diff options
Diffstat (limited to 'drivers/pci/msi.c')
| -rw-r--r-- | drivers/pci/msi.c | 498 |
1 files changed, 312 insertions, 186 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 2c1075213be..13f3d303727 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -10,7 +10,6 @@ #include <linux/mm.h> #include <linux/irq.h> #include <linux/interrupt.h> -#include <linux/init.h> #include <linux/export.h> #include <linux/ioport.h> #include <linux/pci.h> @@ -30,20 +29,44 @@ static int pci_msi_enable = 1; /* Arch hooks */ -#ifndef arch_msi_check_device -int arch_msi_check_device(struct pci_dev *dev, int nvec, int type) +int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) { + struct msi_chip *chip = dev->bus->msi; + int err; + + if (!chip || !chip->setup_irq) + return -EINVAL; + + err = chip->setup_irq(chip, dev, desc); + if (err < 0) + return err; + + irq_set_chip_data(desc->irq, chip); + return 0; } -#endif -#ifndef arch_setup_msi_irqs -# define arch_setup_msi_irqs default_setup_msi_irqs -# define HAVE_DEFAULT_MSI_SETUP_IRQS -#endif +void __weak arch_teardown_msi_irq(unsigned int irq) +{ + struct msi_chip *chip = irq_get_chip_data(irq); + + if (!chip || !chip->teardown_irq) + return; + + chip->teardown_irq(chip, irq); +} + +int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type) +{ + struct msi_chip *chip = dev->bus->msi; + + if (!chip || !chip->check_device) + return 0; + + return chip->check_device(chip, dev, nvec, type); +} -#ifdef HAVE_DEFAULT_MSI_SETUP_IRQS -int default_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) { struct msi_desc *entry; int ret; @@ -65,14 +88,11 @@ int default_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) return 0; } -#endif - -#ifndef arch_teardown_msi_irqs -# define arch_teardown_msi_irqs default_teardown_msi_irqs -# define HAVE_DEFAULT_MSI_TEARDOWN_IRQS -#endif -#ifdef HAVE_DEFAULT_MSI_TEARDOWN_IRQS +/* + * We have a default implementation available as a separate non-weak + * function, as it is used by the Xen x86 PCI code + */ void default_teardown_msi_irqs(struct pci_dev *dev) { struct msi_desc *entry; @@ -81,20 +101,21 @@ void default_teardown_msi_irqs(struct pci_dev *dev) int i, nvec; if (entry->irq == 0) continue; - nvec = 1 << entry->msi_attrib.multiple; + if (entry->nvec_used) + nvec = entry->nvec_used; + else + nvec = 1 << entry->msi_attrib.multiple; for (i = 0; i < nvec; i++) arch_teardown_msi_irq(entry->irq + i); } } -#endif -#ifndef arch_restore_msi_irqs -# define arch_restore_msi_irqs default_restore_msi_irqs -# define HAVE_DEFAULT_MSI_RESTORE_IRQS -#endif +void __weak arch_teardown_msi_irqs(struct pci_dev *dev) +{ + return default_teardown_msi_irqs(dev); +} -#ifdef HAVE_DEFAULT_MSI_RESTORE_IRQS -void default_restore_msi_irqs(struct pci_dev *dev, int irq) +static void default_restore_msi_irq(struct pci_dev *dev, int irq) { struct msi_desc *entry; @@ -111,7 +132,11 @@ void default_restore_msi_irqs(struct pci_dev *dev, int irq) if (entry) write_msi_msg(irq, &entry->msg); } -#endif + +void __weak arch_restore_msi_irqs(struct pci_dev *dev) +{ + return default_restore_msi_irqs(dev); +} static void msi_set_enable(struct pci_dev *dev, int enable) { @@ -159,7 +184,7 @@ static inline __attribute_const__ u32 msi_enabled_mask(u16 control) * reliably as devices without an INTx disable bit will then generate a * level IRQ which will never be cleared. */ -static u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) +u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { u32 mask_bits = desc->masked; @@ -173,9 +198,14 @@ static u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) return mask_bits; } +__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) +{ + return default_msi_mask_irq(desc, mask, flag); +} + static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { - desc->masked = __msi_mask_irq(desc, mask, flag); + desc->masked = arch_msi_mask_irq(desc, mask, flag); } /* @@ -185,7 +215,7 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) * file. This saves a few milliseconds when initialising devices with lots * of MSI-X interrupts. */ -static u32 __msix_mask_irq(struct msi_desc *desc, u32 flag) +u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag) { u32 mask_bits = desc->masked; unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + @@ -198,12 +228,15 @@ static u32 __msix_mask_irq(struct msi_desc *desc, u32 flag) return mask_bits; } -static void msix_mask_irq(struct msi_desc *desc, u32 flag) +__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag) { - desc->masked = __msix_mask_irq(desc, flag); + return default_msix_mask_irq(desc, flag); } -#ifdef CONFIG_GENERIC_HARDIRQS +static void msix_mask_irq(struct msi_desc *desc, u32 flag) +{ + desc->masked = arch_msix_mask_irq(desc, flag); +} static void msi_set_mask_bit(struct irq_data *data, u32 flag) { @@ -228,7 +261,14 @@ void unmask_msi_irq(struct irq_data *data) msi_set_mask_bit(data, 0); } -#endif /* CONFIG_GENERIC_HARDIRQS */ +void default_restore_msi_irqs(struct pci_dev *dev) +{ + struct msi_desc *entry; + + list_for_each_entry(entry, &dev->msi_list, list) { + default_restore_msi_irq(dev, entry->irq); + } +} void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg) { @@ -331,16 +371,20 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg) static void free_msi_irqs(struct pci_dev *dev) { struct msi_desc *entry, *tmp; + struct attribute **msi_attrs; + struct device_attribute *dev_attr; + int count = 0; list_for_each_entry(entry, &dev->msi_list, list) { int i, nvec; if (!entry->irq) continue; - nvec = 1 << entry->msi_attrib.multiple; -#ifdef CONFIG_GENERIC_HARDIRQS + if (entry->nvec_used) + nvec = entry->nvec_used; + else + nvec = 1 << entry->msi_attrib.multiple; for (i = 0; i < nvec; i++) BUG_ON(irq_has_action(entry->irq + i)); -#endif } arch_teardown_msi_irqs(dev); @@ -365,6 +409,22 @@ static void free_msi_irqs(struct pci_dev *dev) list_del(&entry->list); kfree(entry); } + + if (dev->msi_irq_groups) { + sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups); + msi_attrs = dev->msi_irq_groups[0]->attrs; + while (msi_attrs[count]) { + dev_attr = container_of(msi_attrs[count], + struct device_attribute, attr); + kfree(dev_attr->attr.name); + kfree(dev_attr); + ++count; + } + kfree(msi_attrs); + kfree(dev->msi_irq_groups[0]); + kfree(dev->msi_irq_groups); + dev->msi_irq_groups = NULL; + } } static struct msi_desc *alloc_msi_entry(struct pci_dev *dev) @@ -397,7 +457,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev) pci_intx_for_msi(dev, 0); msi_set_enable(dev, 0); - arch_restore_msi_irqs(dev, dev->irq); + arch_restore_msi_irqs(dev); pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); msi_mask_irq(entry, msi_capable_mask(control), entry->masked); @@ -422,8 +482,8 @@ static void __pci_restore_msix_state(struct pci_dev *dev) control |= PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL; pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); + arch_restore_msi_irqs(dev); list_for_each_entry(entry, &dev->msi_list, list) { - arch_restore_msi_irqs(dev, entry->irq); msix_mask_irq(entry, entry->masked); } @@ -438,95 +498,99 @@ void pci_restore_msi_state(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(pci_restore_msi_state); - -#define to_msi_attr(obj) container_of(obj, struct msi_attribute, attr) -#define to_msi_desc(obj) container_of(obj, struct msi_desc, kobj) - -struct msi_attribute { - struct attribute attr; - ssize_t (*show)(struct msi_desc *entry, struct msi_attribute *attr, - char *buf); - ssize_t (*store)(struct msi_desc *entry, struct msi_attribute *attr, - const char *buf, size_t count); -}; - -static ssize_t show_msi_mode(struct msi_desc *entry, struct msi_attribute *atr, +static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%s\n", entry->msi_attrib.is_msix ? "msix" : "msi"); -} - -static ssize_t msi_irq_attr_show(struct kobject *kobj, - struct attribute *attr, char *buf) -{ - struct msi_attribute *attribute = to_msi_attr(attr); - struct msi_desc *entry = to_msi_desc(kobj); - - if (!attribute->show) - return -EIO; - - return attribute->show(entry, attribute, buf); -} - -static const struct sysfs_ops msi_irq_sysfs_ops = { - .show = msi_irq_attr_show, -}; - -static struct msi_attribute mode_attribute = - __ATTR(mode, S_IRUGO, show_msi_mode, NULL); - - -static struct attribute *msi_irq_default_attrs[] = { - &mode_attribute.attr, - NULL -}; + struct pci_dev *pdev = to_pci_dev(dev); + struct msi_desc *entry; + unsigned long irq; + int retval; -static void msi_kobj_release(struct kobject *kobj) -{ - struct msi_desc *entry = to_msi_desc(kobj); + retval = kstrtoul(attr->attr.name, 10, &irq); + if (retval) + return retval; - pci_dev_put(entry->dev); + list_for_each_entry(entry, &pdev->msi_list, list) { + if (entry->irq == irq) { + return sprintf(buf, "%s\n", + entry->msi_attrib.is_msix ? "msix" : "msi"); + } + } + return -ENODEV; } -static struct kobj_type msi_irq_ktype = { - .release = msi_kobj_release, - .sysfs_ops = &msi_irq_sysfs_ops, - .default_attrs = msi_irq_default_attrs, -}; - static int populate_msi_sysfs(struct pci_dev *pdev) { + struct attribute **msi_attrs; + struct attribute *msi_attr; + struct device_attribute *msi_dev_attr; + struct attribute_group *msi_irq_group; + const struct attribute_group **msi_irq_groups; struct msi_desc *entry; - struct kobject *kobj; - int ret; + int ret = -ENOMEM; + int num_msi = 0; int count = 0; - pdev->msi_kset = kset_create_and_add("msi_irqs", NULL, &pdev->dev.kobj); - if (!pdev->msi_kset) - return -ENOMEM; + /* Determine how many msi entries we have */ + list_for_each_entry(entry, &pdev->msi_list, list) { + ++num_msi; + } + if (!num_msi) + return 0; + /* Dynamically create the MSI attributes for the PCI device */ + msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL); + if (!msi_attrs) + return -ENOMEM; list_for_each_entry(entry, &pdev->msi_list, list) { - kobj = &entry->kobj; - kobj->kset = pdev->msi_kset; - pci_dev_get(pdev); - ret = kobject_init_and_add(kobj, &msi_irq_ktype, NULL, - "%u", entry->irq); - if (ret) - goto out_unroll; - - count++; + msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL); + if (!msi_dev_attr) + goto error_attrs; + msi_attrs[count] = &msi_dev_attr->attr; + + sysfs_attr_init(&msi_dev_attr->attr); + msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d", + entry->irq); + if (!msi_dev_attr->attr.name) + goto error_attrs; + msi_dev_attr->attr.mode = S_IRUGO; + msi_dev_attr->show = msi_mode_show; + ++count; } + msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL); + if (!msi_irq_group) + goto error_attrs; + msi_irq_group->name = "msi_irqs"; + msi_irq_group->attrs = msi_attrs; + + msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL); + if (!msi_irq_groups) + goto error_irq_group; + msi_irq_groups[0] = msi_irq_group; + + ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups); + if (ret) + goto error_irq_groups; + pdev->msi_irq_groups = msi_irq_groups; + return 0; -out_unroll: - list_for_each_entry(entry, &pdev->msi_list, list) { - if (!count) - break; - kobject_del(&entry->kobj); - kobject_put(&entry->kobj); - count--; +error_irq_groups: + kfree(msi_irq_groups); +error_irq_group: + kfree(msi_irq_group); +error_attrs: + count = 0; + msi_attr = msi_attrs[count]; + while (msi_attr) { + msi_dev_attr = container_of(msi_attr, struct device_attribute, attr); + kfree(msi_attr->name); + kfree(msi_dev_attr); + ++count; + msi_attr = msi_attrs[count]; } + kfree(msi_attrs); return ret; } @@ -696,7 +760,7 @@ static int msix_capability_init(struct pci_dev *dev, ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX); if (ret) - goto error; + goto out_avail; /* * Some devices require MSI-X to be enabled before we can touch the @@ -709,10 +773,8 @@ static int msix_capability_init(struct pci_dev *dev, msix_program_entries(dev, entries); ret = populate_msi_sysfs(dev); - if (ret) { - ret = 0; - goto error; - } + if (ret) + goto out_free; /* Set MSI-X enabled bits and unmask the function */ pci_intx_for_msi(dev, 0); @@ -723,7 +785,7 @@ static int msix_capability_init(struct pci_dev *dev, return 0; -error: +out_avail: if (ret < 0) { /* * If we had some success, report the number of irqs @@ -740,6 +802,7 @@ error: ret = avail; } +out_free: free_msi_irqs(dev); return ret; @@ -751,7 +814,7 @@ error: * @nvec: how many MSIs have been requested ? * @type: are we checking for MSI or MSI-X ? * - * Look at global flags, the device itself, and its parent busses + * Look at global flags, the device itself, and its parent buses * to determine if MSI/-X are supported for the device. If MSI/-X is * supported return 0, else return an error code. **/ @@ -791,52 +854,18 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type) } /** - * pci_enable_msi_block - configure device's MSI capability structure - * @dev: device to configure - * @nvec: number of interrupts to configure + * pci_msi_vec_count - Return the number of MSI vectors a device can send + * @dev: device to report about * - * 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, unsigned int nvec) -{ - int status, maxvec; - u16 msgctl; - - if (!dev->msi_cap) - return -EINVAL; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); - maxvec = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); - 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); - -int pci_enable_msi_block_auto(struct pci_dev *dev, unsigned int *maxvec) + * This function returns the number of MSI vectors a device requested via + * Multiple Message Capable register. It returns a negative errno if the + * device is not capable sending MSI interrupts. Otherwise, the call succeeds + * and returns a power of two, up to a maximum of 2^5 (32), according to the + * MSI specification. + **/ +int pci_msi_vec_count(struct pci_dev *dev) { - int ret, nvec; + int ret; u16 msgctl; if (!dev->msi_cap) @@ -845,19 +874,9 @@ int pci_enable_msi_block_auto(struct pci_dev *dev, unsigned int *maxvec) pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); - if (maxvec) - *maxvec = ret; - - do { - nvec = ret; - ret = pci_enable_msi_block(dev, nvec); - } while (ret > 0); - - if (ret < 0) - return ret; - return nvec; + return ret; } -EXPORT_SYMBOL(pci_enable_msi_block_auto); +EXPORT_SYMBOL(pci_msi_vec_count); void pci_msi_shutdown(struct pci_dev *dev) { @@ -879,7 +898,7 @@ void pci_msi_shutdown(struct pci_dev *dev) pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl); mask = msi_capable_mask(ctrl); /* Keep cached state to be restored */ - __msi_mask_irq(desc, mask, ~mask); + arch_msi_mask_irq(desc, mask, ~mask); /* Restore dev->irq to its default pin-assertion irq */ dev->irq = desc->msi_attrib.default_irq; @@ -892,25 +911,28 @@ void pci_disable_msi(struct pci_dev *dev) pci_msi_shutdown(dev); free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; } EXPORT_SYMBOL(pci_disable_msi); /** - * pci_msix_table_size - return the number of device's MSI-X table entries + * pci_msix_vec_count - return the number of device's MSI-X table entries * @dev: pointer to the pci_dev data structure of MSI-X device function - */ -int pci_msix_table_size(struct pci_dev *dev) + * This function returns the number of device's MSI-X table entries and + * therefore the number of MSI-X vectors device is capable of sending. + * It returns a negative errno if the device is not capable of sending MSI-X + * interrupts. + **/ +int pci_msix_vec_count(struct pci_dev *dev) { u16 control; if (!dev->msix_cap) - return 0; + return -EINVAL; pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); return msix_table_size(control); } +EXPORT_SYMBOL(pci_msix_vec_count); /** * pci_enable_msix - configure device's MSI-X capability structure @@ -932,14 +954,16 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) int status, nr_entries; int i, j; - if (!entries || !dev->msix_cap) + if (!entries || !dev->msix_cap || dev->current_state != PCI_D0) return -EINVAL; status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX); if (status) return status; - nr_entries = pci_msix_table_size(dev); + nr_entries = pci_msix_vec_count(dev); + if (nr_entries < 0) + return nr_entries; if (nvec > nr_entries) return nr_entries; @@ -956,8 +980,7 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) /* Check whether driver already requested for MSI irq */ if (dev->msi_enabled) { - dev_info(&dev->dev, "can't enable MSI-X " - "(MSI IRQ already assigned)\n"); + dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n"); return -EINVAL; } status = msix_capability_init(dev, entries, nvec); @@ -975,7 +998,7 @@ void pci_msix_shutdown(struct pci_dev *dev) /* Return the device with MSI-X masked as initial states */ list_for_each_entry(entry, &dev->msi_list, list) { /* Keep cached states to be restored */ - __msix_mask_irq(entry, 1); + arch_msix_mask_irq(entry, 1); } msix_set_enable(dev, 0); @@ -990,8 +1013,6 @@ void pci_disable_msix(struct pci_dev *dev) pci_msix_shutdown(dev); free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; } EXPORT_SYMBOL(pci_disable_msix); @@ -1046,3 +1067,108 @@ void pci_msi_init_pci_dev(struct pci_dev *dev) if (dev->msix_cap) msix_set_enable(dev, 0); } + +/** + * pci_enable_msi_range - configure device's MSI capability structure + * @dev: device to configure + * @minvec: minimal number of interrupts to configure + * @maxvec: maximum number of interrupts to configure + * + * This function tries to allocate a maximum possible number of interrupts in a + * range between @minvec and @maxvec. It returns a negative errno if an error + * occurs. If it succeeds, it returns the actual number of interrupts allocated + * 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_range(struct pci_dev *dev, int minvec, int 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 = msi_capability_init(dev, nvec); + if (rc < 0) { + return rc; + } else if (rc > 0) { + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } + } while (rc); + + return nvec; +} +EXPORT_SYMBOL(pci_enable_msi_range); + +/** + * pci_enable_msix_range - configure device's MSI-X capability structure + * @dev: pointer to the pci_dev data structure of MSI-X device function + * @entries: pointer to an array of MSI-X entries + * @minvec: minimum number of MSI-X irqs requested + * @maxvec: maximum number of MSI-X irqs requested + * + * Setup the MSI-X capability structure of device function with a maximum + * possible number of interrupts in the range between @minvec and @maxvec + * upon its software driver call to request for MSI-X mode enabled on its + * hardware device function. It returns a negative errno if an error occurs. + * If it succeeds, it returns the actual number of interrupts allocated and + * indicates the successful configuration of MSI-X capability structure + * with new allocated MSI-X interrupts. + **/ +int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, + int minvec, int maxvec) +{ + int nvec = maxvec; + int rc; + + if (maxvec < minvec) + return -ERANGE; + + do { + rc = pci_enable_msix(dev, entries, nvec); + if (rc < 0) { + return rc; + } else if (rc > 0) { + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } + } while (rc); + + return nvec; +} +EXPORT_SYMBOL(pci_enable_msix_range); |