/*===========================================================================*
* new_node *
*===========================================================================*/
static struct vnode *new_node(mode_t bits)
{
struct vnode *dirp, *vp;
int r;
struct node_details res;
struct vnode *rest;
/* See if the path can be opened down to the last directory. */
if ((dirp = last_dir()) == NIL_VNODE) return(NIL_VNODE);
/* The final directory is accessible. Get final component of the path. */
vp = advance(dirp, 0);
if (vp == NIL_VNODE && err_code == -ENOENT) {
/* Last path component does not exist. Make a new directory entry. */
if ((vp = get_free_vnode()) == NIL_VNODE) {
/* Can't create new vnode: out of vnodes. */
put_vnode(dirp);
return(NIL_VNODE);
}
if ((r = forbidden(dirp, W_BIT|X_BIT)) != 0 ||
(r = req_create(dirp->v_fs_e, dirp->v_inode_nr,bits, fp->fp_effuid,
fp->fp_effgid, user_fullpath, &res)) != 0 ) {
/* Can't create new directory entry: either no permission or
something else is wrong. */
put_vnode(dirp);
err_code = r;
return(NIL_VNODE);
}
/* Store results and mark vnode in use */
vp->v_fs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_size = res.fsize;
vp->v_uid = res.uid;
vp->v_gid = res.gid;
vp->v_sdev = res.dev;
vp->v_vmnt = dirp->v_vmnt;
vp->v_dev = vp->v_vmnt->m_dev;
vp->v_fs_count = 1;
vp->v_ref_count = 1;
} else {
/* Either last component exists, or there is some other problem. */
if (vp != NIL_VNODE)
r = -EEXIST;
else
r = err_code;
}
err_code = r;
put_vnode(dirp);
return(vp);
}
vnode_t *get_vnode(uint32_t driver_num, uint32_t inode_num)
{
vnode_t *vnode = find_vnode(driver_num, inode_num);
if(!vnode)
{
vnode = get_free_vnode();
vfs_msg_getnode *getnode_msg = (vfs_msg_getnode *)calloc(sizeof(vfs_msg_getnode));
getnode_msg->msg_type = VFSM_GETNODE;
getnode_msg->node.driver_num = driver_num;
getnode_msg->node.inode_num = inode_num;
send2(driver_num, getnode_msg);
free(getnode_msg);
getnode_msg = waitmsg(driver_num,0);
if(getnode_msg->node.driver_num)
{
memcopy((uint8_t *)vnode, (uint8_t *)&getnode_msg->node, sizeof(vnode_t));
} else {
_syscall_printf("\nGetnode failed!",0);
}
free(getnode_msg);
}
return vnode;
}
/*===========================================================================*
* new_node *
*===========================================================================*/
static struct vnode *new_node(struct lookup *resolve, int oflags, mode_t bits)
{
/* Try to create a new inode and return a pointer to it. If the inode already
exists, return a pointer to it as well, but set err_code accordingly.
NULL is returned if the path cannot be resolved up to the last
directory, or when the inode cannot be created due to permissions or
otherwise. */
struct vnode *dirp, *vp;
struct vmnt *dir_vmp, *vp_vmp;
int r;
struct node_details res;
struct lookup findnode;
char *path;
path = resolve->l_path; /* For easy access */
lookup_init(&findnode, path, resolve->l_flags, &dir_vmp, &dirp);
findnode.l_vmnt_lock = VMNT_WRITE;
findnode.l_vnode_lock = VNODE_WRITE; /* dir node */
/* When O_CREAT and O_EXCL flags are set, the path may not be named by a
* symbolic link. */
if (oflags & O_EXCL) findnode.l_flags |= PATH_RET_SYMLINK;
/* See if the path can be opened down to the last directory. */
if ((dirp = last_dir(&findnode, fp)) == NULL) return(NULL);
/* The final directory is accessible. Get final component of the path. */
lookup_init(&findnode, findnode.l_path, findnode.l_flags, &vp_vmp, &vp);
findnode.l_vmnt_lock = VMNT_WRITE;
findnode.l_vnode_lock = (oflags & O_TRUNC) ? VNODE_WRITE : VNODE_OPCL;
vp = advance(dirp, &findnode, fp);
assert(vp_vmp == NULL); /* Lookup to last dir should have yielded lock
* on vmp or final component does not exist.
* Either way, vp_vmp ought to be not set.
*/
/* The combination of a symlink with absolute path followed by a danglink
* symlink results in a new path that needs to be re-resolved entirely. */
if (path[0] == '/') {
unlock_vnode(dirp);
unlock_vmnt(dir_vmp);
put_vnode(dirp);
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
}
return new_node(resolve, oflags, bits);
}
if (vp == NULL && err_code == ENOENT) {
/* Last path component does not exist. Make a new directory entry. */
if ((vp = get_free_vnode()) == NULL) {
/* Can't create new entry: out of vnodes. */
unlock_vnode(dirp);
unlock_vmnt(dir_vmp);
put_vnode(dirp);
return(NULL);
}
lock_vnode(vp, VNODE_OPCL);
if ((r = forbidden(fp, dirp, W_BIT|X_BIT)) != OK ||
(r = req_create(dirp->v_fs_e, dirp->v_inode_nr,bits, fp->fp_effuid,
fp->fp_effgid, path, &res)) != OK ) {
/* Can't create inode either due to permissions or some other
* problem. In case r is EEXIST, we might be dealing with a
* dangling symlink.*/
if (r == EEXIST) {
struct vnode *slp, *old_wd;
/* Resolve path up to symlink */
findnode.l_flags = PATH_RET_SYMLINK;
findnode.l_vnode_lock = VNODE_READ;
findnode.l_vnode = &slp;
slp = advance(dirp, &findnode, fp);
if (slp != NULL) {
if (S_ISLNK(slp->v_mode)) {
/* Get contents of link */
r = req_rdlink(slp->v_fs_e,
slp->v_inode_nr,
VFS_PROC_NR,
(vir_bytes) path,
PATH_MAX - 1, 0);
if (r < 0) {
/* Failed to read link */
unlock_vnode(slp);
unlock_vnode(dirp);
unlock_vmnt(dir_vmp);
put_vnode(slp);
put_vnode(dirp);
err_code = r;
return(NULL);
}
path[r] = '\0'; /* Terminate path */
}
unlock_vnode(slp);
put_vnode(slp);
}
/* Try to create the inode the dangling symlink was
* pointing to. We have to use dirp as starting point
* as there might be multiple successive symlinks
* crossing multiple mountpoints.
* Unlock vnodes and vmnts as we're going to recurse.
*/
unlock_vnode(dirp);
unlock_vnode(vp);
unlock_vmnt(dir_vmp);
old_wd = fp->fp_wd; /* Save orig. working dirp */
fp->fp_wd = dirp;
vp = new_node(resolve, oflags, bits);
fp->fp_wd = old_wd; /* Restore */
if (vp != NULL) {
put_vnode(dirp);
*(resolve->l_vnode) = vp;
return(vp);
}
r = err_code;
}
if (r == EEXIST)
err_code = EIO; /* Impossible, we have verified that
* the last component doesn't exist and
* is not a dangling symlink. */
else
err_code = r;
unlock_vnode(dirp);
unlock_vnode(vp);
unlock_vmnt(dir_vmp);
put_vnode(dirp);
return(NULL);
}
/* Store results and mark vnode in use */
vp->v_fs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_size = res.fsize;
vp->v_uid = res.uid;
vp->v_gid = res.gid;
vp->v_sdev = res.dev;
vp->v_vmnt = dirp->v_vmnt;
vp->v_dev = vp->v_vmnt->m_dev;
vp->v_fs_count = 1;
vp->v_ref_count = 1;
} else {
/* Either last component exists, or there is some other problem. */
if (vp != NULL) {
r = EEXIST; /* File exists or a symlink names a file while
* O_EXCL is set. */
} else
r = err_code; /* Other problem. */
}
err_code = r;
/* When dirp equals vp, we shouldn't release the lock as a vp is locked only
* once. Releasing the lock would cause the resulting vp not be locked and
* cause mayhem later on. */
if (dirp != vp) {
unlock_vnode(dirp);
}
unlock_vmnt(dir_vmp);
put_vnode(dirp);
*(resolve->l_vnode) = vp;
return(vp);
}
/*===========================================================================*
* do_pipe *
*===========================================================================*/
PUBLIC int do_pipe()
{
/* Perform the pipe(fil_des) system call. */
register struct fproc *rfp;
int r;
struct filp *fil_ptr0, *fil_ptr1;
int fil_des[2]; /* reply goes here */
struct vnode *vp;
struct vmnt *vmp;
struct node_details res;
/* See if a free vnode is available */
if ( (vp = get_free_vnode()) == NIL_VNODE) return(err_code);
/* Acquire two file descriptors. */
rfp = fp;
if ((r = get_fd(0, R_BIT, &fil_des[0], &fil_ptr0)) != OK) return(r);
rfp->fp_filp[fil_des[0]] = fil_ptr0;
FD_SET(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 1;
if ((r = get_fd(0, W_BIT, &fil_des[1], &fil_ptr1)) != OK) {
rfp->fp_filp[fil_des[0]] = NIL_FILP;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0;
return(r);
}
rfp->fp_filp[fil_des[1]] = fil_ptr1;
FD_SET(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 1;
/* Create a named pipe inode on PipeFS */
r = req_newnode(PFS_PROC_NR, fp->fp_effuid, fp->fp_effgid, I_NAMED_PIPE,
(dev_t) 0, &res);
if (r != OK) {
rfp->fp_filp[fil_des[0]] = NIL_FILP;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0;
rfp->fp_filp[fil_des[1]] = NIL_FILP;
FD_CLR(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 0;
return(r);
}
/* Fill in vnode */
vp->v_fs_e = res.fs_e;
vp->v_mapfs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mapinode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_pipe = I_PIPE;
vp->v_pipe_rd_pos= 0;
vp->v_pipe_wr_pos= 0;
vp->v_fs_count = 1;
vp->v_mapfs_count = 1;
vp->v_ref_count = 1;
vp->v_size = 0;
vp->v_vmnt = NIL_VMNT;
vp->v_dev = NO_DEV;
/* Fill in filp objects */
fil_ptr0->filp_vno = vp;
dup_vnode(vp);
fil_ptr1->filp_vno = vp;
fil_ptr0->filp_flags = O_RDONLY;
fil_ptr1->filp_flags = O_WRONLY;
m_out.reply_i1 = fil_des[0];
m_out.reply_i2 = fil_des[1];
return(OK);
}
/*===========================================================================*
* new_node *
*===========================================================================*/
PRIVATE struct vnode *new_node(int oflags, mode_t bits)
{
/* Try to create a new inode and return a pointer to it. If the inode already
exists, return a pointer to it as well, but set err_code accordingly.
NULL is returned if the path cannot be resolved up to the last
directory, or when the inode cannot be created due to permissions or
otherwise. */
struct vnode *dirp, *vp;
int r, flags;
struct node_details res;
/* When O_CREAT and O_EXCL flags are set, the path may not be named by a
* symbolic link. */
flags = PATH_NOFLAGS;
if (oflags & O_EXCL) flags |= PATH_RET_SYMLINK;
/* See if the path can be opened down to the last directory. */
if ((dirp = last_dir(fp)) == NULL) return(NULL);
/* The final directory is accessible. Get final component of the path. */
vp = advance(dirp, flags, fp);
/* The combination of a symlink with absolute path followed by a danglink
* symlink results in a new path that needs to be re-resolved entirely. */
if (user_fullpath[0] == '/') return new_node(oflags, bits);
if (vp == NULL && err_code == ENOENT) {
/* Last path component does not exist. Make a new directory entry. */
if ((vp = get_free_vnode()) == NULL) {
/* Can't create new vnode: out of vnodes. */
put_vnode(dirp);
return(NULL);
}
if ((r = forbidden(dirp, W_BIT|X_BIT)) != OK ||
(r = req_create(dirp->v_fs_e, dirp->v_inode_nr,bits, fp->fp_effuid,
fp->fp_effgid, user_fullpath, &res)) != OK ) {
/* Can't create inode either due to permissions or some other
* problem. In case r is EEXIST, we might be dealing with a
* dangling symlink.*/
if (r == EEXIST) {
struct vnode *slp, *old_wd;
/* Resolve path up to symlink */
slp = advance(dirp, PATH_RET_SYMLINK, fp);
if (slp != NULL) {
if (S_ISLNK(slp->v_mode)) {
/* Get contents of link */
int max_linklen;
max_linklen = sizeof(user_fullpath)-1;
r = req_rdlink(slp->v_fs_e,
slp->v_inode_nr,
VFS_PROC_NR,
user_fullpath,
max_linklen, 0);
if (r < 0) {
/* Failed to read link */
put_vnode(slp);
put_vnode(dirp);
err_code = r;
return(NULL);
}
user_fullpath[r] = '\0';/* Term. path*/
}
put_vnode(slp);
}
/* Try to create the inode the dangling symlink was
* pointing to. We have to use dirp as starting point
* as there might be multiple successive symlinks
* crossing multiple mountpoints. */
old_wd = fp->fp_wd; /* Save orig. working dirp */
fp->fp_wd = dirp;
vp = new_node(oflags, bits);
fp->fp_wd = old_wd; /* Restore */
if (vp != NULL) {
put_vnode(dirp);
return(vp);
}
r = err_code;
}
if (r == EEXIST)
err_code = EIO; /* Impossible, we have verified that
* the last component doesn't exist and
* is not a dangling symlink. */
else
err_code = r;
put_vnode(dirp);
return(NULL);
}
/* Store results and mark vnode in use */
vp->v_fs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_size = res.fsize;
vp->v_uid = res.uid;
vp->v_gid = res.gid;
vp->v_sdev = res.dev;
vp->v_vmnt = dirp->v_vmnt;
vp->v_dev = vp->v_vmnt->m_dev;
vp->v_fs_count = 1;
vp->v_ref_count = 1;
} else {
/* Either last component exists, or there is some other problem. */
if (vp != NULL)
r = EEXIST; /* File exists or a symlink names a file while
* O_EXCL is set. */
else
r = err_code; /* Other problem. */
}
err_code = r;
put_vnode(dirp);
return(vp);
}
/*===========================================================================*
* do_pipe *
*===========================================================================*/
int do_pipe()
{
/* Perform the pipe(fil_des) system call. */
register struct fproc *rfp;
int r;
struct filp *fil_ptr0, *fil_ptr1;
int fil_des[2]; /* reply goes here */
struct vnode *vp;
struct vmnt *vmp;
struct node_details res;
/* Get a lock on PFS */
if ((vmp = find_vmnt(PFS_PROC_NR)) == NULL) panic("PFS gone");
if ((r = lock_vmnt(vmp, VMNT_READ)) != OK) return(r);
/* See if a free vnode is available */
if ((vp = get_free_vnode()) == NULL) {
unlock_vmnt(vmp);
return(err_code);
}
lock_vnode(vp, VNODE_OPCL);
/* Acquire two file descriptors. */
rfp = fp;
if ((r = get_fd(0, R_BIT, &fil_des[0], &fil_ptr0)) != OK) {
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
rfp->fp_filp[fil_des[0]] = fil_ptr0;
FD_SET(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 1; /* mark filp in use */
if ((r = get_fd(0, W_BIT, &fil_des[1], &fil_ptr1)) != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0; /* mark filp free */
unlock_filp(fil_ptr0);
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
rfp->fp_filp[fil_des[1]] = fil_ptr1;
FD_SET(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 1;
/* Create a named pipe inode on PipeFS */
r = req_newnode(PFS_PROC_NR, fp->fp_effuid, fp->fp_effgid, I_NAMED_PIPE,
NO_DEV, &res);
if (r != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0;
rfp->fp_filp[fil_des[1]] = NULL;
FD_CLR(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 0;
unlock_filp(fil_ptr1);
unlock_filp(fil_ptr0);
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
/* Fill in vnode */
vp->v_fs_e = res.fs_e;
vp->v_mapfs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mapinode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_fs_count = 1;
vp->v_mapfs_count = 1;
vp->v_ref_count = 1;
vp->v_size = 0;
vp->v_vmnt = NULL;
vp->v_dev = NO_DEV;
/* Fill in filp objects */
fil_ptr0->filp_vno = vp;
dup_vnode(vp);
fil_ptr1->filp_vno = vp;
fil_ptr0->filp_flags = O_RDONLY;
fil_ptr1->filp_flags = O_WRONLY;
m_out.reply_i1 = fil_des[0];
m_out.reply_i2 = fil_des[1];
unlock_filps(fil_ptr0, fil_ptr1);
unlock_vmnt(vmp);
return(OK);
}
/*===========================================================================*
* do_pipe *
*===========================================================================*/
PUBLIC int do_pipe()
{
/* Perform the pipe(fil_des) system call. */
register struct fproc *rfp;
int r;
struct filp *fil_ptr0, *fil_ptr1;
int fil_des[2]; /* reply goes here */
struct vnode *vp;
struct node_details res;
/* See if a free vnode is available */
if ( (vp = get_free_vnode()) == NULL) return(err_code);
/* Acquire two file descriptors. */
rfp = fp;
/* Check if process can open 2 more files */
if(rfp->fp_openfd + 1 >= (unsigned int)rfp->fp_nofilelim.rlim_cur && rfp->fp_nofilelim.rlim_cur != RLIM_INFINITY)
return(EMFILE);
if ((r = get_fd(0, R_BIT, &fil_des[0], &fil_ptr0)) != OK) return(r);
rfp->fp_filp[fil_des[0]] = fil_ptr0;
FD_SET(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 1;
if ((r = get_fd(0, W_BIT, &fil_des[1], &fil_ptr1)) != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0;
return(r);
}
rfp->fp_filp[fil_des[1]] = fil_ptr1;
FD_SET(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 1;
/* Create a named pipe inode on PipeFS */
r = req_newnode(PFS_PROC_NR, fp->fp_effuid, fp->fp_effgid, I_NAMED_PIPE,
NO_DEV, &res);
if (r != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
FD_CLR(fil_des[0], &rfp->fp_filp_inuse);
fil_ptr0->filp_count = 0;
rfp->fp_filp[fil_des[1]] = NULL;
FD_CLR(fil_des[1], &rfp->fp_filp_inuse);
fil_ptr1->filp_count = 0;
return(r);
}
/* 2 new files openned */
rfp->fp_openfd+=2;
/* Fill in vnode */
vp->v_fs_e = res.fs_e;
vp->v_mapfs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mapinode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_pipe = I_PIPE;
vp->v_pipe_rd_pos= 0;
vp->v_pipe_wr_pos= 0;
vp->v_fs_count = 1;
vp->v_mapfs_count = 1;
vp->v_ref_count = 1;
vp->v_size = 0;
vp->v_vmnt = NULL;
vp->v_dev = NO_DEV;
/* Fill in filp objects */
fil_ptr0->filp_vno = vp;
dup_vnode(vp);
fil_ptr1->filp_vno = vp;
fil_ptr0->filp_flags = O_RDONLY;
fil_ptr1->filp_flags = O_WRONLY;
m_out.reply_i1 = fil_des[0];
m_out.reply_i2 = fil_des[1];
return(OK);
}
/*===========================================================================*
* create_pipe *
*===========================================================================*/
static int create_pipe(int fil_des[2], int flags)
{
register struct fproc *rfp;
int r;
struct filp *fil_ptr0, *fil_ptr1;
struct vnode *vp;
struct vmnt *vmp;
struct node_details res;
/* Get a lock on PFS */
if ((vmp = find_vmnt(PFS_PROC_NR)) == NULL) panic("PFS gone");
if ((r = lock_vmnt(vmp, VMNT_READ)) != OK) return(r);
/* See if a free vnode is available */
if ((vp = get_free_vnode()) == NULL) {
unlock_vmnt(vmp);
return(err_code);
}
lock_vnode(vp, VNODE_OPCL);
/* Acquire two file descriptors. */
rfp = fp;
if ((r = get_fd(fp, 0, R_BIT, &fil_des[0], &fil_ptr0)) != OK) {
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
rfp->fp_filp[fil_des[0]] = fil_ptr0;
fil_ptr0->filp_count = 1; /* mark filp in use */
if ((r = get_fd(fp, 0, W_BIT, &fil_des[1], &fil_ptr1)) != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
fil_ptr0->filp_count = 0; /* mark filp free */
unlock_filp(fil_ptr0);
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
rfp->fp_filp[fil_des[1]] = fil_ptr1;
fil_ptr1->filp_count = 1;
/* Create a named pipe inode on PipeFS */
r = req_newnode(PFS_PROC_NR, fp->fp_effuid, fp->fp_effgid, I_NAMED_PIPE,
NO_DEV, &res);
if (r != OK) {
rfp->fp_filp[fil_des[0]] = NULL;
fil_ptr0->filp_count = 0;
rfp->fp_filp[fil_des[1]] = NULL;
fil_ptr1->filp_count = 0;
unlock_filp(fil_ptr1);
unlock_filp(fil_ptr0);
unlock_vnode(vp);
unlock_vmnt(vmp);
return(r);
}
/* Fill in vnode */
vp->v_fs_e = res.fs_e;
vp->v_mapfs_e = res.fs_e;
vp->v_inode_nr = res.inode_nr;
vp->v_mapinode_nr = res.inode_nr;
vp->v_mode = res.fmode;
vp->v_fs_count = 1;
vp->v_mapfs_count = 1;
vp->v_ref_count = 1;
vp->v_size = 0;
vp->v_vmnt = NULL;
vp->v_dev = NO_DEV;
/* Fill in filp objects */
fil_ptr0->filp_vno = vp;
dup_vnode(vp);
fil_ptr1->filp_vno = vp;
fil_ptr0->filp_flags = O_RDONLY | (flags & ~O_ACCMODE);
fil_ptr1->filp_flags = O_WRONLY | (flags & ~O_ACCMODE);
if (flags & O_CLOEXEC) {
FD_SET(fil_des[0], &rfp->fp_cloexec_set);
FD_SET(fil_des[1], &rfp->fp_cloexec_set);
}
unlock_filps(fil_ptr0, fil_ptr1);
unlock_vmnt(vmp);
return(OK);
}
/*===========================================================================*
* 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);
}
/*===========================================================================*
* 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);
}
