Commit 80ed156a authored by Sebastian Ott's avatar Sebastian Ott Committed by Martin Schwidefsky
Browse files

s390/pci: add locking for fmb access 



Function measurement can be toggled at runtime. Make sure that
all access to the fmb is protected via a mutex.

Signed-off-by: default avatarSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 6001018a

arch/s390/include/asm/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#define PCI_BAR_COUNT	6



#include <linux/pci.h>

#include <linux/mutex.h>

#include <asm-generic/pci.h>

#include <asm-generic/pci-dma-compat.h>

#include <asm/pci_clp.h>
@@ -76,6 +77,7 @@ struct zpci_dev { 
	u8		pft;		/* pci function type */

	u16		domain;



	struct mutex lock;

	u8 pfip[CLP_PFIP_NR_SEGMENTS];	/* pci function internal path */

	u32 uid;			/* user defined id */

	u8 util_str[CLP_UTIL_STR_LEN];	/* utility string */

arch/s390/pci/pci.c

+1 −0
Original line number Diff line number Diff line
@@ -827,6 +827,7 @@ int zpci_create_device(struct zpci_dev *zdev) 
	if (rc)

		goto out;



	mutex_init(&zdev->lock);

	if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {

		rc = zpci_enable_device(zdev);

		if (rc)

arch/s390/pci/pci_debug.c

+9 −6
Original line number Diff line number Diff line
@@ -58,8 +58,12 @@ static int pci_perf_show(struct seq_file *m, void *v) 


	if (!zdev)

		return 0;

	if (!zdev->fmb)



	mutex_lock(&zdev->lock);

	if (!zdev->fmb) {

		mutex_unlock(&zdev->lock);

		return seq_printf(m, "FMB statistics disabled\n");

	}



	/* header */

	seq_printf(m, "FMB @ %p\n", zdev->fmb);
@@ -78,6 +82,7 @@ static int pci_perf_show(struct seq_file *m, void *v) 
				   pci_perf_names[i], *(stat + i));



	pci_sw_counter_show(m);

	mutex_unlock(&zdev->lock);

	return 0;

}
@@ -95,19 +100,17 @@ static ssize_t pci_perf_seq_write(struct file *file, const char __user *ubuf, 
	if (rc)

		return rc;



	mutex_lock(&zdev->lock);

	switch (val) {

	case 0:

		rc = zpci_fmb_disable_device(zdev);

		if (rc)

			return rc;

		break;

	case 1:

		rc = zpci_fmb_enable_device(zdev);

		if (rc)

			return rc;

		break;

	}

	return count;

	mutex_unlock(&zdev->lock);

	return rc ? rc : count;

}



static int pci_perf_seq_open(struct inode *inode, struct file *filp)