From michael@ozlabs.org Thu Apr 5 00:19:18 2007 From: Michael Ellerman Date: Thu, 05 Apr 2007 17:19:10 +1000 Subject: [PATCH 5/9] MSI: Use a list instead of the custom link structure To: linux-pci@atrey.karlin.mff.cuni.cz Cc: Greg Kroah-Hartman , Eric W. Biederman , Benjamin Herrenschmidt , David S. Miller Message-ID: <20070405071912.8B9F7DDE48@ozlabs.org> The msi descriptors are linked together with what looks a lot like a linked list, but isn't a struct list_head list. Make it one. The only complication is that previously we walked a list of irqs, and got the descriptor for each with get_irq_msi(). Now we have a list of descriptors and need to get the irq out of it, so it needs to be in the actual struct msi_desc. We use 0 to indicate no irq is setup. Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- drivers/pci/msi.c | 66 ++++++++++++++++++---------------------------------- drivers/pci/pci.h | 2 + drivers/pci/probe.c | 2 + include/linux/msi.h | 8 +++--- include/linux/pci.h | 1 5 files changed, 33 insertions(+), 46 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -218,7 +218,8 @@ static struct msi_desc* alloc_msi_entry( if (!entry) return NULL; - entry->link.tail = entry->link.head = 0; /* single message */ + INIT_LIST_HEAD(&entry->list); + entry->irq = 0; entry->dev = NULL; return entry; @@ -253,7 +254,6 @@ static void __pci_restore_msi_state(stru static void __pci_restore_msix_state(struct pci_dev *dev) { int pos; - int irq, head, tail = 0; struct msi_desc *entry; u16 control; @@ -263,18 +263,14 @@ static void __pci_restore_msix_state(str /* route the table */ pci_intx(dev, 0); /* disable intx */ msix_set_enable(dev, 0); - irq = head = dev->first_msi_irq; - entry = get_irq_msi(irq); - pos = entry->msi_attrib.pos; - while (head != tail) { - entry = get_irq_msi(irq); - write_msi_msg(irq, &entry->msg); - msi_set_mask_bit(irq, entry->msi_attrib.masked); - tail = entry->link.tail; - irq = tail; + list_for_each_entry(entry, &dev->msi_list, list) { + write_msi_msg(entry->irq, &entry->msg); + msi_set_mask_bit(entry->irq, entry->msi_attrib.masked); } + entry = get_irq_msi(dev->first_msi_irq); + pos = entry->msi_attrib.pos; pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); control &= ~PCI_MSIX_FLAGS_MASKALL; control |= PCI_MSIX_FLAGS_ENABLE; @@ -343,8 +339,8 @@ static int msi_capability_init(struct pc kfree(entry); return irq; } - entry->link.head = irq; - entry->link.tail = irq; + entry->irq = irq; + list_add(&entry->list, &dev->msi_list); dev->first_msi_irq = irq; set_irq_msi(irq, entry); @@ -370,8 +366,8 @@ static int msi_capability_init(struct pc static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, int nvec) { - struct msi_desc *head = NULL, *tail = NULL, *entry = NULL; - int irq, pos, i, j, nr_entries, temp = 0; + struct msi_desc *entry; + int irq, pos, i, j, nr_entries; unsigned long phys_addr; u32 table_offset; u16 control; @@ -416,19 +412,9 @@ static int msix_capability_init(struct p kfree(entry); break; } + entry->irq = irq; entries[i].vector = irq; - if (!head) { - entry->link.head = irq; - entry->link.tail = irq; - head = entry; - } else { - entry->link.head = temp; - entry->link.tail = tail->link.tail; - tail->link.tail = irq; - head->link.head = irq; - } - temp = irq; - tail = entry; + list_add(&entry->list, &dev->msi_list); set_irq_msi(irq, entry); } @@ -557,7 +543,7 @@ EXPORT_SYMBOL(pci_disable_msi); static int msi_free_irq(struct pci_dev* dev, int irq) { struct msi_desc *entry; - int head, entry_nr, type; + int entry_nr, type; void __iomem *base; BUG_ON(irq_has_action(irq)); @@ -568,10 +554,8 @@ static int msi_free_irq(struct pci_dev* } type = entry->msi_attrib.type; entry_nr = entry->msi_attrib.entry_nr; - head = entry->link.head; base = entry->mask_base; - get_irq_msi(entry->link.head)->link.tail = entry->link.tail; - get_irq_msi(entry->link.tail)->link.head = entry->link.head; + list_del(&entry->list); arch_teardown_msi_irq(irq); kfree(entry); @@ -580,7 +564,7 @@ static int msi_free_irq(struct pci_dev* writel(1, base + entry_nr * PCI_MSIX_ENTRY_SIZE + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); - if (head == irq) + if (list_empty(&dev->msi_list)) iounmap(base); } @@ -646,17 +630,10 @@ EXPORT_SYMBOL(pci_enable_msix); static void msix_free_all_irqs(struct pci_dev *dev) { - int irq, head, tail = 0; - - irq = head = dev->first_msi_irq; - while (head != tail) { - tail = get_irq_msi(irq)->link.tail; + struct msi_desc *entry; - if (irq != head) - msi_free_irq(dev, irq); - irq = tail; - } - msi_free_irq(dev, irq); + list_for_each_entry(entry, &dev->msi_list, list) + msi_free_irq(dev, entry->irq); dev->first_msi_irq = 0; } @@ -699,6 +676,11 @@ void pci_no_msi(void) pci_msi_enable = 0; } +void pci_msi_init_pci_dev(struct pci_dev *dev) +{ + INIT_LIST_HEAD(&dev->msi_list); +} + /* Arch hooks */ --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -47,8 +47,10 @@ extern unsigned int pci_pm_d3_delay; #ifdef CONFIG_PCI_MSI void pci_no_msi(void); +extern void pci_msi_init_pci_dev(struct pci_dev *dev); #else static inline void pci_no_msi(void) { } +static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { } #endif #if defined(CONFIG_PCI_MSI) && defined(CONFIG_PM) --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -855,6 +855,8 @@ struct pci_dev *alloc_pci_dev(void) INIT_LIST_HEAD(&dev->global_list); INIT_LIST_HEAD(&dev->bus_list); + pci_msi_init_pci_dev(dev); + return dev; } EXPORT_SYMBOL(alloc_pci_dev); --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -1,6 +1,8 @@ #ifndef LINUX_MSI_H #define LINUX_MSI_H +#include + struct msi_msg { u32 address_lo; /* low 32 bits of msi message address */ u32 address_hi; /* high 32 bits of msi message address */ @@ -24,10 +26,8 @@ struct msi_desc { unsigned default_irq; /* default pre-assigned irq */ }msi_attrib; - struct { - __u16 head; - __u16 tail; - }link; + unsigned int irq; + struct list_head list; void __iomem *mask_base; struct pci_dev *dev; --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -190,6 +190,7 @@ struct pci_dev { struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */ #ifdef CONFIG_PCI_MSI unsigned int first_msi_irq; + struct list_head msi_list; #endif };