145 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			145 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
 | |
| /* Sending requests to VFS and handling the replies.  */
 | |
| 
 | |
| #define _SYSTEM 1
 | |
| 
 | |
| #include <minix/callnr.h>
 | |
| #include <minix/com.h>
 | |
| #include <minix/config.h>
 | |
| #include <minix/const.h>
 | |
| #include <minix/ds.h>
 | |
| #include <minix/endpoint.h>
 | |
| #include <minix/minlib.h>
 | |
| #include <minix/type.h>
 | |
| #include <minix/ipc.h>
 | |
| #include <minix/sysutil.h>
 | |
| #include <minix/syslib.h>
 | |
| #include <minix/type.h>
 | |
| #include <minix/bitmap.h>
 | |
| #include <string.h>
 | |
| #include <errno.h>
 | |
| #include <env.h>
 | |
| #include <unistd.h>
 | |
| #include <assert.h>
 | |
| #include <sys/param.h>
 | |
| 
 | |
| #include "proto.h"
 | |
| #include "glo.h"
 | |
| #include "util.h"
 | |
| #include "region.h"
 | |
| #include "sanitycheck.h"
 | |
| 
 | |
| #define STATELEN 70
 | |
| 
 | |
| static struct vfs_request_node {
 | |
| 	message			reqmsg;
 | |
| 	char			reqstate[STATELEN];
 | |
| 	void			*opaque;
 | |
| 	endpoint_t		who;
 | |
| 	int			req_id;
 | |
| 	vfs_callback_t		callback;
 | |
| 	struct vfs_request_node	*next;
 | |
| } *first_queued, *active;
 | |
| 
 | |
| static void activate(void)
 | |
| {
 | |
| 	assert(!active);
 | |
| 	assert(first_queued);
 | |
| 
 | |
| 	active = first_queued;
 | |
| 	first_queued = first_queued->next;
 | |
| 
 | |
| 	if(asynsend3(VFS_PROC_NR, &active->reqmsg, AMF_NOREPLY) != OK)
 | |
| 		panic("VM: asynsend to VFS failed");
 | |
| }
 | |
| 
 | |
| #define ID_MAX LONG_MAX
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *                              vfs_request                                 *
 | |
|  *===========================================================================*/
 | |
| int vfs_request(int reqno, int fd, struct vmproc *vmp, u64_t offset, u32_t len,
 | |
| 	vfs_callback_t reply_callback, void *cbarg, void *state, int statelen)
 | |
| {
 | |
| /* Perform an asynchronous request to VFS.
 | |
|  * We send a message of type VFS_VMCALL to VFS. VFS will respond
 | |
|  * with message type VM_VFS_REPLY. We send the request asynchronously
 | |
|  * and then handle the reply as it if were a VM_VFS_REPLY request.
 | |
|  */
 | |
|  	message *m;
 | |
| 	static int reqid = 0;
 | |
| 	struct vfs_request_node *reqnode;
 | |
| 
 | |
| 	reqid++;
 | |
| 
 | |
| 	assert(statelen <= STATELEN);
 | |
| 
 | |
| 	if(!SLABALLOC(reqnode)) {
 | |
| 		printf("vfs_request: no memory for request node\n");
 | |
| 		return ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	m = &reqnode->reqmsg;
 | |
| 	memset(m, 0, sizeof(*m));
 | |
| 	m->m_type = VFS_VMCALL;
 | |
| 	m->VFS_VMCALL_REQ = reqno;
 | |
| 	m->VFS_VMCALL_FD = fd;
 | |
| 	m->VFS_VMCALL_REQID = reqid;
 | |
| 	m->VFS_VMCALL_ENDPOINT = vmp->vm_endpoint;
 | |
| 	m->VFS_VMCALL_OFFSET = offset;
 | |
| 	m->VFS_VMCALL_LENGTH = len;
 | |
| 
 | |
| 	reqnode->who = vmp->vm_endpoint;
 | |
| 	reqnode->req_id = reqid;
 | |
| 	reqnode->next = first_queued;
 | |
| 	reqnode->callback = reply_callback;
 | |
| 	reqnode->opaque = cbarg;
 | |
| 	if(state) memcpy(reqnode->reqstate, state, statelen);
 | |
| 	first_queued = reqnode;
 | |
| 
 | |
| 	/* Send the request message if none pending. */
 | |
| 	if(!active)
 | |
| 		activate();
 | |
| 
 | |
| 	return OK;
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *                              do_vfs_reply                                 *
 | |
|  *===========================================================================*/
 | |
| int do_vfs_reply(message *m)
 | |
| {
 | |
| /* VFS has handled a VM request and VFS has replied. It must be the
 | |
|  * active request.
 | |
|  */
 | |
|  	struct vfs_request_node *orignode = active;
 | |
|  	vfs_callback_t req_callback;
 | |
| 	void *cbarg;
 | |
| 	int n;
 | |
| 	struct vmproc *vmp;
 | |
| 
 | |
| 	assert(active);
 | |
| 	assert(active->req_id == m->VMV_REQID);
 | |
| 
 | |
| 	/* the endpoint may have exited */
 | |
| 	if(vm_isokendpt(m->VMV_ENDPOINT, &n) != OK)
 | |
| 		vmp = NULL;
 | |
| 	else	vmp = &vmproc[n];
 | |
| 
 | |
| 	req_callback = active->callback;
 | |
| 	cbarg = active->opaque;
 | |
| 	active = NULL;
 | |
| 
 | |
| 	/* Invoke requested reply-callback within VM. */
 | |
| 	if(req_callback) req_callback(vmp, m, cbarg, orignode->reqstate);
 | |
| 
 | |
| 	SLABFREE(orignode);
 | |
| 
 | |
| 	/* Send the next request message if any and not re-activated. */
 | |
| 	if(first_queued && !active)
 | |
| 		activate();
 | |
| 
 | |
| 	return SUSPEND;	/* don't reply to the reply */
 | |
| }
 | |
| 
 | 
