339 lines
9.6 KiB
C
339 lines
9.6 KiB
C
#include "inc.h"
|
|
#include <minix/vfsif.h>
|
|
|
|
PRIVATE int dummyproc;
|
|
|
|
FORWARD _PROTOTYPE( int safe_io_conversion, (endpoint_t, cp_grant_id_t *,
|
|
int *, cp_grant_id_t *, int,
|
|
endpoint_t *, void **, int *,
|
|
vir_bytes));
|
|
FORWARD _PROTOTYPE( void safe_io_cleanup, (cp_grant_id_t, cp_grant_id_t *,
|
|
int));
|
|
FORWARD _PROTOTYPE( int gen_opcl, (endpoint_t driver_e, int op,
|
|
dev_t dev, int proc_e, int flags));
|
|
FORWARD _PROTOTYPE( int gen_io, (endpoint_t task_nr, message *mess_ptr));
|
|
|
|
|
|
/*===========================================================================*
|
|
* fs_new_driver *
|
|
*===========================================================================*/
|
|
PUBLIC int fs_new_driver(void)
|
|
{
|
|
/* New driver endpoint for this device */
|
|
driver_endpoints[(fs_m_in.REQ_DEV >> MAJOR) & BYTE].driver_e =
|
|
fs_m_in.REQ_DRIVER_E;
|
|
return(OK);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* safe_io_conversion *
|
|
*===========================================================================*/
|
|
PRIVATE int safe_io_conversion(driver, gid, op, gids, gids_size,
|
|
io_ept, buf, vec_grants, bytes)
|
|
endpoint_t driver;
|
|
cp_grant_id_t *gid;
|
|
int *op;
|
|
cp_grant_id_t *gids;
|
|
int gids_size;
|
|
endpoint_t *io_ept;
|
|
void **buf;
|
|
int *vec_grants;
|
|
vir_bytes bytes;
|
|
{
|
|
int j;
|
|
iovec_t *v;
|
|
static iovec_t new_iovec[NR_IOREQS];
|
|
|
|
/* Number of grants allocated in vector I/O. */
|
|
*vec_grants = 0;
|
|
|
|
/* Driver can handle it - change request to a safe one. */
|
|
|
|
*gid = GRANT_INVALID;
|
|
|
|
switch(*op) {
|
|
case MFS_DEV_READ:
|
|
case MFS_DEV_WRITE:
|
|
/* Change to safe op. */
|
|
*op = *op == MFS_DEV_READ ? DEV_READ_S : DEV_WRITE_S;
|
|
|
|
if((*gid=cpf_grant_direct(driver, (vir_bytes) *buf,
|
|
bytes, *op == DEV_READ_S ? CPF_WRITE :
|
|
CPF_READ)) < 0) {
|
|
panic("cpf_grant_magic of buffer failed");
|
|
}
|
|
|
|
break;
|
|
case MFS_DEV_GATHER:
|
|
case MFS_DEV_SCATTER:
|
|
/* Change to safe op. */
|
|
*op = *op == MFS_DEV_GATHER ?
|
|
DEV_GATHER_S : DEV_SCATTER_S;
|
|
|
|
/* Grant access to my new i/o vector. */
|
|
if((*gid = cpf_grant_direct(driver,
|
|
(vir_bytes) new_iovec, bytes * sizeof(iovec_t),
|
|
CPF_READ | CPF_WRITE)) < 0) {
|
|
panic("cpf_grant_direct of vector failed");
|
|
}
|
|
v = (iovec_t *) *buf;
|
|
/* Grant access to i/o buffers. */
|
|
for(j = 0; j < bytes; j++) {
|
|
if(j >= NR_IOREQS)
|
|
panic("vec too big: %d", bytes);
|
|
new_iovec[j].iov_addr = gids[j] =
|
|
cpf_grant_direct(driver, (vir_bytes)
|
|
v[j].iov_addr, v[j].iov_size,
|
|
*op == DEV_GATHER_S ? CPF_WRITE : CPF_READ);
|
|
if(!GRANT_VALID(gids[j])) {
|
|
panic("mfs: grant to iovec buf failed");
|
|
}
|
|
new_iovec[j].iov_size = v[j].iov_size;
|
|
(*vec_grants)++;
|
|
}
|
|
|
|
/* Set user's vector to the new one. */
|
|
*buf = new_iovec;
|
|
break;
|
|
}
|
|
|
|
/* If we have converted to a safe operation, I/O
|
|
* endpoint becomes FS if it wasn't already.
|
|
*/
|
|
if(GRANT_VALID(*gid)) {
|
|
*io_ept = SELF_E;
|
|
return 1;
|
|
}
|
|
|
|
/* Not converted to a safe operation (because there is no
|
|
* copying involved in this operation).
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* safe_io_cleanup *
|
|
*===========================================================================*/
|
|
PRIVATE void safe_io_cleanup(gid, gids, gids_size)
|
|
cp_grant_id_t gid;
|
|
cp_grant_id_t *gids;
|
|
int gids_size;
|
|
{
|
|
/* Free resources (specifically, grants) allocated by safe_io_conversion(). */
|
|
int j;
|
|
|
|
cpf_revoke(gid);
|
|
|
|
for(j = 0; j < gids_size; j++)
|
|
cpf_revoke(gids[j]);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* dev_open *
|
|
*===========================================================================*/
|
|
PUBLIC int dev_open(
|
|
endpoint_t driver_e,
|
|
dev_t dev, /* device to open */
|
|
int proc, /* process to open for */
|
|
int flags /* mode bits and flags */
|
|
)
|
|
{
|
|
int major, r;
|
|
|
|
/* 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;
|
|
r = gen_opcl(driver_e, DEV_OPEN, dev, proc, flags);
|
|
if (r == SUSPEND) panic("suspend on open from");
|
|
return(r);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* block_dev_io *
|
|
*===========================================================================*/
|
|
PUBLIC int block_dev_io(
|
|
int op, /* MFS_DEV_READ, MFS_DEV_WRITE, etc. */
|
|
dev_t dev, /* major-minor device number */
|
|
int proc_e, /* in whose address space is buf? */
|
|
void *buf, /* virtual address of the buffer */
|
|
u64_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. */
|
|
int r, safe;
|
|
message m;
|
|
cp_grant_id_t gid = GRANT_INVALID;
|
|
int vec_grants;
|
|
int op_used;
|
|
void *buf_used;
|
|
static cp_grant_id_t gids[NR_IOREQS];
|
|
endpoint_t driver_e;
|
|
|
|
/* Determine driver endpoint for this device */
|
|
driver_e = driver_endpoints[(dev >> MAJOR) & BYTE].driver_e;
|
|
|
|
/* See if driver is roughly valid. */
|
|
if (driver_e == NONE) return(EDEADSRCDST);
|
|
|
|
/* The io vector copying relies on this I/O being for FS itself. */
|
|
if(proc_e != SELF_E) {
|
|
printf("ISOFS(%d) doing block_dev_io for non-self %d\n", SELF_E, proc_e);
|
|
panic("doing block_dev_io for non-self: %d", proc_e);
|
|
}
|
|
|
|
/* By default, these are right. */
|
|
m.IO_ENDPT = proc_e;
|
|
m.ADDRESS = buf;
|
|
buf_used = buf;
|
|
|
|
/* Convert parameters to 'safe mode'. */
|
|
op_used = op;
|
|
safe = safe_io_conversion(driver_e, &gid,
|
|
&op_used, gids, NR_IOREQS, &m.IO_ENDPT, &buf_used,
|
|
&vec_grants, bytes);
|
|
|
|
/* Set up rest of the message. */
|
|
if (safe) m.IO_GRANT = (char *) gid;
|
|
|
|
m.m_type = op_used;
|
|
m.DEVICE = (dev >> MINOR) & BYTE;
|
|
m.POSITION = ex64lo(pos);
|
|
m.COUNT = bytes;
|
|
m.HIGHPOS = ex64hi(pos);
|
|
|
|
/* Call the task. */
|
|
r = sendrec(driver_e, &m);
|
|
if(r == OK && m.REP_STATUS == ERESTART) r = EDEADSRCDST;
|
|
|
|
/* As block I/O never SUSPENDs, safe cleanup must be done whether
|
|
* the I/O succeeded or not. */
|
|
if (safe) safe_io_cleanup(gid, gids, vec_grants);
|
|
|
|
/* RECOVERY:
|
|
* - send back dead driver number
|
|
* - VFS unmaps it, waits for new driver
|
|
* - VFS sends the new driver endp for the FS proc and the request again
|
|
*/
|
|
if (r != OK) {
|
|
if (r == EDEADSRCDST) {
|
|
printf("ISOFS(%d) dead driver %d\n", SELF_E, driver_e);
|
|
driver_endpoints[(dev >> MAJOR) & BYTE].driver_e = NONE;
|
|
return(r);
|
|
}
|
|
else if (r == ELOCKED) {
|
|
return(r);
|
|
}
|
|
else
|
|
panic("call_task: can't send/receive: %d", r);
|
|
} else {
|
|
/* Did the process we did the sendrec() for get a result? */
|
|
if (m.REP_ENDPT != proc_e) {
|
|
printf("ISOFS (%d) strange device reply from %d, type = %d, proc = %d (not %d) (2) ignored\n", SELF_E, m.m_source, m.m_type, proc_e, m.REP_ENDPT);
|
|
r = EIO;
|
|
}
|
|
}
|
|
|
|
/* Task has completed. See if call completed. */
|
|
if (m.REP_STATUS == SUSPEND) {
|
|
panic("ISOFS block_dev_io: driver returned SUSPEND");
|
|
}
|
|
|
|
if(buf != buf_used && r == OK) {
|
|
memcpy(buf, buf_used, bytes * sizeof(iovec_t));
|
|
}
|
|
|
|
return(m.REP_STATUS);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* gen_opcl *
|
|
*===========================================================================*/
|
|
PRIVATE int gen_opcl(
|
|
endpoint_t driver_e,
|
|
int op, /* operation, DEV_OPEN or DEV_CLOSE */
|
|
dev_t dev, /* device to open or close */
|
|
int proc_e, /* 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.*/
|
|
message dev_mess;
|
|
|
|
dev_mess.m_type = op;
|
|
dev_mess.DEVICE = (dev >> MINOR) & BYTE;
|
|
dev_mess.IO_ENDPT = proc_e;
|
|
dev_mess.COUNT = flags;
|
|
|
|
/* Call the task. */
|
|
gen_io(driver_e, &dev_mess);
|
|
|
|
return(dev_mess.REP_STATUS);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* gen_io *
|
|
*===========================================================================*/
|
|
PRIVATE int gen_io(task_nr, mess_ptr)
|
|
endpoint_t 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_e;
|
|
|
|
proc_e = mess_ptr->IO_ENDPT;
|
|
|
|
r = sendrec(task_nr, mess_ptr);
|
|
if(r == OK && mess_ptr->REP_STATUS == ERESTART) r = EDEADSRCDST;
|
|
if (r != OK) {
|
|
if (r == EDEADSRCDST) {
|
|
printf("fs: dead driver %d\n", task_nr);
|
|
panic("should handle crashed drivers");
|
|
/* dmap_unmap_by_endpt(task_nr); */
|
|
return r;
|
|
}
|
|
if (r == ELOCKED) {
|
|
printf("fs: ELOCKED talking to %d\n", task_nr);
|
|
return r;
|
|
}
|
|
panic("call_task: can't send/receive: %d", r);
|
|
}
|
|
|
|
/* Did the process we did the sendrec() for get a result? */
|
|
if (mess_ptr->REP_ENDPT != proc_e) {
|
|
printf(
|
|
"fs: strange device reply from %d, type = %d, proc = %d (not %d) (2) ignored\n",
|
|
mess_ptr->m_source,
|
|
mess_ptr->m_type,
|
|
proc_e,
|
|
mess_ptr->REP_ENDPT);
|
|
return(EIO);
|
|
}
|
|
|
|
return(OK);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* dev_close *
|
|
*===========================================================================*/
|
|
PUBLIC void dev_close(endpoint_t driver_e, dev_t dev)
|
|
{
|
|
(void) gen_opcl(driver_e, DEV_CLOSE, dev, 0, 0);
|
|
}
|
|
|