swiotlb: simplify swiotlb_max_segment

Remove the bogus Xen override that was usually larger than the actual
size and just calculate the value on demand.  Note that
swiotlb_max_segment still doesn't make sense as an interface and should
eventually be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
This commit is contained in:
Christoph Hellwig 2022-02-14 11:44:42 +01:00
parent 3469d36d47
commit a2daa27c0c
3 changed files with 3 additions and 20 deletions

View File

@ -202,7 +202,6 @@ retry:
rc = swiotlb_late_init_with_tbl(start, nslabs);
if (rc)
return rc;
swiotlb_set_max_segment(PAGE_SIZE);
return 0;
error:
if (nslabs > 1024 && repeat--) {
@ -254,7 +253,6 @@ retry:
if (swiotlb_init_with_tbl(start, nslabs, true))
panic("Cannot allocate SWIOTLB buffer");
swiotlb_set_max_segment(PAGE_SIZE);
}
#endif /* CONFIG_X86 */

View File

@ -164,7 +164,6 @@ static inline void swiotlb_adjust_size(unsigned long size)
#endif /* CONFIG_SWIOTLB */
extern void swiotlb_print_info(void);
extern void swiotlb_set_max_segment(unsigned int);
#ifdef CONFIG_DMA_RESTRICTED_POOL
struct page *swiotlb_alloc(struct device *dev, size_t size);

View File

@ -68,12 +68,6 @@ struct io_tlb_mem io_tlb_default_mem;
phys_addr_t swiotlb_unencrypted_base;
/*
* Max segment that we can provide which (if pages are contingous) will
* not be bounced (unless SWIOTLB_FORCE is set).
*/
static unsigned int max_segment;
static unsigned long default_nslabs = IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIFT;
static int __init
@ -97,18 +91,12 @@ early_param("swiotlb", setup_io_tlb_npages);
unsigned int swiotlb_max_segment(void)
{
return io_tlb_default_mem.nslabs ? max_segment : 0;
if (!io_tlb_default_mem.nslabs)
return 0;
return rounddown(io_tlb_default_mem.nslabs << IO_TLB_SHIFT, PAGE_SIZE);
}
EXPORT_SYMBOL_GPL(swiotlb_max_segment);
void swiotlb_set_max_segment(unsigned int val)
{
if (swiotlb_force == SWIOTLB_FORCE)
max_segment = 1;
else
max_segment = rounddown(val, PAGE_SIZE);
}
unsigned long swiotlb_size_or_default(void)
{
return default_nslabs << IO_TLB_SHIFT;
@ -258,7 +246,6 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
if (verbose)
swiotlb_print_info();
swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);
return 0;
}
@ -359,7 +346,6 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true);
swiotlb_print_info();
swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);
return 0;
}