[PATCH v4 04/14] swiotlb: Refactor swiotlb_late_init_with_tbl

Claire Chang
2021-02-09T06:25:48Z

Refactor swiotlb_late_init_with_tbl to make the code reusable for
restricted DMA pool initialization.

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 65 ++++++++++++++++++++++++++++----------------
1 file changed, 42 insertions(+), 23 deletions(-)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 28b7bfe7a2a8..dc37951c6924 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -353,20 +353,21 @@ static void swiotlb_cleanup(void)
max_segment = 0;
}

-int
-swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
+static int swiotlb_init_tlb_pool(struct swiotlb *swiotlb, phys_addr_t start,
+ size_t size)
{
- struct swiotlb *swiotlb = &default_swiotlb;
- unsigned long i, bytes;
+ unsigned long i;
+ void *vaddr = phys_to_virt(start);

- bytes = nslabs << IO_TLB_SHIFT;
+ size = ALIGN(size, 1 << IO_TLB_SHIFT);
+ swiotlb->nslabs = size >> IO_TLB_SHIFT;
+ swiotlb->nslabs = ALIGN(swiotlb->nslabs, IO_TLB_SEGSIZE);

- swiotlb->nslabs = nslabs;
- swiotlb->start = virt_to_phys(tlb);
- swiotlb->end = swiotlb->start + bytes;
+ swiotlb->start = start;
+ swiotlb->end = swiotlb->start + size;

- set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
- memset(tlb, 0, bytes);
+ set_memory_decrypted((unsigned long)vaddr, size >> PAGE_SHIFT);
+ memset(vaddr, 0, size);

/*
* Allocate and initialize the free list array. This array is used
@@ -390,13 +391,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
swiotlb->orig_addr[i] = INVALID_PHYS_ADDR;
}
swiotlb->index = 0;
- no_iotlb_memory = false;
-
- swiotlb_print_info();

- late_alloc = 1;
-
- swiotlb_set_max_segment(swiotlb->nslabs << IO_TLB_SHIFT);
spin_lock_init(&swiotlb->lock);

return 0;
@@ -410,6 +405,27 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
return -ENOMEM;
}

+int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
+{
+ struct swiotlb *swiotlb = &default_swiotlb;
+ unsigned long bytes = nslabs << IO_TLB_SHIFT;
+ int ret;
+
+ ret = swiotlb_init_tlb_pool(swiotlb, virt_to_phys(tlb), bytes);
+ if (ret)
+ return ret;
+
+ no_iotlb_memory = false;
+
+ swiotlb_print_info();
+
+ late_alloc = 1;
+
+ swiotlb_set_max_segment(bytes);
+
+ return 0;
+}
+
void __init swiotlb_exit(void)
{
struct swiotlb *swiotlb = &default_swiotlb;
@@ -747,17 +763,20 @@ phys_addr_t get_swiotlb_start(void)
}

#ifdef CONFIG_DEBUG_FS
-
-static int __init swiotlb_create_debugfs(void)
+static void swiotlb_create_debugfs(struct swiotlb *swiotlb, const char *name,
+ struct dentry *node)
{
- struct swiotlb *swiotlb = &default_swiotlb;
-
- swiotlb->debugfs = debugfs_create_dir("swiotlb", NULL);
+ swiotlb->debugfs = debugfs_create_dir(name, node);
debugfs_create_ulong("io_tlb_nslabs", 0400, swiotlb->debugfs, &swiotlb->nslabs);
debugfs_create_ulong("io_tlb_used", 0400, swiotlb->debugfs, &swiotlb->used);
- return 0;
}

-late_initcall(swiotlb_create_debugfs);
+static int __init swiotlb_create_default_debugfs(void)
+{
+ swiotlb_create_debugfs(&default_swiotlb, "swiotlb", NULL);
+
+ return 0;
+}

+late_initcall(swiotlb_create_default_debugfs);
#endif
--
2.30.0.478.g8a0d178c01-goog