Commit 034cd97e authored by Alexander Gordeev's avatar Alexander Gordeev Committed by Bjorn Helgaas
Browse files

PCI/MSI: Remove pci_enable_msi_block() 



There are no users of pci_enable_msi_block() function left.  Obsolete it in
favor of pci_enable_msi_range() and pci_enable_msi_exact() functions.

Previously, we called arch_setup_msi_irqs() once, requesting the same
vector count we passed to arch_msi_check_device().  Now we may call it
several times: if it returns failure, we may retry and request fewer
vectors.

We don't keep track of the vector count we initially passed to
arch_msi_check_device().  We only keep track of the number of vectors
successfully set up by arch_setup_msi_irqs(), and this is what we use to
clean things up when disabling MSI.  Therefore, we assume that
arch_msi_check_device() does nothing that will have to be cleaned up later.

[bhelgaas: changelog]
Signed-off-by: default avatarAlexander Gordeev <agordeev@redhat.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent a30d0108

drivers/pci/msi.c

+33 −46
Original line number Diff line number Diff line
@@ -879,50 +879,6 @@ int pci_msi_vec_count(struct pci_dev *dev) 
}

EXPORT_SYMBOL(pci_msi_vec_count);



/**

 * pci_enable_msi_block - configure device's MSI capability structure

 * @dev: device to configure

 * @nvec: number of interrupts to configure

 *

 * Allocate IRQs for a device with the MSI capability.

 * This function returns a negative errno if an error occurs.  If it

 * is unable to allocate the number of interrupts requested, it returns

 * the number of interrupts it might be able to allocate.  If it successfully

 * allocates at least the number of interrupts requested, it returns 0 and

 * updates the @dev's irq member to the lowest new interrupt number; the

 * other interrupt numbers allocated to this device are consecutive.

 */

int pci_enable_msi_block(struct pci_dev *dev, int nvec)

{

	int status, maxvec;



	if (dev->current_state != PCI_D0)

		return -EINVAL;



	maxvec = pci_msi_vec_count(dev);

	if (maxvec < 0)

		return maxvec;

	if (nvec > maxvec)

		return maxvec;



	status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);

	if (status)

		return status;



	WARN_ON(!!dev->msi_enabled);



	/* Check whether driver already requested MSI-X irqs */

	if (dev->msix_enabled) {

		dev_info(&dev->dev, "can't enable MSI "

			 "(MSI-X already enabled)\n");

		return -EINVAL;

	}



	status = msi_capability_init(dev, nvec);

	return status;

}

EXPORT_SYMBOL(pci_enable_msi_block);



void pci_msi_shutdown(struct pci_dev *dev)

{

	struct msi_desc *desc;
@@ -1128,14 +1084,45 @@ void pci_msi_init_pci_dev(struct pci_dev *dev) 
 **/

int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)

{

	int nvec = maxvec;

	int nvec;

	int rc;



	if (dev->current_state != PCI_D0)

		return -EINVAL;



	WARN_ON(!!dev->msi_enabled);



	/* Check whether driver already requested MSI-X irqs */

	if (dev->msix_enabled) {

		dev_info(&dev->dev,

			 "can't enable MSI (MSI-X already enabled)\n");

		return -EINVAL;

	}



	if (maxvec < minvec)

		return -ERANGE;



	nvec = pci_msi_vec_count(dev);

	if (nvec < 0)

		return nvec;

	else if (nvec < minvec)

		return -EINVAL;

	else if (nvec > maxvec)

		nvec = maxvec;



	do {

		rc = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);

		if (rc < 0) {

			return rc;

		} else if (rc > 0) {

			if (rc < minvec)

				return -ENOSPC;

			nvec = rc;

		}

	} while (rc);



	do {

		rc = pci_enable_msi_block(dev, nvec);

		rc = msi_capability_init(dev, nvec);

		if (rc < 0) {

			return rc;

		} else if (rc > 0) {

include/linux/pci.h

+1 −4
Original line number Diff line number Diff line
@@ -1158,7 +1158,6 @@ struct msix_entry { 


#ifdef CONFIG_PCI_MSI

int pci_msi_vec_count(struct pci_dev *dev);

int pci_enable_msi_block(struct pci_dev *dev, int nvec);

void pci_msi_shutdown(struct pci_dev *dev);

void pci_disable_msi(struct pci_dev *dev);

int pci_msix_vec_count(struct pci_dev *dev);
@@ -1188,8 +1187,6 @@ static inline int pci_enable_msix_exact(struct pci_dev *dev, 
}

#else

static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; }

static inline int pci_enable_msi_block(struct pci_dev *dev, int nvec)

{ return -ENOSYS; }

static inline void pci_msi_shutdown(struct pci_dev *dev) { }

static inline void pci_disable_msi(struct pci_dev *dev) { }

static inline int pci_msix_vec_count(struct pci_dev *dev) { return -ENOSYS; }
@@ -1244,7 +1241,7 @@ static inline void pcie_set_ecrc_checking(struct pci_dev *dev) { } 
static inline void pcie_ecrc_get_policy(char *str) { }

#endif



#define pci_enable_msi(pdev)	pci_enable_msi_block(pdev, 1)

#define pci_enable_msi(pdev)	pci_enable_msi_exact(pdev, 1)



#ifdef CONFIG_HT_IRQ

/* The functions a driver should call */

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