NR_MNTS; ++i) {
if (vmnt[i].m_dev == dev) {
vmp = &vmnt[i];
found = TRUE;
break;
}
else if (!vmp && vmnt[i].m_dev == NO_DEV) {
vmp = &vmnt[i];
}
}
/* Partition was/is already mounted */
if (found) {
/* It is possible that we have an old root lying around that
* needs to be remounted. */
if (vmp->m_mounted_on || vmp->m_mounted_on == fproc[FS_PROC_NR].fp_rd) {
/* Normally, m_mounted_on refers to the mount point. For a
* root filesystem, m_mounted_on is equal to the root vnode.
* We assume that the root of FS is always the real root. If
* the two vnodes are different or if the root of FS is equal
* to the root of the filesystem we found, we found a
* filesystem that is in use.
*/
return EBUSY; /* already mounted */
}
if(vmp->m_mounted_on)
panic("vfs", "root unexpectedly mounted somewhere", NO_NUM);
if (root_dev == vmp->m_dev)
panic("fs", "inconsistency remounting old root", NO_NUM);
/* Now get the inode of the file to be mounted on. */
if (fetch_name(m_in.name2, m_in.name2_length, M1) != OK) {
return(err_code);
}
/* Request lookup */
r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &mounted_on);
if (r != OK) return r;
if (mounted_on->v_ref_count != 1)
{
put_vnode(mounted_on);
printf("vfs:mount_fs: mount point is busy\n");
return EBUSY;
}
/* Issue mountpoint request */
r = req_mountpoint(mounted_on->v_fs_e, mounted_on->v_inode_nr);
if (r != OK)
{
put_vnode(mounted_on);
printf("vfs:mount_fs: req_mountpoint_s failed with %d\n", r);
return r;
}
/* Get the root inode of the mounted file system. */
root_node = vmp->m_root_node;
/* File types may not conflict. */
if (r == OK) {
mdir = ((mounted_on->v_mode & I_TYPE) == I_DIRECTORY);
/* TRUE iff dir */
rdir = ((root_node->v_mode & I_TYPE) == I_DIRECTORY);
if (!mdir && rdir) r = EISDIR;
}
/* If error, return the mount point. */
if (r != OK) {
put_vnode(mounted_on);
return(r);
}
/* Nothing else can go wrong. Perform the mount. */
vmp->m_mounted_on = mounted_on;
vmp->m_flags = m_in.rd_only;
allow_newroot = 0; /* The root is now fixed */
return(OK);
}
/* Fetch the name of the mountpoint */
if (fetch_name(m_in.name2, m_in.name2_length, M1) != OK) {
return(err_code);
}
isroot= (strcmp(user_fullpath, "/") == 0);
replace_root= (isroot && allow_newroot);
if (!replace_root)
{
/* Get mount point and inform the FS it is on. */
#if 0
printf("vfs:mount_fs: mount point at '%s'\n", user_fullpath);
#endif
r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &mounted_on);
if (r != OK)
return r;
/* Issue mountpoint request */
r = req_mountpoint(mounted_on->v_fs_e, mounted_on->v_inode_nr);
if (r != OK) {
put_vnode(mounted_on);
printf("vfs:mount_fs: req_mountpoint_s failed with %d\n", r);
return r;
}
}
/* We'll need a vnode for the root inode, check whether there is one */
if ((root_node = get_free_vnode(__FILE__, __LINE__)) == NIL_VNODE) {
printf("VFSmount: no free vnode available\n");
return ENFILE;
}
/* Get driver process' endpoint */
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);
}