From cd646aba8167fad197a3367eba21f1e9cbbf9634 Mon Sep 17 00:00:00 2001
From: Alexander Motin <mav@FreeBSD.org>
Date: Mon, 12 Jul 2010 12:16:11 +0000
Subject: [PATCH] Revert and remake r209883: Do not grab lock while setting up
 interrupt, as it causes LOR with allocation code. Instead make interrupt
 handler check that CAM bus initialization completed before touching it.

While there, slightly improve attach errors handling.

Reported by:	kib
---
 sys/dev/ata/ata-all.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/sys/dev/ata/ata-all.c b/sys/dev/ata/ata-all.c
index ac94e8ef7b9..3f7f1a9ef3e 100644
--- a/sys/dev/ata/ata-all.c
+++ b/sys/dev/ata/ata-all.c
@@ -185,29 +185,28 @@ ata_attach(device_t dev)
     if (ch->dma.alloc)
 	ch->dma.alloc(dev);
 
-    mtx_lock(&ch->state_mtx);
     /* setup interrupt delivery */
     rid = ATA_IRQ_RID;
     ch->r_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
 				       RF_SHAREABLE | RF_ACTIVE);
     if (!ch->r_irq) {
 	device_printf(dev, "unable to allocate interrupt\n");
-	mtx_unlock(&ch->state_mtx);
 	return ENXIO;
     }
     if ((error = bus_setup_intr(dev, ch->r_irq, ATA_INTR_FLAGS, NULL,
 				ata_interrupt, ch, &ch->ih))) {
+	bus_release_resource(dev, SYS_RES_IRQ, rid, ch->r_irq);
 	device_printf(dev, "unable to setup interrupt\n");
-	goto err1;
+	return error;
     }
 
 #ifndef ATA_CAM
-    mtx_unlock(&ch->state_mtx);
     /* probe and attach devices on this channel unless we are in early boot */
     if (!ata_delayed_attach)
 	ata_identify(dev);
     return (0);
 #else
+	mtx_lock(&ch->state_mtx);
 	/* Create the device queue for our SIM. */
 	devq = cam_simq_alloc(1);
 	if (devq == NULL) {
@@ -220,8 +219,9 @@ ata_attach(device_t dev)
 	    device_get_unit(dev), &ch->state_mtx, 1, 0, devq);
 	if (ch->sim == NULL) {
 		device_printf(dev, "unable to allocate sim\n");
+		cam_simq_free(devq);
 		error = ENOMEM;
-		goto err2;
+		goto err1;
 	}
 	if (xpt_bus_register(ch->sim, dev, 0) != CAM_SUCCESS) {
 		device_printf(dev, "unable to register xpt bus\n");
@@ -241,11 +241,12 @@ err3:
 	xpt_bus_deregister(cam_sim_path(ch->sim));
 err2:
 	cam_sim_free(ch->sim, /*free_devq*/TRUE);
-#endif
+	ch->sim = NULL;
 err1:
-	bus_release_resource(dev, SYS_RES_IRQ, ATA_IRQ_RID, ch->r_irq);
+	bus_release_resource(dev, SYS_RES_IRQ, rid, ch->r_irq);
 	mtx_unlock(&ch->state_mtx);
 	return (error);
+#endif
 }
 
 int
@@ -283,6 +284,7 @@ ata_detach(device_t dev)
 	xpt_free_path(ch->path);
 	xpt_bus_deregister(cam_sim_path(ch->sim));
 	cam_sim_free(ch->sim, /*free_devq*/TRUE);
+	ch->sim = NULL;
 	mtx_unlock(&ch->state_mtx);
 #endif
 
@@ -309,9 +311,12 @@ ata_conn_event(void *context, int dummy)
 	union ccb *ccb;
 
 	mtx_lock(&ch->state_mtx);
+	if (ch->sim == NULL) {
+		mtx_unlock(&ch->state_mtx);
+		return;
+	}
 	ata_reinit(dev);
-	mtx_unlock(&ch->state_mtx);
-	if ((ccb = xpt_alloc_ccb()) == NULL)
+	if ((ccb = xpt_alloc_ccb_nowait()) == NULL)
 		return;
 	if (xpt_create_path(&ccb->ccb_h.path, NULL,
 	    cam_sim_path(ch->sim),
@@ -320,6 +325,7 @@ ata_conn_event(void *context, int dummy)
 		return;
 	}
 	xpt_rescan(ccb);
+	mtx_unlock(&ch->state_mtx);
 #else
 	ata_reinit(dev);
 #endif