From 9410e0185e65394c0c6d046033904b53b97a9423 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Thu, 25 Sep 2014 16:39:18 +1000 Subject: [PATCH] powerpc/iommu/ddw: Fix endianness rtas_call() accepts and returns values in CPU endianness. The ddw_query_response and ddw_create_response structs members are defined and treated as BE but as they are passed to rtas_call() as (u32 *) and they get byteswapped automatically, the data is CPU-endian. This fixes ddw_query_response and ddw_create_response definitions and use. of_read_number() is designed to work with device tree cells - it assumes the input is big-endian and returns data in CPU-endian. However due to the ddw_create_response struct fix, create.addr_hi/lo are already CPU-endian so do not byteswap them. ddw_avail is a pointer to the "ibm,ddw-applicable" property which contains 3 cells which are big-endian as it is a device tree. rtas_call() accepts a RTAS token in CPU-endian. This makes use of of_property_read_u32_array to byte swap and avoid the need for a number of be32_to_cpu calls. Cc: stable@vger.kernel.org # v3.13+ Cc: Benjamin Herrenschmidt [aik: folded Anton's patch with of_property_read_u32_array] Signed-off-by: Alexey Kardashevskiy Acked-by: Anton Blanchard Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/pseries/iommu.c | 51 +++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 23 deletions(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 4642d6a..de1ec54 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -329,16 +329,16 @@ struct direct_window { /* Dynamic DMA Window support */ struct ddw_query_response { - __be32 windows_available; - __be32 largest_available_block; - __be32 page_size; - __be32 migration_capable; + u32 windows_available; + u32 largest_available_block; + u32 page_size; + u32 migration_capable; }; struct ddw_create_response { - __be32 liobn; - __be32 addr_hi; - __be32 addr_lo; + u32 liobn; + u32 addr_hi; + u32 addr_lo; }; static LIST_HEAD(direct_window_list); @@ -725,16 +725,18 @@ static void remove_ddw(struct device_node *np, bool remove_prop) { struct dynamic_dma_window_prop *dwp; struct property *win64; - const u32 *ddw_avail; + u32 ddw_avail[3]; u64 liobn; - int len, ret = 0; + int ret = 0; + + ret = of_property_read_u32_array(np, "ibm,ddw-applicable", + &ddw_avail[0], 3); - ddw_avail = of_get_property(np, "ibm,ddw-applicable", &len); win64 = of_find_property(np, DIRECT64_PROPNAME, NULL); if (!win64) return; - if (!ddw_avail || len < 3 * sizeof(u32) || win64->length < sizeof(*dwp)) + if (ret || win64->length < sizeof(*dwp)) goto delprop; dwp = win64->value; @@ -872,8 +874,9 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail, do { /* extra outputs are LIOBN and dma-addr (hi, lo) */ - ret = rtas_call(ddw_avail[1], 5, 4, (u32 *)create, cfg_addr, - BUID_HI(buid), BUID_LO(buid), page_shift, window_shift); + ret = rtas_call(ddw_avail[1], 5, 4, (u32 *)create, + cfg_addr, BUID_HI(buid), BUID_LO(buid), + page_shift, window_shift); } while (rtas_busy_delay(ret)); dev_info(&dev->dev, "ibm,create-pe-dma-window(%x) %x %x %x %x %x returned %d " @@ -910,7 +913,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) int page_shift; u64 dma_addr, max_addr; struct device_node *dn; - const u32 *uninitialized_var(ddw_avail); + u32 ddw_avail[3]; struct direct_window *window; struct property *win64; struct dynamic_dma_window_prop *ddwprop; @@ -942,8 +945,9 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) * for the given node in that order. * the property is actually in the parent, not the PE */ - ddw_avail = of_get_property(pdn, "ibm,ddw-applicable", &len); - if (!ddw_avail || len < 3 * sizeof(u32)) + ret = of_property_read_u32_array(pdn, "ibm,ddw-applicable", + &ddw_avail[0], 3); + if (ret) goto out_failed; /* @@ -966,11 +970,11 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) dev_dbg(&dev->dev, "no free dynamic windows"); goto out_failed; } - if (be32_to_cpu(query.page_size) & 4) { + if (query.page_size & 4) { page_shift = 24; /* 16MB */ - } else if (be32_to_cpu(query.page_size) & 2) { + } else if (query.page_size & 2) { page_shift = 16; /* 64kB */ - } else if (be32_to_cpu(query.page_size) & 1) { + } else if (query.page_size & 1) { page_shift = 12; /* 4kB */ } else { dev_dbg(&dev->dev, "no supported direct page size in mask %x", @@ -980,7 +984,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) /* verify the window * number of ptes will map the partition */ /* check largest block * page size > max memory hotplug addr */ max_addr = memory_hotplug_max(); - if (be32_to_cpu(query.largest_available_block) < (max_addr >> page_shift)) { + if (query.largest_available_block < (max_addr >> page_shift)) { dev_dbg(&dev->dev, "can't map partiton max 0x%llx with %u " "%llu-sized pages\n", max_addr, query.largest_available_block, 1ULL << page_shift); @@ -1006,8 +1010,9 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) if (ret != 0) goto out_free_prop; - ddwprop->liobn = create.liobn; - ddwprop->dma_base = cpu_to_be64(of_read_number(&create.addr_hi, 2)); + ddwprop->liobn = cpu_to_be32(create.liobn); + ddwprop->dma_base = cpu_to_be64(((u64)create.addr_hi << 32) | + create.addr_lo); ddwprop->tce_shift = cpu_to_be32(page_shift); ddwprop->window_shift = cpu_to_be32(len); @@ -1039,7 +1044,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) list_add(&window->list, &direct_window_list); spin_unlock(&direct_window_list_lock); - dma_addr = of_read_number(&create.addr_hi, 2); + dma_addr = be64_to_cpu(ddwprop->dma_base); goto out_unlock; out_free_window: -- 2.7.4