From f44116ae881868ab72274df1eff48fdbde9898af Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 26 Feb 2014 11:25:58 -0700 Subject: PCI: Remove pci_find_parent_resource() use for allocation If the resource hasn't been allocated yet, pci_find_parent_resource() is documented as returning the region "where it should be allocated from." This is impossible in general because there may be several candidates: a prefetchable BAR can be put in either a prefetchable or non-prefetchable window, a transparent bridge may have overlapping positively- and subtractively-decoded windows, and a root bus may have several windows of the same type. Allocation should be done by pci_bus_alloc_resource(), which iterates through all bus resources and looks for the best match, e.g., one with the desired prefetchability attributes, and falls back to less-desired possibilities. The only valid use of pci_find_parent_resource() is to find the parent of an already-allocated resource so we can claim it via request_resource(), and all we need for that is a bus region of the correct type that contains the resource. Note that like 8c8def26bfaa ("PCI: allow matching of prefetchable resources to non-prefetchable windows"), this depends on pci_bus_for_each_resource() iterating through positively-decoded regions before subtractively-decoded ones. We prefer not to return a subtractively-decoded region because requesting from it will likely conflict with the overlapping positively- decoded window (see Launchpad report below). Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/424142 Signed-off-by: Bjorn Helgaas CC: Linus Torvalds --- drivers/pci/pci.c | 39 +++++++++++++++++++++++---------------- 1 file changed, 23 insertions(+), 16 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1febe90831b..99293fa40db 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -401,33 +401,40 @@ EXPORT_SYMBOL_GPL(pci_find_ht_capability); * @res: child resource record for which parent is sought * * For given resource region of given device, return the resource - * region of parent bus the given region is contained in or where - * it should be allocated from. + * region of parent bus the given region is contained in. */ struct resource * pci_find_parent_resource(const struct pci_dev *dev, struct resource *res) { const struct pci_bus *bus = dev->bus; + struct resource *r; int i; - struct resource *best = NULL, *r; pci_bus_for_each_resource(bus, r, i) { if (!r) continue; - if (res->start && !(res->start >= r->start && res->end <= r->end)) - continue; /* Not contained */ - if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM)) - continue; /* Wrong type */ - if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH)) - return r; /* Exact match */ - /* We can't insert a non-prefetch resource inside a prefetchable parent .. */ - if (r->flags & IORESOURCE_PREFETCH) - continue; - /* .. but we can put a prefetchable resource inside a non-prefetchable one */ - if (!best) - best = r; + if (res->start && resource_contains(r, res)) { + + /* + * If the window is prefetchable but the BAR is + * not, the allocator made a mistake. + */ + if (r->flags & IORESOURCE_PREFETCH && + !(res->flags & IORESOURCE_PREFETCH)) + return NULL; + + /* + * If we're below a transparent bridge, there may + * be both a positively-decoded aperture and a + * subtractively-decoded region that contain the BAR. + * We want the positively-decoded one, so this depends + * on pci_bus_for_each_resource() giving us those + * first. + */ + return r; + } } - return best; + return NULL; } /** -- cgit v1.2.3-70-g09d2 From bd064f0a231af336218838474ea45a64f1672190 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 26 Feb 2014 11:25:58 -0700 Subject: PCI: Mark resources as IORESOURCE_UNSET if we can't assign them When assigning addresses to resources, mark them with IORESOURCE_UNSET before we start and clear IORESOURCE_UNSET if assignment is successful. That means that if we print the resource during assignment, we will show the size, not a meaningless address. Also, clear IORESOURCE_UNSET if we do assign an address, so we print the address when it is valid. Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 2 ++ drivers/pci/quirks.c | 5 +++++ drivers/pci/rom.c | 2 ++ drivers/pci/setup-res.c | 4 ++++ 4 files changed, 13 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 99293fa40db..dc9ce62be7a 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4244,6 +4244,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) "Rounding up size of resource #%d to %#llx.\n", i, (unsigned long long)size); } + r->flags |= IORESOURCE_UNSET; r->end = size - 1; r->start = 0; } @@ -4257,6 +4258,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) r = &dev->resource[i]; if (!(r->flags & IORESOURCE_MEM)) continue; + r->flags |= IORESOURCE_UNSET; r->end = resource_size(r) - 1; r->start = 0; } diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 5cb726c193d..6e596ab77fb 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -296,6 +296,7 @@ static void quirk_s3_64M(struct pci_dev *dev) struct resource *r = &dev->resource[0]; if ((r->start & 0x3ffffff) || r->end != r->start + 0x3ffffff) { + r->flags |= IORESOURCE_UNSET; r->start = 0; r->end = 0x3ffffff; } @@ -937,6 +938,8 @@ DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_FE_GATE_700C static void quirk_dunord(struct pci_dev *dev) { struct resource *r = &dev->resource [1]; + + r->flags |= IORESOURCE_UNSET; r->start = 0; r->end = 0xffffff; } @@ -1740,6 +1743,7 @@ static void quirk_tc86c001_ide(struct pci_dev *dev) struct resource *r = &dev->resource[0]; if (r->start & 0x8) { + r->flags |= IORESOURCE_UNSET; r->start = 0; r->end = 0xf; } @@ -1769,6 +1773,7 @@ static void quirk_plx_pci9050(struct pci_dev *dev) dev_info(&dev->dev, "Re-allocating PLX PCI 9050 BAR %u to length 256 to avoid bit 7 bug\n", bar); + r->flags |= IORESOURCE_UNSET; r->start = 0; r->end = 0xff; } diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c index 5d595724e5f..c1839450d4d 100644 --- a/drivers/pci/rom.c +++ b/drivers/pci/rom.c @@ -197,8 +197,10 @@ void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom) void pci_cleanup_rom(struct pci_dev *pdev) { struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; + if (res->flags & IORESOURCE_ROM_COPY) { kfree((void*)(unsigned long)res->start); + res->flags |= IORESOURCE_UNSET; res->flags &= ~IORESOURCE_ROM_COPY; res->start = 0; res->end = 0; diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index 5c060b152ce..0474b0217fd 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c @@ -263,6 +263,7 @@ int pci_assign_resource(struct pci_dev *dev, int resno) resource_size_t align, size; int ret; + res->flags |= IORESOURCE_UNSET; align = pci_resource_alignment(dev, res); if (!align) { dev_info(&dev->dev, "BAR %d: can't assign %pR " @@ -282,6 +283,7 @@ int pci_assign_resource(struct pci_dev *dev, int resno) ret = pci_revert_fw_address(res, dev, resno, size); if (!ret) { + res->flags &= ~IORESOURCE_UNSET; res->flags &= ~IORESOURCE_STARTALIGN; dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res); if (resno < PCI_BRIDGE_RESOURCES) @@ -297,6 +299,7 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz resource_size_t new_size; int ret; + res->flags |= IORESOURCE_UNSET; if (!res->parent) { dev_info(&dev->dev, "BAR %d: can't reassign an unassigned resource %pR " "\n", resno, res); @@ -307,6 +310,7 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz new_size = resource_size(res) + addsize; ret = _pci_assign_resource(dev, resno, new_size, min_align); if (!ret) { + res->flags &= ~IORESOURCE_UNSET; res->flags &= ~IORESOURCE_STARTALIGN; dev_info(&dev->dev, "BAR %d: reassigned %pR\n", resno, res); if (resno < PCI_BRIDGE_RESOURCES) -- cgit v1.2.3-70-g09d2 From 8a9d56097c142d0716234eb1cf7c8150c6dc1588 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 26 Feb 2014 11:26:00 -0700 Subject: PCI: Add "weak" generic pcibios_enable_device() implementation Many architectures implement pcibios_enable_device() the same way, so provide a default implementation in the core. Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index dc9ce62be7a..c3ce3d61091 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1185,6 +1185,11 @@ int pci_load_and_free_saved_state(struct pci_dev *dev, } EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state); +int __weak pcibios_enable_device(struct pci_dev *dev, int bars) +{ + return pci_enable_resources(dev, bars); +} + static int do_pci_enable_device(struct pci_dev *dev, int bars) { int err; -- cgit v1.2.3-70-g09d2