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safe conversion

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This commit is contained in:
Ben Gras 2006-06-20 08:56:58 +00:00
parent 5350645c86
commit 9fa06d5e3f
1 changed files with 35 additions and 8 deletions
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43
drivers/rescue/rescue.c
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@ -24,7 +24,7 @@ FORWARD _PROTOTYPE( void m_init, (int argc, char **argv) );
FORWARD _PROTOTYPE( char *m_name, (void) );
FORWARD _PROTOTYPE( struct device *m_prepare, (int device) );
FORWARD _PROTOTYPE( int m_transfer, (int proc_nr, int opcode, off_t position,
iovec_t *iov, unsigned nr_req) );
iovec_t *iov, unsigned nr_req, int safe));
FORWARD _PROTOTYPE( int m_do_open, (struct driver *dp, message *m_ptr) );
FORWARD _PROTOTYPE( void m_geometry, (struct partition *entry) );
@ -84,17 +84,18 @@ int device;
/*===========================================================================*
* m_transfer *
*===========================================================================*/
PRIVATE int m_transfer(proc_nr, opcode, position, iov, nr_req)
PRIVATE int m_transfer(proc_nr, opcode, position, iov, nr_req, safe)
int proc_nr; /* process doing the request */
int opcode; /* DEV_GATHER or DEV_SCATTER */
off_t position; /* offset on device to read or write */
iovec_t *iov; /* pointer to read or write request vector */
unsigned nr_req; /* length of request vector */
int safe; /* safe copies? */
{
/* Read or write one the driver's minor devices. */
int seg;
unsigned count, left, chunk;
vir_bytes user_vir;
vir_bytes user_vir, vir_offset = 0;
struct device *dv;
unsigned long dv_size;
int s;
@ -111,21 +112,47 @@ unsigned nr_req; /* length of request vector */
user_vir = iov->iov_addr;
/* Virtual copying. For rescue device. */
if (position >= dv_size) return(OK); /* check for EOF */
if (position >= dv_size) {
return(OK); /* check for EOF */
}
if (position + count > dv_size) count = dv_size - position;
seg = m_seg[m_device];
if (opcode == DEV_GATHER) { /* copy actual data */
sys_vircopy(SELF,seg,position, proc_nr,D,user_vir, count);
int r;
if(safe) {
if((r=sys_safecopyto(proc_nr, user_vir, vir_offset,
position, count, seg)) != OK) {
printf("rescue: safecopy failed to user (proc %d, grant %d), error %d\n",
proc_nr, user_vir, r);
return EIO;
}
} else {
sys_vircopy(SELF,seg,position, proc_nr,D,user_vir, count);
}
} else {
if(safe) {
if(sys_safecopyfrom(proc_nr, user_vir, vir_offset,
position, count, seg) != OK) {
return EIO;
}
} else {
sys_vircopy(proc_nr,D,user_vir, SELF,seg,position, count);
}
}
/* Book the number of bytes transferred. */
if(safe) {
vir_offset += count;
} else {
iov->iov_addr += count;
}
if ((iov->iov_size -= count) == 0) {
iov++;
nr_req--;
vir_offset = 0;
}
position += count;
iov->iov_addr += count;
if ((iov->iov_size -= count) == 0) { iov++; nr_req--; }
}
return(OK);
}