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minix/servers/inet/sr.c
David van Moolenbroek c51cd5fe91 Server/driver protocols: no longer allow third-party copies. 
Before safecopies, the IO_ENDPT and DL_ENDPT message fields were needed
to know which actual process to copy data from/to, as that process may
not always be the caller. Now that we have full safecopy support, these
fields have become useless for that purpose: the owner of the grant is
*always* the caller. Allowing the caller to supply another endpoint is
in fact dangerous, because the callee may then end up using a grant
from a third party. One could call this a variant of the confused
deputy problem.

From now on, safecopy calls should always use the caller's endpoint as
grant owner. This fully obsoletes the DL_ENDPT field in the
inet/ethernet protocol. IO_ENDPT has other uses besides identifying the
grant owner though. This patch renames IO_ENDPT to USER_ENDPT, not only
because that is a more fitting name (it should never be used for I/O
after all), but also in order to intentionally break any old system
source code outside the base system. If this patch breaks your code,
fixing it is fairly simple:

- DL_ENDPT should be replaced with m_source;
- IO_ENDPT should be replaced with m_source when used for safecopies;
- IO_ENDPT should be replaced with USER_ENDPT for any other use, e.g.
  when setting REP_ENDPT, matching requests in CANCEL calls, getting
  DEV_SELECT flags, and retrieving of the real user process's endpoint
  in DEV_OPEN.

The changes in this patch are binary backward compatible.
2011-04-11 17:35:05 +00:00

1034 lines
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/* this file contains the interface of the network software with the file
* system.
*
* Copyright 1995 Philip Homburg
*
* The valid messages and their parameters are:
*
* Requests:
*
* m_type DEVICE USER_ENDPT COUNT
* --------------------------------------------------
* | DEV_OPEN | minor dev | proc nr | mode |
* |-------------+-----------+-----------+----------+
* | DEV_CLOSE | minor dev | proc nr | |
* |-------------+-----------+-----------+----------+
*
* m_type DEVICE USER_ENDPT COUNT IO_GRANT
* ---------------------------------------------------------------
* | DEV_READ_S | minor dev | proc nr | count | grant ID |
* |-------------+-----------+-----------+-----------+-----------|
* | DEV_WRITE_S | minor dev | proc nr | count | grant ID |
* |-------------+-----------+-----------+-----------+-----------|
* | DEV_IOCTL_S | minor dev | proc nr | command | grant ID |
* |-------------+-----------+-----------+-----------+-----------|
* | DEV_SELECT | minor dev | ops | | |
* |-------------+-----------+-----------+-----------+-----------|
*
* m_type
* --------------|
* | DEV_STATUS |
* |-------------|
*
* m_type DEVICE USER_ENDPT COUNT
* --------------------------------------------------|
* | CANCEL | minor dev | proc nr | mode |
* |-------------+-----------+-----------+-----------|
*
* Replies:
*
* m_type REP_ENDPT REP_STATUS REP_IO_GRANT
* -------------------------------------------------------|
* | TASK_REPLY | proc nr | status | grant ID |
* |---------------+-----------+-----------+--------------|
*
* m_type REP_ENDPT REP_STATUS REP_IO_GRANT
* ----------------+-----------+--------------------------|
* | DEV_REVIVE | proc nr | | grant ID |
* |---------------+-----------+-----------+--------------|
* | DEV_IO_READY | minor dev | sel ops | |
* |---------------+-----------+-----------+--------------|
* | DEV_NO_STATUS | | | |
* |---------------+-----------+-----------+--------------|
*/
#include "inet.h"
#include <sys/svrctl.h>
#include <minix/callnr.h>
#include "mq.h"
#include "qp.h"
#include "proto.h"
#include "generic/type.h"
#include "generic/assert.h"
#include "generic/buf.h"
#include "generic/event.h"
#include "generic/sr.h"
#include "sr_int.h"
THIS_FILE
PUBLIC sr_fd_t sr_fd_table[FD_NR];
PRIVATE mq_t *repl_queue, *repl_queue_tail;
PRIVATE struct vscp_vec s_cp_req[SCPVEC_NR];
FORWARD _PROTOTYPE ( int sr_open, (message *m) );
FORWARD _PROTOTYPE ( void sr_close, (message *m) );
FORWARD _PROTOTYPE ( int sr_rwio, (mq_t *m) );
FORWARD _PROTOTYPE ( int sr_restart_read, (sr_fd_t *fdp) );
FORWARD _PROTOTYPE ( int sr_restart_write, (sr_fd_t *fdp) );
FORWARD _PROTOTYPE ( int sr_restart_ioctl, (sr_fd_t *fdp) );
FORWARD _PROTOTYPE ( int sr_cancel, (message *m) );
FORWARD _PROTOTYPE ( int sr_select, (message *m) );
FORWARD _PROTOTYPE ( void sr_status, (message *m) );
FORWARD _PROTOTYPE ( void sr_reply_, (mq_t *m, int reply, int is_revive) );
FORWARD _PROTOTYPE ( sr_fd_t *sr_getchannel, (int minor));
FORWARD _PROTOTYPE ( acc_t *sr_get_userdata, (int fd, size_t offset,
size_t count, int for_ioctl) );
FORWARD _PROTOTYPE ( int sr_put_userdata, (int fd, size_t offset,
acc_t *data, int for_ioctl) );
FORWARD _PROTOTYPE (void sr_select_res, (int fd, unsigned ops) );
FORWARD _PROTOTYPE ( int sr_repl_queue, (int proc, int ref, int operation) );
FORWARD _PROTOTYPE ( int walk_queue, (sr_fd_t *sr_fd, mq_t **q_head_ptr,
mq_t **q_tail_ptr, int type, int proc_nr, int ref, int first_flag) );
FORWARD _PROTOTYPE ( void sr_event, (event_t *evp, ev_arg_t arg) );
FORWARD _PROTOTYPE ( int cp_u2b, (endpoint_t proc, cp_grant_id_t gid,
vir_bytes offset, acc_t **var_acc_ptr, int size) );
FORWARD _PROTOTYPE ( int cp_b2u, (acc_t *acc_ptr, endpoint_t proc,
cp_grant_id_t gid, vir_bytes offset) );
PUBLIC void sr_init()
{
int i;
for (i=0; i<FD_NR; i++)
{
sr_fd_table[i].srf_flags= SFF_FREE;
ev_init(&sr_fd_table[i].srf_ioctl_ev);
ev_init(&sr_fd_table[i].srf_read_ev);
ev_init(&sr_fd_table[i].srf_write_ev);
}
repl_queue= NULL;
}
PUBLIC void sr_rec(m)
mq_t *m;
{
int result;
int send_reply, free_mess;
if (repl_queue)
{
if (m->mq_mess.m_type == CANCEL)
{
result= sr_repl_queue(m->mq_mess.USER_ENDPT,
(int)m->mq_mess.IO_GRANT, 0);
if (result)
{
mq_free(m);
return; /* canceled request in queue */
}
}
#if 0
else
sr_repl_queue(ANY, 0, 0);
#endif
}
switch (m->mq_mess.m_type)
{
case DEV_OPEN:
result= sr_open(&m->mq_mess);
send_reply= 1;
free_mess= 1;
break;
case DEV_CLOSE:
sr_close(&m->mq_mess);
result= OK;
send_reply= 1;
free_mess= 1;
break;
case DEV_READ_S:
case DEV_WRITE_S:
case DEV_IOCTL_S:
result= sr_rwio(m);
assert(result == OK || result == SUSPEND);
send_reply= (result == SUSPEND);
free_mess= 0;
break;
case CANCEL:
result= sr_cancel(&m->mq_mess);
assert(result == OK || result == EINTR);
send_reply= (result == EINTR);
free_mess= 1;
m->mq_mess.m_type= 0;
break;
case DEV_SELECT:
result= sr_select(&m->mq_mess);
send_reply= 1;
free_mess= 1;
break;
case DEV_STATUS:
sr_status(&m->mq_mess);
result= OK; /* Satisfy lint. */
send_reply= 0;
free_mess= 1;
break;
default:
ip_panic(("unknown message, from %d, type %d",
m->mq_mess.m_source, m->mq_mess.m_type));
}
if (send_reply)
{
sr_reply_(m, result, FALSE /* !is_revive */);
}
if (free_mess)
mq_free(m);
}
PUBLIC void sr_add_minor(minor, port, openf, closef, readf, writef,
ioctlf, cancelf, selectf)
int minor;
int port;
sr_open_t openf;
sr_close_t closef;
sr_read_t readf;
sr_write_t writef;
sr_ioctl_t ioctlf;
sr_cancel_t cancelf;
sr_select_t selectf;
{
sr_fd_t *sr_fd;
assert (minor>=0 && minor<FD_NR);
sr_fd= &sr_fd_table[minor];
assert(!(sr_fd->srf_flags & SFF_INUSE));
sr_fd->srf_flags= SFF_INUSE | SFF_MINOR;
sr_fd->srf_port= port;
sr_fd->srf_open= openf;
sr_fd->srf_close= closef;
sr_fd->srf_write= writef;
sr_fd->srf_read= readf;
sr_fd->srf_ioctl= ioctlf;
sr_fd->srf_cancel= cancelf;
sr_fd->srf_select= selectf;
}
PRIVATE int sr_open(m)
message *m;
{
sr_fd_t *sr_fd;
int minor= m->DEVICE;
int i, fd;
if (minor<0 || minor>FD_NR)
{
DBLOCK(1, printf("replying EINVAL\n"));
return EINVAL;
}
if (!(sr_fd_table[minor].srf_flags & SFF_MINOR))
{
DBLOCK(1, printf("replying ENXIO\n"));
return ENXIO;
}
for (i=0; i<FD_NR && (sr_fd_table[i].srf_flags & SFF_INUSE); i++);
if (i>=FD_NR)
{
DBLOCK(1, printf("replying ENFILE\n"));
return ENFILE;
}
sr_fd= &sr_fd_table[i];
*sr_fd= sr_fd_table[minor];
sr_fd->srf_flags= SFF_INUSE;
fd= (*sr_fd->srf_open)(sr_fd->srf_port, i, sr_get_userdata,
sr_put_userdata, 0 /* no put_pkt */, sr_select_res);
if (fd<0)
{
sr_fd->srf_flags= SFF_FREE;
DBLOCK(1, printf("replying %d\n", fd));
return fd;
}
sr_fd->srf_fd= fd;
return i;
}
PRIVATE void sr_close(m)
message *m;
{
sr_fd_t *sr_fd;
sr_fd= sr_getchannel(m->DEVICE);
assert (sr_fd);
if (sr_fd->srf_flags & SFF_BUSY)
ip_panic(("close on busy channel"));
assert (!(sr_fd->srf_flags & SFF_MINOR));
(*sr_fd->srf_close)(sr_fd->srf_fd);
sr_fd->srf_flags= SFF_FREE;
}
PRIVATE int sr_rwio(m)
mq_t *m;
{
sr_fd_t *sr_fd;
mq_t **q_head_ptr, **q_tail_ptr;
int ip_flag, susp_flag, first_flag;
int r;
ioreq_t request;
size_t size;
sr_fd= sr_getchannel(m->mq_mess.DEVICE);
assert (sr_fd);
switch(m->mq_mess.m_type)
{
case DEV_READ_S:
q_head_ptr= &sr_fd->srf_read_q;
q_tail_ptr= &sr_fd->srf_read_q_tail;
ip_flag= SFF_READ_IP;
susp_flag= SFF_READ_SUSP;
first_flag= SFF_READ_FIRST;
break;
case DEV_WRITE_S:
q_head_ptr= &sr_fd->srf_write_q;
q_tail_ptr= &sr_fd->srf_write_q_tail;
ip_flag= SFF_WRITE_IP;
susp_flag= SFF_WRITE_SUSP;
first_flag= SFF_WRITE_FIRST;
break;
case DEV_IOCTL_S:
q_head_ptr= &sr_fd->srf_ioctl_q;
q_tail_ptr= &sr_fd->srf_ioctl_q_tail;
ip_flag= SFF_IOCTL_IP;
susp_flag= SFF_IOCTL_SUSP;
first_flag= SFF_IOCTL_FIRST;
break;
default:
ip_panic(("illegal case entry"));
}
if (sr_fd->srf_flags & ip_flag)
{
assert(sr_fd->srf_flags & susp_flag);
assert(*q_head_ptr);
(*q_tail_ptr)->mq_next= m;
*q_tail_ptr= m;
return SUSPEND;
}
assert(!*q_head_ptr);
*q_tail_ptr= *q_head_ptr= m;
sr_fd->srf_flags |= ip_flag;
assert(!(sr_fd->srf_flags & first_flag));
sr_fd->srf_flags |= first_flag;
switch(m->mq_mess.m_type)
{
case DEV_READ_S:
r= (*sr_fd->srf_read)(sr_fd->srf_fd,
m->mq_mess.COUNT);
break;
case DEV_WRITE_S:
r= (*sr_fd->srf_write)(sr_fd->srf_fd,
m->mq_mess.COUNT);
break;
case DEV_IOCTL_S:
request= m->mq_mess.REQUEST;
size= (request >> 16) & _IOCPARM_MASK;
if (size>MAX_IOCTL_S)
{
DBLOCK(1, printf("replying EINVAL\n"));
r= sr_put_userdata(sr_fd-sr_fd_table, EINVAL,
NULL, 1);
assert(r == OK);
assert(sr_fd->srf_flags & first_flag);
sr_fd->srf_flags &= ~first_flag;
return OK;
}
r= (*sr_fd->srf_ioctl)(sr_fd->srf_fd, request);
break;
default:
ip_panic(("illegal case entry"));
}
assert(sr_fd->srf_flags & first_flag);
sr_fd->srf_flags &= ~first_flag;
assert(r == OK || r == SUSPEND ||
(printf("r= %d\n", r), 0));
if (r == SUSPEND)
sr_fd->srf_flags |= susp_flag;
else
mq_free(m);
return r;
}
PRIVATE int sr_restart_read(sr_fd)
sr_fd_t *sr_fd;
{
mq_t *mp;
int r;
mp= sr_fd->srf_read_q;
assert(mp);
if (sr_fd->srf_flags & SFF_READ_IP)
{
assert(sr_fd->srf_flags & SFF_READ_SUSP);
return SUSPEND;
}
sr_fd->srf_flags |= SFF_READ_IP;
r= (*sr_fd->srf_read)(sr_fd->srf_fd,
mp->mq_mess.COUNT);
assert(r == OK || r == SUSPEND ||
(printf("r= %d\n", r), 0));
if (r == SUSPEND)
sr_fd->srf_flags |= SFF_READ_SUSP;
return r;
}
PRIVATE int sr_restart_write(sr_fd)
sr_fd_t *sr_fd;
{
mq_t *mp;
int r;
mp= sr_fd->srf_write_q;
assert(mp);
if (sr_fd->srf_flags & SFF_WRITE_IP)
{
assert(sr_fd->srf_flags & SFF_WRITE_SUSP);
return SUSPEND;
}
sr_fd->srf_flags |= SFF_WRITE_IP;
r= (*sr_fd->srf_write)(sr_fd->srf_fd,
mp->mq_mess.COUNT);
assert(r == OK || r == SUSPEND ||
(printf("r= %d\n", r), 0));
if (r == SUSPEND)
sr_fd->srf_flags |= SFF_WRITE_SUSP;
return r;
}
PRIVATE int sr_restart_ioctl(sr_fd)
sr_fd_t *sr_fd;
{
mq_t *mp;
int r;
mp= sr_fd->srf_ioctl_q;
assert(mp);
if (sr_fd->srf_flags & SFF_IOCTL_IP)
{
assert(sr_fd->srf_flags & SFF_IOCTL_SUSP);
return SUSPEND;
}
sr_fd->srf_flags |= SFF_IOCTL_IP;
r= (*sr_fd->srf_ioctl)(sr_fd->srf_fd,
mp->mq_mess.COUNT);
assert(r == OK || r == SUSPEND ||
(printf("r= %d\n", r), 0));
if (r == SUSPEND)
sr_fd->srf_flags |= SFF_IOCTL_SUSP;
return r;
}
PRIVATE int sr_cancel(m)
message *m;
{
sr_fd_t *sr_fd;
int result;
int proc_nr, ref;
result=EINTR;
proc_nr= m->USER_ENDPT;
ref= (int)m->IO_GRANT;
sr_fd= sr_getchannel(m->DEVICE);
assert (sr_fd);
result= walk_queue(sr_fd, &sr_fd->srf_ioctl_q,
&sr_fd->srf_ioctl_q_tail, SR_CANCEL_IOCTL,
proc_nr, ref, SFF_IOCTL_FIRST);
if (result != EAGAIN)
return result;
result= walk_queue(sr_fd, &sr_fd->srf_read_q,
&sr_fd->srf_read_q_tail, SR_CANCEL_READ,
proc_nr, ref, SFF_READ_FIRST);
if (result != EAGAIN)
return result;
result= walk_queue(sr_fd, &sr_fd->srf_write_q,
&sr_fd->srf_write_q_tail, SR_CANCEL_WRITE,
proc_nr, ref, SFF_WRITE_FIRST);
if (result != EAGAIN)
return result;
ip_panic((
"request not found: from %d, type %d, MINOR= %d, PROC= %d, REF= %d",
m->m_source, m->m_type, m->DEVICE,
m->USER_ENDPT, (int) m->IO_GRANT));
return result;
}
PRIVATE int sr_select(m)
message *m;
{
sr_fd_t *sr_fd;
int r;
unsigned m_ops, i_ops;
sr_fd= sr_getchannel(m->DEVICE);
assert (sr_fd);
sr_fd->srf_select_proc= m->m_source;
m_ops= m->USER_ENDPT;
i_ops= 0;
if (m_ops & SEL_RD) i_ops |= SR_SELECT_READ;
if (m_ops & SEL_WR) i_ops |= SR_SELECT_WRITE;
if (m_ops & SEL_ERR) i_ops |= SR_SELECT_EXCEPTION;
if (!(m_ops & SEL_NOTIFY)) i_ops |= SR_SELECT_POLL;
r= (*sr_fd->srf_select)(sr_fd->srf_fd, i_ops);
if (r < 0)
return r;
m_ops= 0;
if (r & SR_SELECT_READ) m_ops |= SEL_RD;
if (r & SR_SELECT_WRITE) m_ops |= SEL_WR;
if (r & SR_SELECT_EXCEPTION) m_ops |= SEL_ERR;
return m_ops;
}
PRIVATE void sr_status(m)
message *m;
{
int fd, result;
unsigned m_ops;
sr_fd_t *sr_fd;
mq_t *mq;
mq= repl_queue;
if (mq != NULL)
{
repl_queue= mq->mq_next;
mq->mq_mess.m_type= DEV_REVIVE;
result= send(mq->mq_mess.m_source, &mq->mq_mess);
if (result != OK)
ip_panic(("unable to send"));
mq_free(mq);
return;
}
for (fd=0, sr_fd= sr_fd_table; fd<FD_NR; fd++, sr_fd++)
{
if ((sr_fd->srf_flags &
(SFF_SELECT_R|SFF_SELECT_W|SFF_SELECT_X)) == 0)
{
/* Nothing to report */
continue;
}
if (sr_fd->srf_select_proc != m->m_source)
{
/* Wrong process */
continue;
}
m_ops= 0;
if (sr_fd->srf_flags & SFF_SELECT_R) m_ops |= SEL_RD;
if (sr_fd->srf_flags & SFF_SELECT_W) m_ops |= SEL_WR;
if (sr_fd->srf_flags & SFF_SELECT_X) m_ops |= SEL_ERR;
sr_fd->srf_flags &= ~(SFF_SELECT_R|SFF_SELECT_W|SFF_SELECT_X);
m->m_type= DEV_IO_READY;
m->DEV_MINOR= fd;
m->DEV_SEL_OPS= m_ops;
result= send(m->m_source, m);
if (result != OK)
ip_panic(("unable to send"));
return;
}
m->m_type= DEV_NO_STATUS;
result= send(m->m_source, m);
if (result != OK)
ip_panic(("unable to send"));
}
PRIVATE int walk_queue(sr_fd, q_head_ptr, q_tail_ptr, type, proc_nr, ref,
first_flag)
sr_fd_t *sr_fd;
mq_t **q_head_ptr;
mq_t **q_tail_ptr;
int type;
int proc_nr;
int ref;
int first_flag;
{
mq_t *q_ptr_prv, *q_ptr;
int result;
for(q_ptr_prv= NULL, q_ptr= *q_head_ptr; q_ptr;
q_ptr_prv= q_ptr, q_ptr= q_ptr->mq_next)
{
if (q_ptr->mq_mess.USER_ENDPT != proc_nr)
continue;
if ((int)q_ptr->mq_mess.IO_GRANT != ref)
continue;
if (!q_ptr_prv)
{
assert(!(sr_fd->srf_flags & first_flag));
sr_fd->srf_flags |= first_flag;
result= (*sr_fd->srf_cancel)(sr_fd->srf_fd, type);
assert(result == OK);
*q_head_ptr= q_ptr->mq_next;
mq_free(q_ptr);
assert(sr_fd->srf_flags & first_flag);
sr_fd->srf_flags &= ~first_flag;
return OK;
}
q_ptr_prv->mq_next= q_ptr->mq_next;
mq_free(q_ptr);
if (!q_ptr_prv->mq_next)
*q_tail_ptr= q_ptr_prv;
return EINTR;
}
return EAGAIN;
}
PRIVATE sr_fd_t *sr_getchannel(minor)
int minor;
{
sr_fd_t *loc_fd;
compare(minor, >=, 0);
compare(minor, <, FD_NR);
loc_fd= &sr_fd_table[minor];
assert (!(loc_fd->srf_flags & SFF_MINOR) &&
(loc_fd->srf_flags & SFF_INUSE));
return loc_fd;
}
PRIVATE void sr_reply_(mq, status, is_revive)
mq_t *mq;
int status;
int is_revive;
{
int result, proc, ref;
message reply, *mp;
proc= mq->mq_mess.USER_ENDPT;
ref= (int)mq->mq_mess.IO_GRANT;
if (is_revive)
mp= &mq->mq_mess;
else
mp= &reply;
mp->m_type= TASK_REPLY;
mp->REP_ENDPT= proc;
mp->REP_STATUS= status;
mp->REP_IO_GRANT= ref;
if (is_revive)
{
notify(mq->mq_mess.m_source);
result= ELOCKED;
}
else
{
result= send(mq->mq_mess.m_source, mp);
}
if (result == ELOCKED && is_revive)
{
mq->mq_next= NULL;
if (repl_queue)
repl_queue_tail->mq_next= mq;
else
repl_queue= mq;
repl_queue_tail= mq;
return;
}
if (result != OK)
ip_panic(("unable to send"));
if (is_revive)
mq_free(mq);
}
PRIVATE acc_t *sr_get_userdata (fd, offset, count, for_ioctl)
int fd;
size_t offset;
size_t count;
int for_ioctl;
{
sr_fd_t *loc_fd;
mq_t **head_ptr, *m, *mq;
int ip_flag, susp_flag, first_flag;
int result, suspended, is_revive;
acc_t *acc;
event_t *evp;
ev_arg_t arg;
loc_fd= &sr_fd_table[fd];
if (for_ioctl)
{
head_ptr= &loc_fd->srf_ioctl_q;
evp= &loc_fd->srf_ioctl_ev;
ip_flag= SFF_IOCTL_IP;
susp_flag= SFF_IOCTL_SUSP;
first_flag= SFF_IOCTL_FIRST;
}
else
{
head_ptr= &loc_fd->srf_write_q;
evp= &loc_fd->srf_write_ev;
ip_flag= SFF_WRITE_IP;
susp_flag= SFF_WRITE_SUSP;
first_flag= SFF_WRITE_FIRST;
}
assert (loc_fd->srf_flags & ip_flag);
if (!count)
{
m= *head_ptr;
mq= m->mq_next;
*head_ptr= mq;
result= (int)offset;
is_revive= !(loc_fd->srf_flags & first_flag);
sr_reply_(m, result, is_revive);
suspended= (loc_fd->srf_flags & susp_flag);
loc_fd->srf_flags &= ~(ip_flag|susp_flag);
if (suspended)
{
if (mq)
{
arg.ev_ptr= loc_fd;
ev_enqueue(evp, sr_event, arg);
}
}
return NULL;
}
result= cp_u2b ((*head_ptr)->mq_mess.m_source,
(int)(*head_ptr)->mq_mess.IO_GRANT, offset, &acc, count);
return result<0 ? NULL : acc;
}
PRIVATE int sr_put_userdata (fd, offset, data, for_ioctl)
int fd;
size_t offset;
acc_t *data;
int for_ioctl;
{
sr_fd_t *loc_fd;
mq_t **head_ptr, *m, *mq;
int ip_flag, susp_flag, first_flag;
int result, suspended, is_revive;
event_t *evp;
ev_arg_t arg;
loc_fd= &sr_fd_table[fd];
if (for_ioctl)
{
head_ptr= &loc_fd->srf_ioctl_q;
evp= &loc_fd->srf_ioctl_ev;
ip_flag= SFF_IOCTL_IP;
susp_flag= SFF_IOCTL_SUSP;
first_flag= SFF_IOCTL_FIRST;
}
else
{
head_ptr= &loc_fd->srf_read_q;
evp= &loc_fd->srf_read_ev;
ip_flag= SFF_READ_IP;
susp_flag= SFF_READ_SUSP;
first_flag= SFF_READ_FIRST;
}
assert (loc_fd->srf_flags & ip_flag);
if (!data)
{
m= *head_ptr;
mq= m->mq_next;
*head_ptr= mq;
result= (int)offset;
is_revive= !(loc_fd->srf_flags & first_flag);
sr_reply_(m, result, is_revive);
suspended= (loc_fd->srf_flags & susp_flag);
loc_fd->srf_flags &= ~(ip_flag|susp_flag);
if (suspended)
{
if (mq)
{
arg.ev_ptr= loc_fd;
ev_enqueue(evp, sr_event, arg);
}
}
return OK;
}
return cp_b2u (data, (*head_ptr)->mq_mess.m_source,
(int)(*head_ptr)->mq_mess.IO_GRANT, offset);
}
PRIVATE void sr_select_res(int fd, unsigned ops)
{
sr_fd_t *sr_fd;
sr_fd= &sr_fd_table[fd];
if (ops & SR_SELECT_READ) sr_fd->srf_flags |= SFF_SELECT_R;
if (ops & SR_SELECT_WRITE) sr_fd->srf_flags |= SFF_SELECT_W;
if (ops & SR_SELECT_EXCEPTION) sr_fd->srf_flags |= SFF_SELECT_X;
notify(sr_fd->srf_select_proc);
}
PRIVATE void sr_event(evp, arg)
event_t *evp;
ev_arg_t arg;
{
sr_fd_t *sr_fd;
int r;
sr_fd= arg.ev_ptr;
if (evp == &sr_fd->srf_write_ev)
{
while(sr_fd->srf_write_q)
{
r= sr_restart_write(sr_fd);
if (r == SUSPEND)
return;
}
return;
}
if (evp == &sr_fd->srf_read_ev)
{
while(sr_fd->srf_read_q)
{
r= sr_restart_read(sr_fd);
if (r == SUSPEND)
return;
}
return;
}
if (evp == &sr_fd->srf_ioctl_ev)
{
while(sr_fd->srf_ioctl_q)
{
r= sr_restart_ioctl(sr_fd);
if (r == SUSPEND)
return;
}
return;
}
ip_panic(("sr_event: unknown event\n"));
}
PRIVATE int cp_u2b(proc, gid, offset, var_acc_ptr, size)
endpoint_t proc;
cp_grant_id_t gid;
vir_bytes offset;
acc_t **var_acc_ptr;
int size;
{
acc_t *acc;
int i, r;
acc= bf_memreq(size);
*var_acc_ptr= acc;
i=0;
while (acc)
{
size= (vir_bytes)acc->acc_length;
s_cp_req[i].v_from= proc;
s_cp_req[i].v_to= SELF;
s_cp_req[i].v_gid= gid;
s_cp_req[i].v_offset= offset;
s_cp_req[i].v_addr= (vir_bytes) ptr2acc_data(acc);
s_cp_req[i].v_bytes= size;
offset += size;
acc= acc->acc_next;
i++;
if (acc == NULL && i == 1)
{
r= sys_safecopyfrom(s_cp_req[0].v_from,
s_cp_req[0].v_gid, s_cp_req[0].v_offset,
s_cp_req[0].v_addr, s_cp_req[0].v_bytes, D);
if (r <0)
{
printf("sys_safecopyfrom failed: %d\n", r);
bf_afree(*var_acc_ptr);
*var_acc_ptr= 0;
return r;
}
i= 0;
continue;
}
if (i == SCPVEC_NR || acc == NULL)
{
r= sys_vsafecopy(s_cp_req, i);
if (r <0)
{
printf("cp_u2b: sys_vsafecopy failed: %d\n",
r);
bf_afree(*var_acc_ptr);
*var_acc_ptr= 0;
return r;
}
i= 0;
}
}
return OK;
}
PRIVATE int cp_b2u(acc_ptr, proc, gid, offset)
acc_t *acc_ptr;
endpoint_t proc;
cp_grant_id_t gid;
vir_bytes offset;
{
acc_t *acc;
int i, r, size;
acc= acc_ptr;
i=0;
while (acc)
{
size= (vir_bytes)acc->acc_length;
if (size)
{
s_cp_req[i].v_from= SELF;
s_cp_req[i].v_to= proc;
s_cp_req[i].v_gid= gid;
s_cp_req[i].v_offset= offset;
s_cp_req[i].v_addr= (vir_bytes) ptr2acc_data(acc);
s_cp_req[i].v_bytes= size;
i++;
}
offset += size;
acc= acc->acc_next;
if (acc == NULL && i == 1)
{
r= sys_safecopyto(s_cp_req[0].v_to,
s_cp_req[0].v_gid, s_cp_req[0].v_offset,
s_cp_req[0].v_addr, s_cp_req[0].v_bytes, D);
if (r <0)
{
printf("sys_safecopyto failed: %d\n", r);
bf_afree(acc_ptr);
return r;
}
i= 0;
continue;
}
if (i == SCPVEC_NR || acc == NULL)
{
r= sys_vsafecopy(s_cp_req, i);
if (r <0)
{
printf("cp_b2u: sys_vsafecopy failed: %d\n",
r);
bf_afree(acc_ptr);
return r;
}
i= 0;
}
}
bf_afree(acc_ptr);
return OK;
}
PRIVATE int sr_repl_queue(proc, ref, operation)
int proc;
int ref;
int operation;
{
mq_t *m, *m_cancel, *m_tmp;
mq_t *new_queue;
int result;
m_cancel= NULL;
new_queue= NULL;
for (m= repl_queue; m;)
{
if (m->mq_mess.REP_ENDPT == proc &&
m->mq_mess.REP_IO_GRANT == ref)
{
assert(!m_cancel);
m_cancel= m;
m= m->mq_next;
continue;
}
m_tmp= m;
m= m->mq_next;
m_tmp->mq_next= new_queue;
new_queue= m_tmp;
}
repl_queue= new_queue;
if (m_cancel)
{
result= send(m_cancel->mq_mess.m_source, &m_cancel->mq_mess);
if (result != OK)
ip_panic(("unable to send: %d", result));
mq_free(m_cancel);
return 1;
}
return 0;
}
/*
* $PchId: sr.c,v 1.17 2005/06/28 14:26:16 philip Exp $
*/
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