Exemplo n.º 1
0
int
ehci_send_bulk(struct usb_pipe *p, int dir, void *data, int datasize)
{
    if (! CONFIG_USB_EHCI)
        return -1;
    struct ehci_pipe *pipe = container_of(p, struct ehci_pipe, pipe);
    dprintf(7, "ehci_send_bulk qh=%p dir=%d data=%p size=%d\n"
            , &pipe->qh, dir, data, datasize);

    // Allocate 4 tds on stack (16byte aligned)
    u8 tdsbuf[sizeof(struct ehci_qtd) * STACKQTDS + EHCI_QTD_ALIGN - 1];
    struct ehci_qtd *tds = (void*)ALIGN((u32)tdsbuf, EHCI_QTD_ALIGN);
    memset(tds, 0, sizeof(*tds) * STACKQTDS);

    // Setup fields in qh
    u16 maxpacket = GET_FLATPTR(pipe->pipe.maxpacket);
    SET_FLATPTR(pipe->qh.info1
                , ((1 << QH_MULT_SHIFT)
                   | (maxpacket << QH_MAXPACKET_SHIFT)
                   | (GET_FLATPTR(pipe->pipe.speed) << QH_SPEED_SHIFT)
                   | (GET_FLATPTR(pipe->pipe.ep) << QH_EP_SHIFT)
                   | (GET_FLATPTR(pipe->pipe.devaddr) << QH_DEVADDR_SHIFT)));
    SET_FLATPTR(pipe->qh.info2
                , ((1 << QH_MULT_SHIFT)
                   | (GET_FLATPTR(pipe->pipe.tt_port) << QH_HUBPORT_SHIFT)
                   | (GET_FLATPTR(pipe->pipe.tt_devaddr) << QH_HUBADDR_SHIFT)));
    barrier();
    SET_FLATPTR(pipe->qh.qtd_next, (u32)MAKE_FLATPTR(GET_SEG(SS), tds));

    int tdpos = 0;
    while (datasize) {
        struct ehci_qtd *td = &tds[tdpos++ % STACKQTDS];
        int ret = ehci_wait_td(pipe, td, 5000);
        if (ret)
            return -1;

        struct ehci_qtd *nexttd_fl = MAKE_FLATPTR(GET_SEG(SS)
                                                 , &tds[tdpos % STACKQTDS]);

        int transfer = fillTDbuffer(td, maxpacket, data, datasize);
        td->qtd_next = (transfer==datasize ? EHCI_PTR_TERM : (u32)nexttd_fl);
        td->alt_next = EHCI_PTR_TERM;
        barrier();
        td->token = (ehci_explen(transfer) | QTD_STS_ACTIVE
                     | (dir ? QTD_PID_IN : QTD_PID_OUT) | ehci_maxerr(3));

        data += transfer;
        datasize -= transfer;
    }
    int i;
    for (i=0; i<STACKQTDS; i++) {
        struct ehci_qtd *td = &tds[tdpos++ % STACKQTDS];
        int ret = ehci_wait_td(pipe, td, 5000);
        if (ret)
            return -1;
    }

    return 0;
}
Exemplo n.º 2
0
// Low-level usb command transmit function.
int
usb_process_op(struct disk_op_s *op)
{
    if (!CONFIG_USB_MSC)
        return 0;

    dprintf(16, "usb_cmd_data id=%p write=%d count=%d buf=%p\n"
            , op->drive_fl, 0, op->count, op->buf_fl);
    struct usbdrive_s *udrive_gf = container_of(
        op->drive_fl, struct usbdrive_s, drive);

    // Setup command block wrapper.
    struct cbw_s cbw;
    memset(&cbw, 0, sizeof(cbw));
    int blocksize = scsi_fill_cmd(op, cbw.CBWCB, USB_CDB_SIZE);
    if (blocksize < 0)
        return default_process_op(op);
    u32 bytes = blocksize * op->count;
    cbw.dCBWSignature = CBW_SIGNATURE;
    cbw.dCBWTag = 999; // XXX
    cbw.dCBWDataTransferLength = bytes;
    cbw.bmCBWFlags = scsi_is_read(op) ? USB_DIR_IN : USB_DIR_OUT;
    cbw.bCBWLUN = GET_GLOBALFLAT(udrive_gf->lun);
    cbw.bCBWCBLength = USB_CDB_SIZE;

    // Transfer cbw to device.
    int ret = usb_msc_send(udrive_gf, USB_DIR_OUT
                           , MAKE_FLATPTR(GET_SEG(SS), &cbw), sizeof(cbw));
    if (ret)
        goto fail;

    // Transfer data to/from device.
    if (bytes) {
        ret = usb_msc_send(udrive_gf, cbw.bmCBWFlags, op->buf_fl, bytes);
        if (ret)
            goto fail;
    }

    // Transfer csw info.
    struct csw_s csw;
    ret = usb_msc_send(udrive_gf, USB_DIR_IN
                       , MAKE_FLATPTR(GET_SEG(SS), &csw), sizeof(csw));
    if (ret)
        goto fail;

    if (!csw.bCSWStatus)
        return DISK_RET_SUCCESS;
    if (csw.bCSWStatus == 2)
        goto fail;

    if (blocksize)
        op->count -= csw.dCSWDataResidue / blocksize;
    return DISK_RET_EBADTRACK;

fail:
    // XXX - reset connection
    dprintf(1, "USB transmission failed\n");
    return DISK_RET_EBADTRACK;
}
Exemplo n.º 3
0
static int
ramdisk_copy(struct disk_op_s *op, int iswrite)
{
    u32 offset = GET_GLOBAL(op->drive_g->cntl_id);
    offset += (u32)op->lba * DISK_SECTOR_SIZE;
    u64 opd = GDT_DATA | GDT_LIMIT(0xfffff) | GDT_BASE((u32)op->buf_fl);
    u64 ramd = GDT_DATA | GDT_LIMIT(0xfffff) | GDT_BASE(offset);

    u64 gdt[6];
    if (iswrite) {
        gdt[2] = opd;
        gdt[3] = ramd;
    } else {
        gdt[2] = ramd;
        gdt[3] = opd;
    }

    // Call int 1587 to copy data.
    struct bregs br;
    memset(&br, 0, sizeof(br));
    br.flags = F_CF|F_IF;
    br.ah = 0x87;
    br.es = GET_SEG(SS);
    br.si = (u32)gdt;
    br.cx = op->count * DISK_SECTOR_SIZE / 2;
    call16_int(0x15, &br);

    if (br.flags & F_CF)
        return DISK_RET_EBADTRACK;
    return DISK_RET_SUCCESS;
}
Exemplo n.º 4
0
int
ehci_poll_intr(struct usb_pipe *p, void *data)
{
    ASSERT16();
    if (! CONFIG_USB_EHCI)
        return -1;
    struct ehci_pipe *pipe = container_of(p, struct ehci_pipe, pipe);
    struct ehci_qtd *td = GET_LOWFLAT(pipe->next_td);
    u32 token = GET_LOWFLAT(td->token);
    if (token & QTD_STS_ACTIVE)
        // No intrs found.
        return -1;
    // XXX - check for errors.

    // Copy data.
    int maxpacket = GET_LOWFLAT(pipe->pipe.maxpacket);
    int pos = td - GET_LOWFLAT(pipe->tds);
    void *tddata = GET_LOWFLAT(pipe->data) + maxpacket * pos;
    memcpy_far(GET_SEG(SS), data, SEG_LOW, LOWFLAT2LOW(tddata), maxpacket);

    // Reenable this td.
    struct ehci_qtd *next = (void*)(GET_LOWFLAT(td->qtd_next) & ~EHCI_PTR_BITS);
    SET_LOWFLAT(pipe->next_td, next);
    SET_LOWFLAT(td->buf[0], (u32)tddata);
    barrier();
    SET_LOWFLAT(td->token, (ehci_explen(maxpacket) | QTD_STS_ACTIVE
                            | QTD_PID_IN | ehci_maxerr(3)));

    return 0;
}
Exemplo n.º 5
0
/*
 * Do a signal return; undo the signal stack.
 */
static int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
		   unsigned long *pax)
{
	void __user *buf;
	unsigned int tmpflags;
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	GET_SEG(gs);
	COPY_SEG(fs);
	COPY_SEG(es);
	COPY_SEG(ds);
	COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
	COPY(dx); COPY(cx); COPY(ip);
	COPY_SEG_STRICT(cs);
	COPY_SEG_STRICT(ss);

	err |= __get_user(tmpflags, &sc->flags);
	regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
	regs->orig_ax = -1;		/* disable syscall checks */

	err |= __get_user(buf, &sc->fpstate);
	err |= restore_i387_xstate(buf);

	err |= __get_user(*pax, &sc->ax);
	return err;
}
Exemplo n.º 6
0
void
hash_destroy (HTAB	*hashp)
{
    /* cannot destroy a shared memory hash table */
    Assert(! hashp->segbase);
    
    if (hashp != NULL) {
	register SEG_OFFSET 	segNum;
	SEGMENT		segp;
	int			nsegs = hashp->hctl->nsegs;
	int 		j;
	BUCKET_INDEX	*elp,p,q;
	ELEMENT		*curr;
	
	for (segNum =  0;  nsegs > 0; nsegs--, segNum++) {
	    
	    segp = GET_SEG(hashp,segNum);
	    for (j = 0, elp = segp; j < hashp->hctl->ssize; j++, elp++) {
		for ( p = *elp; p != INVALID_INDEX; p = q ){
		    curr = GET_BUCKET(hashp,p);
		    q = curr->next;
		    MEM_FREE((char *) curr);
		}
	    }
	    free((char *)segp);
	}
	(void) MEM_FREE( (char *) hashp->dir);
	(void) MEM_FREE( (char *) hashp->hctl);
	hash_stats("destroy",hashp);
	(void) MEM_FREE( (char *) hashp);
    }
}
Exemplo n.º 7
0
int
ehci_send_bulk(struct usb_pipe *p, int dir, void *data, int datasize)
{
    if (! CONFIG_USB_EHCI)
        return -1;
    struct ehci_pipe *pipe = container_of(p, struct ehci_pipe, pipe);
    dprintf(7, "ehci_send_bulk qh=%p dir=%d data=%p size=%d\n"
            , &pipe->qh, dir, data, datasize);

    // Allocate 4 tds on stack (with required alignment)
    u8 tdsbuf[sizeof(struct ehci_qtd) * STACKQTDS + EHCI_QTD_ALIGN - 1];
    struct ehci_qtd *tds = (void*)ALIGN((u32)tdsbuf, EHCI_QTD_ALIGN);
    memset(tds, 0, sizeof(*tds) * STACKQTDS);
    barrier();
    SET_LOWFLAT(pipe->qh.qtd_next, (u32)MAKE_FLATPTR(GET_SEG(SS), tds));

    u16 maxpacket = GET_LOWFLAT(pipe->pipe.maxpacket);
    int tdpos = 0;
    while (datasize) {
        struct ehci_qtd *td = &tds[tdpos++ % STACKQTDS];
        int ret = ehci_wait_td(pipe, td, 5000);
        if (ret)
            return -1;

        struct ehci_qtd *nexttd_fl = MAKE_FLATPTR(GET_SEG(SS)
                                                 , &tds[tdpos % STACKQTDS]);

        int transfer = fillTDbuffer(td, maxpacket, data, datasize);
        td->qtd_next = (transfer==datasize ? EHCI_PTR_TERM : (u32)nexttd_fl);
        td->alt_next = EHCI_PTR_TERM;
        barrier();
        td->token = (ehci_explen(transfer) | QTD_STS_ACTIVE
                     | (dir ? QTD_PID_IN : QTD_PID_OUT) | ehci_maxerr(3));

        data += transfer;
        datasize -= transfer;
    }
    int i;
    for (i=0; i<STACKQTDS; i++) {
        struct ehci_qtd *td = &tds[tdpos++ % STACKQTDS];
        int ret = ehci_wait_td(pipe, td, 5000);
        if (ret)
            return -1;
    }

    return 0;
}
Exemplo n.º 8
0
Arquivo: signal.c Projeto: aldld/linux
int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
	unsigned long buf_val;
	void __user *buf;
	unsigned int tmpflags;
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current->restart_block.fn = do_no_restart_syscall;

	get_user_try {

#ifdef CONFIG_X86_32
		set_user_gs(regs, GET_SEG(gs));
		COPY_SEG(fs);
		COPY_SEG(es);
		COPY_SEG(ds);
#endif /* CONFIG_X86_32 */

		COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
		COPY(dx); COPY(cx); COPY(ip); COPY(ax);

#ifdef CONFIG_X86_64
		COPY(r8);
		COPY(r9);
		COPY(r10);
		COPY(r11);
		COPY(r12);
		COPY(r13);
		COPY(r14);
		COPY(r15);
#endif /* CONFIG_X86_64 */

#ifdef CONFIG_X86_32
		COPY_SEG_CPL3(cs);
		COPY_SEG_CPL3(ss);
#else /* !CONFIG_X86_32 */
		/* Kernel saves and restores only the CS segment register on signals,
		 * which is the bare minimum needed to allow mixed 32/64-bit code.
		 * App's signal handler can save/restore other segments if needed. */
		COPY_SEG_CPL3(cs);
#endif /* CONFIG_X86_32 */

		get_user_ex(tmpflags, &sc->flags);
		regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
		regs->orig_ax = -1;		/* disable syscall checks */

		get_user_ex(buf_val, &sc->fpstate);
		buf = (void __user *)buf_val;
	} get_user_catch(err);

	err |= fpu__restore_sig(buf, config_enabled(CONFIG_X86_32));

	force_iret();

	return err;
}
Exemplo n.º 9
0
int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
		       unsigned long *pax)
{
	void __user *buf;
	unsigned int tmpflags;
	unsigned int err = 0;

	/*                                                              */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	get_user_try {

#ifdef CONFIG_X86_32
		set_user_gs(regs, GET_SEG(gs));
		COPY_SEG(fs);
		COPY_SEG(es);
		COPY_SEG(ds);
#endif /*               */

		COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
		COPY(dx); COPY(cx); COPY(ip);

#ifdef CONFIG_X86_64
		COPY(r8);
		COPY(r9);
		COPY(r10);
		COPY(r11);
		COPY(r12);
		COPY(r13);
		COPY(r14);
		COPY(r15);
#endif /*               */

#ifdef CONFIG_X86_32
		COPY_SEG_CPL3(cs);
		COPY_SEG_CPL3(ss);
#else /*                */
		/*                                                                   
                                                                    
                                                                     */
		COPY_SEG_CPL3(cs);
#endif /*               */

		get_user_ex(tmpflags, &sc->flags);
		regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
		regs->orig_ax = -1;		/*                        */

		get_user_ex(buf, &sc->fpstate);
		err |= restore_i387_xstate(buf);

		get_user_ex(*pax, &sc->ax);
	} get_user_catch(err);

	return err;
}
Exemplo n.º 10
0
// Execute a "disk_op_s" request (using the extra 16bit stack).
static int
send_disk_op(struct disk_op_s *op)
{
    ASSERT16();
    if (! CONFIG_DRIVES)
        return -1;
    if (!CONFIG_ENTRY_EXTRASTACK)
        // Jump on to extra stack
        return stack_hop(__send_disk_op, op, GET_SEG(SS));
    return process_op(op);
}
Exemplo n.º 11
0
// Execute a "disk_op_s" request after jumping to the extra stack.
static int
__send_disk_op(struct disk_op_s *op_far, u16 op_seg)
{
    struct disk_op_s dop;
    memcpy_far(GET_SEG(SS), &dop, op_seg, op_far, sizeof(dop));

    int status = process_op(&dop);

    // Update count with total sectors transferred.
    SET_FARVAR(op_seg, op_far->count, dop.count);

    return status;
}
Exemplo n.º 12
0
int
usb_poll_intr(struct usb_pipe *pipe_fl, void *data)
{
    ASSERT16();
    switch (GET_LOWFLAT(pipe_fl->type)) {
    default:
    case USB_TYPE_UHCI:
        return uhci_poll_intr(pipe_fl, data);
    case USB_TYPE_OHCI:
        return ohci_poll_intr(pipe_fl, data);
    case USB_TYPE_EHCI:
        return ehci_poll_intr(pipe_fl, data);
    case USB_TYPE_XHCI: ;
        return call32_params(xhci_poll_intr, pipe_fl
                             , MAKE_FLATPTR(GET_SEG(SS), data), 0, -1);
    }
}
Exemplo n.º 13
0
int
usb_poll_intr(struct usb_pipe *pipe_fl, void *data)
{
    ASSERT16();
    switch (GET_LOWFLAT(pipe_fl->type)) {
    default:
    case USB_TYPE_UHCI:
        return uhci_poll_intr(pipe_fl, data);
    case USB_TYPE_OHCI:
        return ohci_poll_intr(pipe_fl, data);
    case USB_TYPE_EHCI:
        return ehci_poll_intr(pipe_fl, data);
    case USB_TYPE_XHCI: ;
        extern void _cfunc32flat_xhci_poll_intr(void);
        return call32_params(_cfunc32flat_xhci_poll_intr, (u32)pipe_fl
                             , (u32)MAKE_FLATPTR(GET_SEG(SS), (u32)data), 0, -1);
    }
}
Exemplo n.º 14
0
int
ohci_poll_intr(struct usb_pipe *pipe, void *data)
{
    ASSERT16();
    if (! CONFIG_USB_OHCI)
        return -1;

    struct ohci_pipe *p = container_of(pipe, struct ohci_pipe, pipe);
    struct ohci_td *tds = GET_FLATPTR(p->tds);
    struct ohci_td *head = (void*)GET_FLATPTR(p->ed.hwHeadP);
    struct ohci_td *tail = (void*)GET_FLATPTR(p->ed.hwTailP);
    int count = GET_FLATPTR(p->count);
    int pos = (tail - tds + 1) % count;
    struct ohci_td *next = &tds[pos];
    if (head == next)
        // No intrs found.
        return -1;
    // XXX - check for errors.

    // Copy data.
    u32 endp = GET_FLATPTR(p->pipe.endp);
    int maxpacket = endp2maxsize(endp);
    void *pipedata = GET_FLATPTR(p->data);
    void *intrdata = pipedata + maxpacket * pos;
    memcpy_far(GET_SEG(SS), data
               , FLATPTR_TO_SEG(intrdata), (void*)FLATPTR_TO_OFFSET(intrdata)
               , maxpacket);

    // Reenable this td.
    SET_FLATPTR(tail->hwINFO, TD_DP_IN | TD_T_TOGGLE | TD_CC);
    intrdata = pipedata + maxpacket * (tail-tds);
    SET_FLATPTR(tail->hwCBP, (u32)intrdata);
    SET_FLATPTR(tail->hwNextTD, (u32)next);
    SET_FLATPTR(tail->hwBE, (u32)intrdata + maxpacket - 1);

    SET_FLATPTR(p->ed.hwTailP, (u32)next);

    return 0;
}
Exemplo n.º 15
0
static int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax)
{
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

#define COPY(x)		err |= __get_user(regs->x, &sc->x)

#define COPY_SEG(seg)							\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  regs->x##seg = tmp; }

#define COPY_SEG_STRICT(seg)						\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  regs->x##seg = tmp|3; }

#define GET_SEG(seg)							\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  loadsegment(seg,tmp); }

#define	FIX_EFLAGS	(X86_EFLAGS_AC | X86_EFLAGS_RF |		 \
			 X86_EFLAGS_OF | X86_EFLAGS_DF |		 \
			 X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \
			 X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF)

	GET_SEG(gs);
	COPY_SEG(fs);
	COPY_SEG(es);
	COPY_SEG(ds);
	COPY(edi);
	COPY(esi);
	COPY(ebp);
	COPY(esp);
	COPY(ebx);
	COPY(edx);
	COPY(ecx);
	COPY(eip);
	COPY_SEG_STRICT(cs);
	COPY_SEG_STRICT(ss);
	
	{
		unsigned int tmpflags;
		err |= __get_user(tmpflags, &sc->eflags);
		regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
		regs->orig_eax = -1;		/* disable syscall checks */
	}

	{
		struct _fpstate __user * buf;
		err |= __get_user(buf, &sc->fpstate);
		if (buf) {
			if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
				goto badframe;
			err |= restore_i387(buf);
		} else {
			struct task_struct *me = current;
			if (used_math()) {
				clear_fpu(me);
				clear_used_math();
			}
		}
	}

	err |= __get_user(*peax, &sc->eax);
	return err;

badframe:
	return 1;
}
Exemplo n.º 16
0
/********************************* UTILITIES ************************/
static int
expand_table(HTAB *hashp)
{
    HHDR	*hctl;
    SEGMENT	old_seg,new_seg;
    long	old_bucket, new_bucket;
    long	new_segnum, new_segndx;
    long	old_segnum, old_segndx;
    ELEMENT	*chain;
    BUCKET_INDEX *old,*newbi;
    register BUCKET_INDEX chainIndex,nextIndex;
    
#ifdef HASH_STATISTICS
    hash_expansions++;
#endif
    
    hctl = hashp->hctl;
    new_bucket = ++hctl->max_bucket;
    old_bucket = (hctl->max_bucket & hctl->low_mask);
    
    new_segnum = new_bucket >> hctl->sshift;
    new_segndx = MOD ( new_bucket, hctl->ssize );
    
    if ( new_segnum >= hctl->nsegs ) {
	
	/* Allocate new segment if necessary */
	if (new_segnum >= hctl->dsize) {
	    dir_realloc(hashp);
	}
	if (! (hashp->dir[new_segnum] = seg_alloc(hashp))) {
	    return (0);
	}
	hctl->nsegs++;
    }
    
    
    if ( new_bucket > hctl->high_mask ) {
	/* Starting a new doubling */
	hctl->low_mask = hctl->high_mask;
	hctl->high_mask = new_bucket | hctl->low_mask;
    }
    
    /*
     * Relocate records to the new bucket
     */
    old_segnum = old_bucket >> hctl->sshift;
    old_segndx = MOD(old_bucket, hctl->ssize);
    
    old_seg = GET_SEG(hashp,old_segnum);
    new_seg = GET_SEG(hashp,new_segnum);
    
    old = &old_seg[old_segndx];
    newbi = &new_seg[new_segndx];
    for (chainIndex = *old; 
	 chainIndex != INVALID_INDEX;
	 chainIndex = nextIndex){
	
	chain = GET_BUCKET(hashp,chainIndex);
	nextIndex = chain->next;
	if ( call_hash(hashp,
		       (char *)&(chain->key),
		       hctl->keysize) == old_bucket ) {
	    *old = chainIndex;
	    old = &chain->next;
	} else {
	    *newbi = chainIndex;
	    newbi = &chain->next;
	}
	chain->next = INVALID_INDEX;
    }
    return (1);
}
Exemplo n.º 17
0
/*
 * hash_seq -- sequentially search through hash table and return
 *             all the elements one by one, return NULL on error and
 *	       return TRUE in the end.
 *
 */
long *
hash_seq(HTAB *hashp)
{
    static uint32 curBucket = 0;
    static BUCKET_INDEX curIndex;
    ELEMENT *curElem;
    long segment_num;
    long segment_ndx;
    SEGMENT segp;
    HHDR *hctl;
    
    if (hashp == NULL)
	{
	    /*
	     * reset static state
	     */
	    curBucket = 0;
	    curIndex = INVALID_INDEX;
	    return((long *) NULL);
	}
    
    hctl = hashp->hctl;
    while (curBucket <= hctl->max_bucket) {
	if (curIndex != INVALID_INDEX) {
	    curElem = GET_BUCKET(hashp, curIndex);
	    curIndex = curElem->next;
	    if (curIndex == INVALID_INDEX)	/* end of this bucket */
		++curBucket;
	    return(&(curElem->key));
	}
	
	/*
	 * initialize the search within this bucket.
	 */
	segment_num = curBucket >> hctl->sshift;
	segment_ndx = curBucket & ( hctl->ssize - 1 );
	
	/*
	 * first find the right segment in the table directory.
	 */
	segp = GET_SEG(hashp, segment_num);
	if (segp == NULL)
	    /* this is probably an error */
	    return((long *) NULL);
	
	/*
	 * now find the right index into the segment for the first
	 * item in this bucket's chain.  if the bucket is not empty
	 * (its entry in the dir is valid), we know this must
	 * correspond to a valid element and not a freed element
	 * because it came out of the directory of valid stuff.  if
	 * there are elements in the bucket chains that point to the
	 * freelist we're in big trouble.
	 */
	curIndex = segp[segment_ndx];
	
	if (curIndex == INVALID_INDEX)		/* empty bucket */
	    ++curBucket;
    }
    
    return((long *) TRUE);			/* out of buckets */
}
Exemplo n.º 18
0
/*
 * hash_search -- look up key in table and perform action
 *
 * action is one of HASH_FIND/HASH_ENTER/HASH_REMOVE
 *
 * RETURNS: NULL if table is corrupted, a pointer to the element
 * 	found/removed/entered if applicable, TRUE otherwise.
 *	foundPtr is TRUE if we found an element in the table 
 *	(FALSE if we entered one).
 */
long *
hash_search(HTAB *hashp,
	    char *keyPtr, 
	    HASHACTION action,	/*
				 * HASH_FIND / HASH_ENTER / HASH_REMOVE
				 * HASH_FIND_SAVE / HASH_REMOVE_SAVED
				 */
	    bool *foundPtr)
{
    uint32 bucket;
    long segment_num;
    long segment_ndx;
    SEGMENT segp;
    register ELEMENT *curr;
    HHDR	*hctl;
    BUCKET_INDEX	currIndex;
    BUCKET_INDEX	*prevIndexPtr;
    char *		destAddr;
    static struct State {
	ELEMENT      *currElem;
	BUCKET_INDEX currIndex;
	BUCKET_INDEX *prevIndex;
    } saveState;
    
    Assert((hashp && keyPtr));
    Assert((action == HASH_FIND) || (action == HASH_REMOVE) || (action == HASH_ENTER) || (action == HASH_FIND_SAVE) || (action == HASH_REMOVE_SAVED));
    
    hctl = hashp->hctl;
    
# if HASH_STATISTICS
    hash_accesses++;
    hashp->hctl->accesses++;
# endif
    if (action == HASH_REMOVE_SAVED)
	{
	    curr = saveState.currElem;
	    currIndex = saveState.currIndex;
	    prevIndexPtr = saveState.prevIndex;
	    /*
	     * Try to catch subsequent errors
	     */
	    Assert(saveState.currElem && !(saveState.currElem = 0));
	}
    else
	{
	    bucket = call_hash(hashp, keyPtr, hctl->keysize);
	    segment_num = bucket >> hctl->sshift;
	    segment_ndx = bucket & ( hctl->ssize - 1 );
	    
	    segp = GET_SEG(hashp,segment_num);
	    
	    Assert(segp);
	    
	    prevIndexPtr = &segp[segment_ndx];
	    currIndex = *prevIndexPtr;
	    /*
	     * Follow collision chain
	     */
	    for (curr = NULL;currIndex != INVALID_INDEX;) {
		/* coerce bucket index into a pointer */
		curr = GET_BUCKET(hashp,currIndex);
		
		if (! memcmp((char *)&(curr->key), keyPtr, hctl->keysize)) {
		    break;
		} 
		prevIndexPtr = &(curr->next);
		currIndex = *prevIndexPtr;
# if HASH_STATISTICS
		hash_collisions++;
		hashp->hctl->collisions++;
# endif
	    }
	}
    
    /*
     *  if we found an entry or if we weren't trying
     * to insert, we're done now.
     */
    *foundPtr = (bool) (currIndex != INVALID_INDEX);
    switch (action) {
    case HASH_ENTER:
	if (currIndex != INVALID_INDEX)
	    return(&(curr->key));
	break;
    case HASH_REMOVE:
    case HASH_REMOVE_SAVED:
	if (currIndex != INVALID_INDEX) {
	    Assert(hctl->nkeys > 0);
	    hctl->nkeys--;
	    
	    /* add the bucket to the freelist for this table.  */
	    *prevIndexPtr = curr->next;
	    curr->next = hctl->freeBucketIndex;
	    hctl->freeBucketIndex = currIndex;
	    
	    /* better hope the caller is synchronizing access to
	     * this element, because someone else is going to reuse
	     * it the next time something is added to the table
	     */
	    return (&(curr->key));
	}
	return((long *) TRUE);
    case HASH_FIND:
	if (currIndex != INVALID_INDEX)
	    return(&(curr->key));
	return((long *)TRUE);
    case HASH_FIND_SAVE:
	if (currIndex != INVALID_INDEX)
	    {
		saveState.currElem = curr;
		saveState.prevIndex = prevIndexPtr;
		saveState.currIndex = currIndex;
		return(&(curr->key));
	    }
	return((long *)TRUE);
    default:
	/* can't get here */
	return (NULL);
    }
    
    /* 
      If we got here, then we didn't find the element and
      we have to insert it into the hash table
      */
    Assert(currIndex == INVALID_INDEX);
    
    /* get the next free bucket */
    currIndex = hctl->freeBucketIndex;
    if (currIndex == INVALID_INDEX) {
	
	/* no free elements.  allocate another chunk of buckets */
	if (! bucket_alloc(hashp)) {
	    return(NULL);
	}
	currIndex = hctl->freeBucketIndex;
    }
    Assert(currIndex != INVALID_INDEX);
    
    curr = GET_BUCKET(hashp,currIndex);
    hctl->freeBucketIndex = curr->next;
    
    /* link into chain */
    *prevIndexPtr = currIndex;	
    
    /* copy key and data */
    destAddr = (char *) &(curr->key);
    memmove(destAddr,keyPtr,hctl->keysize);
    curr->next = INVALID_INDEX;
    
    /* let the caller initialize the data field after 
     * hash_search returns.
     */
    /*	memmove(destAddr,keyPtr,hctl->keysize+hctl->datasize);*/
    
    /*
     * Check if it is time to split the segment
     */
    if (++hctl->nkeys / (hctl->max_bucket+1) > hctl->ffactor) {
	/*
	  fprintf(stderr,"expanding on '%s'\n",keyPtr);
	  hash_stats("expanded table",hashp);
	  */
	if (! expand_table(hashp))
	    return(NULL);
    }
    return (&(curr->key));
}