1 files changed, 282 insertions, 0 deletions

diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c
new file mode 100644
index 000000000000..24119434dca9
--- /dev/null
+++ b/sys/dev/md/md.c
@@ -0,0 +1,282 @@
+/*
+ * ----------------------------------------------------------------------------
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
+ * ----------------------------------------------------------------------------
+ *
+ * $FreeBSD$
+ *
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sysctl.h>
+#include <sys/kernel.h>
+#include <sys/buf.h>
+#include <sys/malloc.h>
+#include <sys/conf.h>
+#include <sys/disk.h>
+#include <sys/devicestat.h>
+#include <sys/module.h>
+#include <machine/bus.h>
+#include <machine/clock.h>
+#include <machine/resource.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+#include <vm/vm_param.h>
+
+#include <sys/bus.h>
+#include <isa/isareg.h>
+#include <isa/isavar.h>
+
+MALLOC_DEFINE(M_MD, "MD disk", "Memory Disk");
+MALLOC_DEFINE(M_MDSECT, "MD sectors", "Memory Disk Sectors");
+
+static int md_debug = 0;
+SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, "");
+
+#define CDEV_MAJOR	95
+#define BDEV_MAJOR	22
+
+static d_strategy_t mdstrategy;
+static d_open_t mdopen;
+static d_ioctl_t mdioctl;
+
+static struct cdevsw md_cdevsw = {
+        /* open */      mdopen,
+        /* close */     nullclose,
+        /* read */      physread,
+        /* write */     physwrite,
+        /* ioctl */     mdioctl,
+        /* stop */      nostop,
+        /* reset */     noreset,
+        /* devtotty */  nodevtotty,
+        /* poll */      nopoll,
+        /* mmap */      nommap,
+        /* strategy */  mdstrategy,
+        /* name */      "md",
+        /* parms */     noparms,
+        /* maj */       CDEV_MAJOR,
+        /* dump */      nodump,
+        /* psize */     nopsize,
+        /* flags */     D_DISK | D_CANFREE,
+        /* maxio */     0,
+        /* bmaj */      BDEV_MAJOR
+};
+static struct cdevsw mddisk_cdevsw;
+
+struct md_s {
+	int unit;
+	struct devstat stats;
+	struct buf_queue_head buf_queue;
+	struct disk disk;
+	dev_t dev;
+	unsigned nsect;
+	unsigned nsecp;
+	u_char **secp;
+
+	int busy;
+};
+
+static int mdunits;
+
+static int
+mdopen(dev_t dev, int flag, int fmt, struct proc *p)
+{
+	struct md_s *sc;
+	struct disklabel *dl;
+
+	if (md_debug)
+		printf("mdopen(%s %x %x %p)\n",
+			devtoname(dev), flag, fmt, p);
+
+	sc = dev->si_drv1;
+
+	dl = &sc->disk.d_label;
+	bzero(dl, sizeof(*dl));
+	dl->d_secsize = DEV_BSIZE;
+	dl->d_nsectors = 1024;
+	dl->d_ntracks = 1;
+	dl->d_secpercyl = dl->d_nsectors + dl->d_ntracks;
+	dl->d_secperunit = sc->nsect;
+	dl->d_ncylinders = dl->d_secperunit / dl->d_secpercyl;
+	return (0);
+}
+
+static int
+mdioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
+{
+
+	if (md_debug)
+		printf("mdioctl(%s %lx %p %x %p)\n",
+			devtoname(dev), cmd, addr, flags, p);
+
+	return (ENOIOCTL);
+}
+
+static void
+mdstrategy(struct buf *bp)
+{
+	int s, i;
+	struct md_s *sc;
+	devstat_trans_flags dop;
+	u_char *secp, **secpp, *dst;
+	unsigned secno, nsec, secval, uc;
+
+	if (md_debug > 1)
+		printf("mdstrategy(%p) %s %lx, %d, %ld, %p)\n",
+		    bp, devtoname(bp->b_dev), bp->b_flags, bp->b_blkno, 
+		    bp->b_bcount / DEV_BSIZE, bp->b_data);
+
+	sc = bp->b_dev->si_drv1;
+
+	s = splbio();
+
+	bufqdisksort(&sc->buf_queue, bp);
+
+	if (sc->busy) {
+		splx(s);
+		return;
+	}
+
+	sc->busy++;
+	
+	while (1) {
+		bp = bufq_first(&sc->buf_queue);
+		if (bp)
+			bufq_remove(&sc->buf_queue, bp);
+		splx(s);
+		if (!bp)
+			break;
+
+		devstat_start_transaction(&sc->stats);
+
+		if (bp->b_flags & B_FREEBUF) 
+			dop = DEVSTAT_NO_DATA;
+		else if (bp->b_flags & B_READ)
+			dop = DEVSTAT_READ;
+		else
+			dop = DEVSTAT_WRITE;
+
+		nsec = bp->b_bcount / DEV_BSIZE;
+		secno = bp->b_pblkno;
+		dst = bp->b_data;
+		while (nsec--) {
+
+			if (secno < sc->nsecp) {
+				secpp = &sc->secp[secno];
+				if ((u_int)secpp > 255) {
+					secp = *secpp;
+					secval = 0;
+				} else {
+					secp = 0;
+					secval = (u_int) secpp;
+				}
+			} else {
+				secpp = 0;
+				secp = 0;
+				secval = 0;
+			}
+
+			if (bp->b_flags & B_FREEBUF) {
+				if (secpp) {
+					if (secp)
+						FREE(secp, M_MDSECT);
+					*secpp = 0;
+				}
+			} else if (bp->b_flags & B_READ) {
+				if (secp) {
+					bcopy(secp, dst, DEV_BSIZE);
+				} else if (secval) {
+					for (i = 0; i < DEV_BSIZE; i++)
+						dst[i] = secval;
+				} else {
+					bzero(dst, DEV_BSIZE);
+				}
+			} else {
+				uc = dst[0];
+				for (i = 1; i < DEV_BSIZE; i++) 
+					if (dst[i] != uc)
+						break;
+				if (i == DEV_BSIZE && !uc) {
+					if (secp)
+						FREE(secp, M_MDSECT);
+					if (secpp)
+						*secpp = (u_char *)uc;
+				} else {
+					if (!secpp) {
+						MALLOC(secpp, u_char **, (secno + nsec + 1) * sizeof(u_char *), M_MD, M_WAITOK);
+						bzero(secpp, (secno + nsec + 1) * sizeof(u_char *));
+						bcopy(sc->secp, secpp, sc->nsecp * sizeof(u_char *));
+						FREE(sc->secp, M_MD);
+						sc->secp = secpp;
+						sc->nsecp = secno + nsec + 1;
+						secpp = &sc->secp[secno];
+					}
+					if (i == DEV_BSIZE) {
+						if (secp)
+							FREE(secp, M_MDSECT);
+						*secpp = (u_char *)uc;
+					} else {
+						if (!secp) 
+							MALLOC(secp, u_char *, DEV_BSIZE, M_MDSECT, M_WAITOK);
+						bcopy(dst, secp, DEV_BSIZE);
+
+						*secpp = secp;
+					}
+				}
+			}
+			secno++;
+			dst += DEV_BSIZE;
+		}
+
+		bp->b_resid = 0;
+		biodone(bp);
+		devstat_end_transaction(&sc->stats, bp->b_bcount,
+		    DEVSTAT_TAG_NONE, dop);
+
+		s = splbio();
+	}
+	sc->busy = 0;
+	return;
+}
+
+static dev_t
+mdcreate(void)
+{
+	struct md_s *sc;
+
+	MALLOC(sc, struct md_s *,sizeof(*sc), M_MD, M_WAITOK);
+	bzero(sc, sizeof(*sc));
+	sc->unit = mdunits++;
+
+	bufq_init(&sc->buf_queue);
+
+	devstat_add_entry(&sc->stats, "md", sc->unit, DEV_BSIZE,
+		DEVSTAT_NO_ORDERED_TAGS, 
+		DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER, 0x190);
+
+	sc->dev = disk_create(sc->unit, &sc->disk, 0, 
+	    &md_cdevsw, &mddisk_cdevsw);
+
+	sc->dev->si_drv1 = sc;
+	sc->nsect = 10000 * 2;	/* for now */
+	MALLOC(sc->secp, u_char **, sizeof(u_char *), M_MD, M_WAITOK);
+	bzero(sc->secp, sizeof(u_char *));
+	sc->nsecp = 1;
+
+	return (0);
+}
+
+static void
+md_drvinit(void *unused)
+{
+
+	mdcreate();
+}
+
+SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR, md_drvinit,NULL)
+