Kill the cdevsw->d_maxio field.

d_maxio is replaced by the dev->si_iosize_max field which the driver
should be set in all calls to cdevsw->d_open if it has a better
idea than the system wide default.

The field is a generic dev_t field (ie: not disk specific) so that
tapes and other devices can use physio as well.

5 files changed, 26 insertions, 29 deletions

diff --git a/sys/fs/specfs/spec_vnops.c b/sys/fs/specfs/spec_vnops.c
index 0f4a334..e8a2163 100644
--- a/sys/fs/specfs/spec_vnops.c
+++ b/sys/fs/specfs/spec_vnops.c
@@ -167,6 +167,10 @@ spec_open(ap)
 	if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
 		return (ENXIO);
 
+	/* Make this field valid before any I/O in ->d_open */
+	if (!dev->si_iosize_max)
+		dev->si_iosize_max = DFLTPHYS;
+
 	switch (vp->v_type) {
 	case VCHR:
 		dsw = devsw(dev);
@@ -233,15 +237,13 @@ spec_open(ap)
 	if (vn_isdisk(vp)) {
 		if (!dev->si_bsize_phys)
 			dev->si_bsize_phys = DEV_BSIZE;
-		maxio = dev->si_iosize_max;
-		if (!maxio)
-			maxio = devsw(dev)->d_maxio;	/* XXX */
-		if (!maxio)
-			maxio = DFLTPHYS;
-		if (maxio > MAXPHYS)
-			maxio = MAXPHYS;
-		vp->v_maxio = maxio;
 	}
+	maxio = dev->si_iosize_max;
+	if (!maxio)
+		maxio = DFLTPHYS;
+	if (maxio > MAXPHYS)
+		maxio = MAXPHYS;
+	vp->v_maxio = maxio;
 
 	return (error);
 }
diff --git a/sys/kern/kern_physio.c b/sys/kern/kern_physio.c
index cc436bf..01bc7f3 100644
--- a/sys/kern/kern_physio.c
+++ b/sys/kern/kern_physio.c
@@ -172,14 +172,9 @@ u_int
 minphys(bp)
 	struct buf *bp;
 {
-	u_int maxphys = DFLTPHYS;
-	struct cdevsw *bdsw;
+	u_int maxphys;
 
-	bdsw = devsw(bp->b_dev);
-
-	if (bdsw && bdsw->d_maxio) {
-		maxphys = bdsw->d_maxio;
-	}
+	maxphys = bp->b_dev->si_iosize_max;
 	if (bp->b_kvasize && (bp->b_kvasize < maxphys))
 		maxphys = bp->b_kvasize;
 
diff --git a/sys/miscfs/specfs/spec_vnops.c b/sys/miscfs/specfs/spec_vnops.c
index 0f4a334..e8a2163 100644
--- a/sys/miscfs/specfs/spec_vnops.c
+++ b/sys/miscfs/specfs/spec_vnops.c
@@ -167,6 +167,10 @@ spec_open(ap)
 	if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
 		return (ENXIO);
 
+	/* Make this field valid before any I/O in ->d_open */
+	if (!dev->si_iosize_max)
+		dev->si_iosize_max = DFLTPHYS;
+
 	switch (vp->v_type) {
 	case VCHR:
 		dsw = devsw(dev);
@@ -233,15 +237,13 @@ spec_open(ap)
 	if (vn_isdisk(vp)) {
 		if (!dev->si_bsize_phys)
 			dev->si_bsize_phys = DEV_BSIZE;
-		maxio = dev->si_iosize_max;
-		if (!maxio)
-			maxio = devsw(dev)->d_maxio;	/* XXX */
-		if (!maxio)
-			maxio = DFLTPHYS;
-		if (maxio > MAXPHYS)
-			maxio = MAXPHYS;
-		vp->v_maxio = maxio;
 	}
+	maxio = dev->si_iosize_max;
+	if (!maxio)
+		maxio = DFLTPHYS;
+	if (maxio > MAXPHYS)
+		maxio = MAXPHYS;
+	vp->v_maxio = maxio;
 
 	return (error);
 }
diff --git a/sys/sys/conf.h b/sys/sys/conf.h
index 1f44b6b..16bdb49 100644
--- a/sys/sys/conf.h
+++ b/sys/sys/conf.h
@@ -61,6 +61,7 @@ struct specinfo {
 	struct cdevsw	*si_devsw;
 	void 		*si_devfs;	/* save cookie for devfs operations */
 	void 		*si_bdevfs;	/* XXX block device (should go away) */
+	int		si_iosize_max;	/* maximum I/O size (for physio &al) */
 	union {
 		struct {
 			struct tty *__sit_tty;
@@ -70,7 +71,6 @@ struct specinfo {
 			struct mount *__sid_mountpoint;
 			int __sid_bsize_phys; /* min physical block size */
 			int __sid_bsize_best; /* optimal block size */
-			int __sid_iosize_max;  /* maximum I/O size */
 		} __si_disk;
 	} __si_u;
 };
@@ -80,7 +80,6 @@ struct specinfo {
 #define si_mountpoint	__si_u.__si_disk.__sid_mountpoint
 #define si_bsize_phys	__si_u.__si_disk.__sid_bsize_phys
 #define si_bsize_best	__si_u.__si_disk.__sid_bsize_best
-#define si_iosize_max	__si_u.__si_disk.__sid_iosize_max
 
 /*
  * Exported shorthand
@@ -182,7 +181,7 @@ struct cdevsw {
 	d_dump_t	*d_dump;
 	d_psize_t	*d_psize;
 	u_int		d_flags;
-	int		d_maxio;
+	int		d_bogomaxio;	/* XXX not used */
 	int		d_bmaj;
 };
 
diff --git a/sys/sys/linedisc.h b/sys/sys/linedisc.h
index 1f44b6b..16bdb49 100644
--- a/sys/sys/linedisc.h
+++ b/sys/sys/linedisc.h
@@ -61,6 +61,7 @@ struct specinfo {
 	struct cdevsw	*si_devsw;
 	void 		*si_devfs;	/* save cookie for devfs operations */
 	void 		*si_bdevfs;	/* XXX block device (should go away) */
+	int		si_iosize_max;	/* maximum I/O size (for physio &al) */
 	union {
 		struct {
 			struct tty *__sit_tty;
@@ -70,7 +71,6 @@ struct specinfo {
 			struct mount *__sid_mountpoint;
 			int __sid_bsize_phys; /* min physical block size */
 			int __sid_bsize_best; /* optimal block size */
-			int __sid_iosize_max;  /* maximum I/O size */
 		} __si_disk;
 	} __si_u;
 };
@@ -80,7 +80,6 @@ struct specinfo {
 #define si_mountpoint	__si_u.__si_disk.__sid_mountpoint
 #define si_bsize_phys	__si_u.__si_disk.__sid_bsize_phys
 #define si_bsize_best	__si_u.__si_disk.__sid_bsize_best
-#define si_iosize_max	__si_u.__si_disk.__sid_iosize_max
 
 /*
  * Exported shorthand
@@ -182,7 +181,7 @@ struct cdevsw {
 	d_dump_t	*d_dump;
 	d_psize_t	*d_psize;
 	u_int		d_flags;
-	int		d_maxio;
+	int		d_bogomaxio;	/* XXX not used */
 	int		d_bmaj;
 };