551 lines
17 KiB
C
551 lines
17 KiB
C
/* When a needed block is not in the cache, it must be fetched from the disk.
|
|
* Special character files also require I/O. The routines for these are here.
|
|
*
|
|
* The entry points in this file are:
|
|
* dev_open: FS opens a device
|
|
* dev_close: FS closes a device
|
|
* dev_io: FS does a read or write on a device
|
|
* dev_status: FS processes callback request alert
|
|
* gen_opcl: generic call to a task to perform an open/close
|
|
* gen_io: generic call to a task to perform an I/O operation
|
|
* no_dev: open/close processing for devices that don't exist
|
|
* no_dev_io: i/o processing for devices that don't exist
|
|
* tty_opcl: perform tty-specific processing for open/close
|
|
* ctty_opcl: perform controlling-tty-specific processing for open/close
|
|
* ctty_io: perform controlling-tty-specific processing for I/O
|
|
* do_ioctl: perform the IOCTL system call
|
|
* do_setsid: perform the SETSID system call (FS side)
|
|
*/
|
|
|
|
#include "fs.h"
|
|
#include <fcntl.h>
|
|
#include <minix/callnr.h>
|
|
#include <minix/com.h>
|
|
#include "file.h"
|
|
#include "fproc.h"
|
|
#include "inode.h"
|
|
#include "param.h"
|
|
#include "super.h"
|
|
|
|
#define ELEMENTS(a) (sizeof(a)/sizeof((a)[0]))
|
|
|
|
extern int dmap_size;
|
|
|
|
/*===========================================================================*
|
|
* dev_open *
|
|
*===========================================================================*/
|
|
PUBLIC int dev_open(dev, proc, flags)
|
|
dev_t dev; /* device to open */
|
|
int proc; /* process to open for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
int major, r;
|
|
struct dmap *dp;
|
|
|
|
/* Determine the major device number call the device class specific
|
|
* open/close routine. (This is the only routine that must check the
|
|
* device number for being in range. All others can trust this check.)
|
|
*/
|
|
major = (dev >> MAJOR) & BYTE;
|
|
if (major >= NR_DEVICES) major = 0;
|
|
dp = &dmap[major];
|
|
if (dp->dmap_driver == NONE) {
|
|
printf("FS: open: no driver for dev %x\n", dev);
|
|
return EIO;
|
|
}
|
|
r = (*dp->dmap_opcl)(DEV_OPEN, dev, proc, flags);
|
|
if (r == SUSPEND) panic(__FILE__,"suspend on open from", dp->dmap_driver);
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* dev_close *
|
|
*===========================================================================*/
|
|
PUBLIC void dev_close(dev)
|
|
dev_t dev; /* device to close */
|
|
{
|
|
/* See if driver is roughly valid. */
|
|
if (dmap[(dev >> MAJOR)].dmap_driver == NONE) {
|
|
return;
|
|
}
|
|
(void) (*dmap[(dev >> MAJOR) & BYTE].dmap_opcl)(DEV_CLOSE, dev, 0, 0);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* dev_status *
|
|
*===========================================================================*/
|
|
PUBLIC void dev_status(message *m)
|
|
{
|
|
message st;
|
|
int d, get_more = 1;
|
|
|
|
for(d = 0; d < NR_DEVICES; d++)
|
|
if (dmap[d].dmap_driver != NONE &&
|
|
dmap[d].dmap_driver == m->m_source)
|
|
break;
|
|
|
|
if (d >= NR_DEVICES)
|
|
return;
|
|
|
|
do {
|
|
int r;
|
|
st.m_type = DEV_STATUS;
|
|
if ((r=sendrec(m->m_source, &st)) != OK) {
|
|
printf("DEV_STATUS failed to %d: %d\n", m->m_source, r);
|
|
if (r == EDEADSRCDST) return;
|
|
if (r == EDSTDIED) return;
|
|
if (r == ESRCDIED) return;
|
|
panic(__FILE__,"couldn't sendrec for DEV_STATUS", r);
|
|
}
|
|
|
|
switch(st.m_type) {
|
|
case DEV_REVIVE:
|
|
revive(st.REP_PROC_NR, st.REP_STATUS);
|
|
break;
|
|
case DEV_IO_READY:
|
|
select_notified(d, st.DEV_MINOR, st.DEV_SEL_OPS);
|
|
break;
|
|
default:
|
|
printf("FS: unrecognized reply %d to DEV_STATUS\n", st.m_type);
|
|
/* Fall through. */
|
|
case DEV_NO_STATUS:
|
|
get_more = 0;
|
|
break;
|
|
}
|
|
} while(get_more);
|
|
|
|
return;
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* dev_io *
|
|
*===========================================================================*/
|
|
PUBLIC int dev_io(op, dev, proc, buf, pos, bytes, flags)
|
|
int op; /* DEV_READ, DEV_WRITE, DEV_IOCTL, etc. */
|
|
dev_t dev; /* major-minor device number */
|
|
int proc; /* in whose address space is buf? */
|
|
void *buf; /* virtual address of the buffer */
|
|
off_t pos; /* byte position */
|
|
int bytes; /* how many bytes to transfer */
|
|
int flags; /* special flags, like O_NONBLOCK */
|
|
{
|
|
/* Read or write from a device. The parameter 'dev' tells which one. */
|
|
struct dmap *dp;
|
|
message dev_mess;
|
|
|
|
/* Determine task dmap. */
|
|
dp = &dmap[(dev >> MAJOR) & BYTE];
|
|
|
|
/* See if driver is roughly valid. */
|
|
if (dp->dmap_driver == NONE) {
|
|
printf("FS: dev_io: no driver for dev %x\n", dev);
|
|
return EIO;
|
|
}
|
|
|
|
/* Set up the message passed to task. */
|
|
dev_mess.m_type = op;
|
|
dev_mess.DEVICE = (dev >> MINOR) & BYTE;
|
|
dev_mess.POSITION = pos;
|
|
dev_mess.PROC_NR = proc;
|
|
dev_mess.ADDRESS = buf;
|
|
dev_mess.COUNT = bytes;
|
|
dev_mess.TTY_FLAGS = flags;
|
|
|
|
/* Call the task. */
|
|
(*dp->dmap_io)(dp->dmap_driver, &dev_mess);
|
|
|
|
/* Task has completed. See if call completed. */
|
|
if (dev_mess.REP_STATUS == SUSPEND) {
|
|
if (flags & O_NONBLOCK) {
|
|
/* Not supposed to block. */
|
|
dev_mess.m_type = CANCEL;
|
|
dev_mess.PROC_NR = proc;
|
|
dev_mess.DEVICE = (dev >> MINOR) & BYTE;
|
|
(*dp->dmap_io)(dp->dmap_driver, &dev_mess);
|
|
if (dev_mess.REP_STATUS == EINTR) dev_mess.REP_STATUS = EAGAIN;
|
|
} else {
|
|
/* Suspend user. */
|
|
suspend(dp->dmap_driver);
|
|
return(SUSPEND);
|
|
}
|
|
}
|
|
return(dev_mess.REP_STATUS);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* gen_opcl *
|
|
*===========================================================================*/
|
|
PUBLIC int gen_opcl(op, dev, proc, flags)
|
|
int op; /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev; /* device to open or close */
|
|
int proc; /* process to open/close for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
/* Called from the dmap struct in table.c on opens & closes of special files.*/
|
|
struct dmap *dp;
|
|
message dev_mess;
|
|
|
|
/* Determine task dmap. */
|
|
dp = &dmap[(dev >> MAJOR) & BYTE];
|
|
|
|
dev_mess.m_type = op;
|
|
dev_mess.DEVICE = (dev >> MINOR) & BYTE;
|
|
dev_mess.PROC_NR = proc;
|
|
dev_mess.COUNT = flags;
|
|
|
|
/* Call the task. */
|
|
(*dp->dmap_io)(dp->dmap_driver, &dev_mess);
|
|
|
|
return(dev_mess.REP_STATUS);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* tty_opcl *
|
|
*===========================================================================*/
|
|
PUBLIC int tty_opcl(op, dev, proc, flags)
|
|
int op; /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev; /* device to open or close */
|
|
int proc; /* process to open/close for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
/* This procedure is called from the dmap struct on tty open/close. */
|
|
|
|
int r;
|
|
register struct fproc *rfp;
|
|
|
|
/* Add O_NOCTTY to the flags if this process is not a session leader, or
|
|
* if it already has a controlling tty, or if it is someone elses
|
|
* controlling tty.
|
|
*/
|
|
if (!fp->fp_sesldr || fp->fp_tty != 0) {
|
|
flags |= O_NOCTTY;
|
|
} else {
|
|
for (rfp = &fproc[0]; rfp < &fproc[NR_PROCS]; rfp++) {
|
|
if (rfp->fp_tty == dev) flags |= O_NOCTTY;
|
|
}
|
|
}
|
|
|
|
r = gen_opcl(op, dev, proc, flags);
|
|
|
|
/* Did this call make the tty the controlling tty? */
|
|
if (r == 1) {
|
|
fp->fp_tty = dev;
|
|
r = OK;
|
|
}
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* ctty_opcl *
|
|
*===========================================================================*/
|
|
PUBLIC int ctty_opcl(op, dev, proc, flags)
|
|
int op; /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev; /* device to open or close */
|
|
int proc; /* process to open/close for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
/* This procedure is called from the dmap struct in table.c on opening/closing
|
|
* /dev/tty, the magic device that translates to the controlling tty.
|
|
*/
|
|
|
|
return(fp->fp_tty == 0 ? ENXIO : OK);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_setsid *
|
|
*===========================================================================*/
|
|
PUBLIC int do_setsid()
|
|
{
|
|
/* Perform the FS side of the SETSID call, i.e. get rid of the controlling
|
|
* terminal of a process, and make the process a session leader.
|
|
*/
|
|
register struct fproc *rfp;
|
|
|
|
/* Only MM may do the SETSID call directly. */
|
|
if (who != PM_PROC_NR) return(ENOSYS);
|
|
|
|
/* Make the process a session leader with no controlling tty. */
|
|
rfp = &fproc[m_in.slot1];
|
|
rfp->fp_sesldr = TRUE;
|
|
rfp->fp_tty = 0;
|
|
return(OK);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_ioctl *
|
|
*===========================================================================*/
|
|
PUBLIC int do_ioctl()
|
|
{
|
|
/* Perform the ioctl(ls_fd, request, argx) system call (uses m2 fmt). */
|
|
|
|
struct filp *f;
|
|
register struct inode *rip;
|
|
dev_t dev;
|
|
|
|
if ( (f = get_filp(m_in.ls_fd)) == NIL_FILP) return(err_code);
|
|
rip = f->filp_ino; /* get inode pointer */
|
|
if ( (rip->i_mode & I_TYPE) != I_CHAR_SPECIAL
|
|
&& (rip->i_mode & I_TYPE) != I_BLOCK_SPECIAL) return(ENOTTY);
|
|
dev = (dev_t) rip->i_zone[0];
|
|
|
|
#if ENABLE_BINCOMPAT
|
|
if ((m_in.TTY_REQUEST >> 8) == 't') {
|
|
/* Obsolete sgtty ioctl, message contains more than is sane. */
|
|
struct dmap *dp;
|
|
message dev_mess;
|
|
|
|
dp = &dmap[(dev >> MAJOR) & BYTE];
|
|
|
|
dev_mess = m; /* Copy full message with all the weird bits. */
|
|
dev_mess.m_type = DEV_IOCTL;
|
|
dev_mess.PROC_NR = who;
|
|
dev_mess.TTY_LINE = (dev >> MINOR) & BYTE;
|
|
|
|
/* Call the task. */
|
|
(*dp->dmap_io)(dp->dmap_driver, &dev_mess);
|
|
|
|
m_out.TTY_SPEK = dev_mess.TTY_SPEK; /* erase and kill */
|
|
m_out.TTY_FLAGS = dev_mess.TTY_FLAGS; /* flags */
|
|
return(dev_mess.REP_STATUS);
|
|
}
|
|
#endif
|
|
|
|
return(dev_io(DEV_IOCTL, dev, who, m_in.ADDRESS, 0L,
|
|
m_in.REQUEST, f->filp_flags));
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* gen_io *
|
|
*===========================================================================*/
|
|
PUBLIC void gen_io(task_nr, mess_ptr)
|
|
int task_nr; /* which task to call */
|
|
message *mess_ptr; /* pointer to message for task */
|
|
{
|
|
/* All file system I/O ultimately comes down to I/O on major/minor device
|
|
* pairs. These lead to calls on the following routines via the dmap table.
|
|
*/
|
|
|
|
int r, proc_nr;
|
|
message local_m;
|
|
|
|
proc_nr = mess_ptr->PROC_NR;
|
|
if (! isokprocnr(proc_nr)) {
|
|
printf("FS: warning, got illegal process number (%d) from %d\n",
|
|
mess_ptr->PROC_NR, mess_ptr->m_source);
|
|
return;
|
|
}
|
|
|
|
while ((r = sendrec(task_nr, mess_ptr)) == ELOCKED) {
|
|
/* sendrec() failed to avoid deadlock. The task 'task_nr' is
|
|
* trying to send a REVIVE message for an earlier request.
|
|
* Handle it and go try again.
|
|
*/
|
|
if ((r = receive(task_nr, &local_m)) != OK) {
|
|
break;
|
|
}
|
|
|
|
/* If we're trying to send a cancel message to a task which has just
|
|
* sent a completion reply, ignore the reply and abort the cancel
|
|
* request. The caller will do the revive for the process.
|
|
*/
|
|
if (mess_ptr->m_type == CANCEL && local_m.REP_PROC_NR == proc_nr) {
|
|
return;
|
|
}
|
|
|
|
/* Otherwise it should be a REVIVE. */
|
|
if (local_m.m_type != REVIVE) {
|
|
printf(
|
|
"fs: strange device reply from %d, type = %d, proc = %d (1)\n",
|
|
local_m.m_source,
|
|
local_m.m_type, local_m.REP_PROC_NR);
|
|
continue;
|
|
}
|
|
|
|
revive(local_m.REP_PROC_NR, local_m.REP_STATUS);
|
|
}
|
|
|
|
/* The message received may be a reply to this call, or a REVIVE for some
|
|
* other process.
|
|
*/
|
|
for (;;) {
|
|
if (r != OK) {
|
|
if (r == EDEADSRCDST) return; /* give up */
|
|
if (r == EDSTDIED) return;
|
|
if (r == ESRCDIED) return;
|
|
if (r == ELOCKED) return;
|
|
else panic(__FILE__,"call_task: can't send/receive", r);
|
|
}
|
|
|
|
/* Did the process we did the sendrec() for get a result? */
|
|
if (mess_ptr->REP_PROC_NR == proc_nr) {
|
|
break;
|
|
} else if (mess_ptr->m_type == REVIVE) {
|
|
/* Otherwise it should be a REVIVE. */
|
|
revive(mess_ptr->REP_PROC_NR, mess_ptr->REP_STATUS);
|
|
} else {
|
|
printf(
|
|
"fs: strange device reply from %d, type = %d, proc = %d (2)\n",
|
|
mess_ptr->m_source,
|
|
mess_ptr->m_type, mess_ptr->REP_PROC_NR);
|
|
return;
|
|
}
|
|
|
|
r = receive(task_nr, mess_ptr);
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* ctty_io *
|
|
*===========================================================================*/
|
|
PUBLIC void ctty_io(task_nr, mess_ptr)
|
|
int task_nr; /* not used - for compatibility with dmap_t */
|
|
message *mess_ptr; /* pointer to message for task */
|
|
{
|
|
/* This routine is only called for one device, namely /dev/tty. Its job
|
|
* is to change the message to use the controlling terminal, instead of the
|
|
* major/minor pair for /dev/tty itself.
|
|
*/
|
|
|
|
struct dmap *dp;
|
|
|
|
if (fp->fp_tty == 0) {
|
|
/* No controlling tty present anymore, return an I/O error. */
|
|
mess_ptr->REP_STATUS = EIO;
|
|
} else {
|
|
/* Substitute the controlling terminal device. */
|
|
dp = &dmap[(fp->fp_tty >> MAJOR) & BYTE];
|
|
mess_ptr->DEVICE = (fp->fp_tty >> MINOR) & BYTE;
|
|
(*dp->dmap_io)(dp->dmap_driver, mess_ptr);
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* no_dev *
|
|
*===========================================================================*/
|
|
PUBLIC int no_dev(op, dev, proc, flags)
|
|
int op; /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev; /* device to open or close */
|
|
int proc; /* process to open/close for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
/* Called when opening a nonexistent device. */
|
|
return(ENODEV);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* no_dev_io *
|
|
*===========================================================================*/
|
|
PUBLIC void no_dev_io(int proc, message *m)
|
|
{
|
|
/* Called when doing i/o on a nonexistent device. */
|
|
printf("FS: I/O on unmapped device number\n");
|
|
return;
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* clone_opcl *
|
|
*===========================================================================*/
|
|
PUBLIC int clone_opcl(op, dev, proc, flags)
|
|
int op; /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev; /* device to open or close */
|
|
int proc; /* process to open/close for */
|
|
int flags; /* mode bits and flags */
|
|
{
|
|
/* Some devices need special processing upon open. Such a device is "cloned",
|
|
* i.e. on a succesful open it is replaced by a new device with a new unique
|
|
* minor device number. This new device number identifies a new object (such
|
|
* as a new network connection) that has been allocated within a task.
|
|
*/
|
|
struct dmap *dp;
|
|
int minor;
|
|
message dev_mess;
|
|
|
|
/* Determine task dmap. */
|
|
dp = &dmap[(dev >> MAJOR) & BYTE];
|
|
minor = (dev >> MINOR) & BYTE;
|
|
|
|
dev_mess.m_type = op;
|
|
dev_mess.DEVICE = minor;
|
|
dev_mess.PROC_NR = proc;
|
|
dev_mess.COUNT = flags;
|
|
|
|
/* Call the task. */
|
|
(*dp->dmap_io)(dp->dmap_driver, &dev_mess);
|
|
|
|
if (op == DEV_OPEN && dev_mess.REP_STATUS >= 0) {
|
|
if (dev_mess.REP_STATUS != minor) {
|
|
/* A new minor device number has been returned. Create a
|
|
* temporary device file to hold it.
|
|
*/
|
|
struct inode *ip;
|
|
|
|
/* Device number of the new device. */
|
|
dev = (dev & ~(BYTE << MINOR)) | (dev_mess.REP_STATUS << MINOR);
|
|
|
|
ip = alloc_inode(root_dev, ALL_MODES | I_CHAR_SPECIAL);
|
|
if (ip == NIL_INODE) {
|
|
/* Oops, that didn't work. Undo open. */
|
|
(void) clone_opcl(DEV_CLOSE, dev, proc, 0);
|
|
return(err_code);
|
|
}
|
|
ip->i_zone[0] = dev;
|
|
|
|
put_inode(fp->fp_filp[m_in.fd]->filp_ino);
|
|
fp->fp_filp[m_in.fd]->filp_ino = ip;
|
|
}
|
|
dev_mess.REP_STATUS = OK;
|
|
}
|
|
return(dev_mess.REP_STATUS);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* dev_up *
|
|
*===========================================================================*/
|
|
PUBLIC void dev_up(int maj)
|
|
{
|
|
/* A new device driver has been mapped in. This function
|
|
* checks if any filesystems are mounted on it, and if so,
|
|
* dev_open()s them so the filesystem can be reused.
|
|
*/
|
|
struct super_block *sb;
|
|
struct filp *fp;
|
|
int r;
|
|
|
|
/* Open a device once for every filp that's opened on it,
|
|
* and once for every filesystem mounted from it.
|
|
*/
|
|
|
|
for(sb = super_block; sb < &super_block[NR_SUPERS]; sb++) {
|
|
int minor;
|
|
if(sb->s_dev == NO_DEV)
|
|
continue;
|
|
if(((sb->s_dev >> MAJOR) & BYTE) != maj)
|
|
continue;
|
|
minor = ((sb->s_dev >> MINOR) & BYTE);
|
|
printf("FS: remounting dev %d/%d\n", maj, minor);
|
|
if((r = dev_open(sb->s_dev, FS_PROC_NR,
|
|
sb->s_rd_only ? R_BIT : (R_BIT|W_BIT))) != OK) {
|
|
printf("FS: mounted dev %d/%d re-open failed: %d.\n",
|
|
maj, minor, r);
|
|
}
|
|
}
|
|
|
|
for(fp = filp; fp < &filp[NR_FILPS]; fp++) {
|
|
struct inode *in;
|
|
int minor;
|
|
if(fp->filp_count < 1 || !(in=fp->filp_ino)) continue;
|
|
if(((in->i_zone[0] >> MAJOR) & BYTE) != maj) continue;
|
|
if(!(in->i_mode & (I_BLOCK_SPECIAL|I_CHAR_SPECIAL))) continue;
|
|
|
|
minor = ((in->i_zone[0] >> MINOR) & BYTE);
|
|
|
|
if((r = dev_open(in->i_dev, FS_PROC_NR,
|
|
in->i_mode & (R_BIT|W_BIT))) != OK) {
|
|
printf("FS: file on dev %d/%d re-open failed: %d.\n",
|
|
maj, minor, r);
|
|
}
|
|
}
|
|
|
|
return;
|
|
}
|
|
|