[PATCH v4 31/43] hpsa: call pci_release_regions after pci_disable_device

[Don Brace <don.brace@pmcs.com>]

From: Robert Elliott <elliott@hp.com>

Despite the fact that PCI devices are enabled in this order:
    1. pci_enable_device
    2. pci_request_regions

    Documentation/PCI/pci.txt specifies that they be undone
    in this order
    1. pci_disable_device
    2. pci_release_regions

    Tested by injecting error in the call to pci_enable_device
    in hpsa_init_one -> hpsa_pci_init:
    [    9.095001] hpsa 0000:04:00.0: failed to enable PCI device
    [    9.095005] hpsa: probe of 0000:04:00.0 failed with error -22
    (-22 is -EINVAL)
    and then in the call pci_request_regions:
    [    9.178623] hpsa 0000:04:00.0: failed to obtain PCI resources
    [    9.178671] hpsa: probe of 0000:04:00.0 failed with error -16
    (-16 is -EBUSY)

    and then by adding
        reset_devices
    to the kernel command line and inject errors into the two
    calls to pci_enable_device and the call to pci_request_regions
    in hpsa_init_one -> hpsa_init_reset_devices.

    (inject on 6th call, 1st to hpsa2)
    [   62.413750] hpsa 0000:04:00.0: Failed to enable PCI device

    (inject on 7th call, 2nd to hpsa2)
    [   62.807571] hpsa 0000:04:00.0: failed to enable device.

    (inject on 8th call, 3rd to hpsa2)
    [   62.697198] hpsa 0000:04:00.0: failed to obtain PCI resources
    [   62.697234] hpsa: probe of 0000:04:00.0 failed with error -16

    The reset_devices path calls return -ENODEV on failure
    rather than passing the result, which apparently doesn't
    cause the pci driver to print anything.

Reviewed-by: Scott Teel <scott.teel@pmcs.com>
Reviewed-by: Kevin Barnett <kevin.barnett@pmcs.com>
Signed-off-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Don Brace < don.brace@pmcs.com>
---
 drivers/scsi/hpsa.c |   17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 5e12520..8aeef06 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -7048,8 +7048,12 @@ static void hpsa_free_pci_init(struct ctlr_info *h)
 	iounmap(h->vaddr);			/* pci_init 3 */
 	h->vaddr = NULL;
 	hpsa_disable_interrupt_mode(h);		/* pci_init 2 */
-	pci_release_regions(h->pdev);		/* pci_init 2 */
+	/*
+	 * call pci_disable_device before pci_release_regions per
+	 * Documentation/PCI/pci.txt
+	 */
 	pci_disable_device(h->pdev);		/* pci_init 1 */
+	pci_release_regions(h->pdev);		/* pci_init 2 */
 }
 
 /* several items must be freed later */
@@ -7072,6 +7076,7 @@ static int hpsa_pci_init(struct ctlr_info *h)
 	err = pci_enable_device(h->pdev);
 	if (err) {
 		dev_err(&h->pdev->dev, "failed to enable PCI device\n");
+		pci_disable_device(h->pdev);
 		return err;
 	}
 
@@ -7079,7 +7084,8 @@ static int hpsa_pci_init(struct ctlr_info *h)
 	if (err) {
 		dev_err(&h->pdev->dev,
 			"failed to obtain PCI resources\n");
-		goto clean1;	/* pci */
+		pci_disable_device(h->pdev);
+		return err;
 	}
 
 	pci_set_master(h->pdev);
@@ -7120,9 +7126,12 @@ clean3:	/* vaddr, intmode+region, pci */
 	h->vaddr = NULL;
 clean2:	/* intmode+region, pci */
 	hpsa_disable_interrupt_mode(h);
-	pci_release_regions(h->pdev);
-clean1:	/* pci */
+	/*
+	 * call pci_disable_device before pci_release_regions per
+	 * Documentation/PCI/pci.txt
+	 */
 	pci_disable_device(h->pdev);
+	pci_release_regions(h->pdev);
 	return err;
 }