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author | Christophe Leroy <christophe.leroy@c-s.fr> | 2019-08-20 17:07:17 +0300 |
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committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-08-27 06:03:35 +0300 |
commit | f381d5711f091facd8847a54a2377cc0d1519df2 (patch) | |
tree | c187a3aa9f280cafa727be14d92406682ba972a0 /arch/powerpc/mm/ioremap_64.c | |
parent | 7cd9b317b630683b0c8eb2dfcfb046003ad6b97b (diff) | |
download | linux-f381d5711f091facd8847a54a2377cc0d1519df2.tar.xz |
powerpc/mm: Move ioremap functions out of pgtable_32/64.c
Create ioremap_32.c and ioremap_64.c and move respective ioremap
functions out of pgtable_32.c and pgtable_64.c
In the meantime, fix a few comments and changes a printk() to
pr_warn(). Also fix a few oversplitted lines.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b5c8b02ccefd4ede64c61b53cf64fb5dacb35740.1566309263.git.christophe.leroy@c-s.fr
Diffstat (limited to 'arch/powerpc/mm/ioremap_64.c')
-rw-r--r-- | arch/powerpc/mm/ioremap_64.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/powerpc/mm/ioremap_64.c b/arch/powerpc/mm/ioremap_64.c new file mode 100644 index 000000000000..57f3b096143c --- /dev/null +++ b/arch/powerpc/mm/ioremap_64.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +int __weak ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size, + pgprot_t prot, int nid) +{ + unsigned long i; + + for (i = 0; i < size; i += PAGE_SIZE) { + int err = map_kernel_page(ea + i, pa + i, prot); + if (err) { + if (slab_is_available()) + unmap_kernel_range(ea, size); + else + WARN_ON_ONCE(1); /* Should clean up */ + return err; + } + } + + return 0; +} + +/** + * Low level function to establish the page tables for an IO mapping + */ +void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot) +{ + /* We don't support the 4K PFN hack with ioremap */ + if (pgprot_val(prot) & H_PAGE_4K_PFN) + return NULL; + + if ((ea + size) >= (void *)IOREMAP_END) { + pr_warn("Outside the supported range\n"); + return NULL; + } + + WARN_ON(pa & ~PAGE_MASK); + WARN_ON(((unsigned long)ea) & ~PAGE_MASK); + WARN_ON(size & ~PAGE_MASK); + + if (ioremap_range((unsigned long)ea, pa, size, prot, NUMA_NO_NODE)) + return NULL; + + return (void __iomem *)ea; +} +EXPORT_SYMBOL(__ioremap_at); + +/** + * Low level function to tear down the page tables for an IO mapping. This is + * used for mappings that are manipulated manually, like partial unmapping of + * PCI IOs or ISA space. + */ +void __iounmap_at(void *ea, unsigned long size) +{ + WARN_ON(((unsigned long)ea) & ~PAGE_MASK); + WARN_ON(size & ~PAGE_MASK); + + unmap_kernel_range((unsigned long)ea, size); +} +EXPORT_SYMBOL(__iounmap_at); + +void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size, + pgprot_t prot, void *caller) +{ + phys_addr_t paligned; + void __iomem *ret; + + /* + * Choose an address to map it to. Once the vmalloc system is running, + * we use it. Before that, we map using addresses going up from + * ioremap_bot. vmalloc will use the addresses from IOREMAP_BASE + * through ioremap_bot. + */ + paligned = addr & PAGE_MASK; + size = PAGE_ALIGN(addr + size) - paligned; + + if (size == 0 || paligned == 0) + return NULL; + + if (slab_is_available()) { + struct vm_struct *area; + + area = __get_vm_area_caller(size, VM_IOREMAP, ioremap_bot, + IOREMAP_END, caller); + if (area == NULL) + return NULL; + + area->phys_addr = paligned; + ret = __ioremap_at(paligned, area->addr, size, prot); + } else { + ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot); + if (ret) + ioremap_bot += size; + } + + if (ret) + ret += addr & ~PAGE_MASK; + return ret; +} + +/* + * Unmap an IO region and remove it from vmalloc'd list. + * Access to IO memory should be serialized by driver. + */ +void iounmap(volatile void __iomem *token) +{ + void *addr; + + if (!slab_is_available()) + return; + + addr = (void *)((unsigned long __force)PCI_FIX_ADDR(token) & PAGE_MASK); + + if ((unsigned long)addr < ioremap_bot) { + pr_warn("Attempt to iounmap early bolted mapping at 0x%p\n", addr); + return; + } + vunmap(addr); +} +EXPORT_SYMBOL(iounmap); |