Re: [PATCH v7 01/15] swiotlb: Refactor swiotlb init functions
From: Florian Fainelli <f.fainelli@gmail.com>
Date: 2021-05-19 18:50:17
Also in:
dri-devel, intel-gfx, linux-devicetree, linux-iommu, linux-pci, lkml, xen-devel
On 5/17/2021 11:42 PM, Claire Chang wrote:
quoted hunk ↗ jump to hunk
Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct initialization to make the code reusable. Note that we now also call set_memory_decrypted in swiotlb_init_with_tbl. Signed-off-by: Claire Chang <redacted> --- kernel/dma/swiotlb.c | 51 ++++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 26 deletions(-)diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 8ca7d505d61c..d3232fc19385 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c@@ -168,9 +168,30 @@ void __init swiotlb_update_mem_attributes(void) memset(vaddr, 0, bytes); } -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, + unsigned long nslabs, bool late_alloc) { + void *vaddr = phys_to_virt(start); unsigned long bytes = nslabs << IO_TLB_SHIFT, i; + + mem->nslabs = nslabs; + mem->start = start; + mem->end = mem->start + bytes; + mem->index = 0; + mem->late_alloc = late_alloc; + spin_lock_init(&mem->lock); + for (i = 0; i < mem->nslabs; i++) { + mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); + mem->slots[i].orig_addr = INVALID_PHYS_ADDR; + mem->slots[i].alloc_size = 0; + } + + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); + memset(vaddr, 0, bytes);
You are doing an unconditional set_memory_decrypted() followed by a memset here, and then:
quoted hunk ↗ jump to hunk
+} + +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +{ struct io_tlb_mem *mem; size_t alloc_size;@@ -186,16 +207,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) if (!mem) panic("%s: Failed to allocate %zu bytes align=0x%lx\n", __func__, alloc_size, PAGE_SIZE); - mem->nslabs = nslabs; - mem->start = __pa(tlb); - mem->end = mem->start + bytes; - mem->index = 0; - spin_lock_init(&mem->lock); - for (i = 0; i < mem->nslabs; i++) { - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); - mem->slots[i].orig_addr = INVALID_PHYS_ADDR; - mem->slots[i].alloc_size = 0; - } + + swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false);
You convert this call site with swiotlb_init_io_tlb_mem() which did not do the set_memory_decrypted()+memset(). Is this okay or should swiotlb_init_io_tlb_mem() add an additional argument to do this conditionally? -- Florian