From 2d29960af0bee8cc6731b9bd3964850c9e7a6840 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 18 Mar 2021 17:14:23 +0100 Subject: [PATCH] swiotlb: dynamically allocate io_tlb_default_mem Instead of allocating ->list and ->orig_addr separately just do one dynamic allocation for the actual io_tlb_mem structure. This simplifies a lot of the initialization code, and also allows to just check io_tlb_default_mem to see if swiotlb is in use. Signed-off-by: Christoph Hellwig Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/swiotlb-xen.c | 22 +-- include/linux/swiotlb.h | 18 ++- kernel/dma/swiotlb.c | 304 ++++++++++++-------------------------- 3 files changed, 116 insertions(+), 228 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 5329ad54a5f3..4c89afc0df62 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -158,17 +158,14 @@ static const char *xen_swiotlb_error(enum xen_swiotlb_err err) int __ref xen_swiotlb_init(void) { enum xen_swiotlb_err m_ret = XEN_SWIOTLB_UNKNOWN; - unsigned long nslabs, bytes, order; - unsigned int repeat = 3; + unsigned long bytes = swiotlb_size_or_default(); + unsigned long nslabs = bytes >> IO_TLB_SHIFT; + unsigned int order, repeat = 3; int rc = -ENOMEM; char *start; - nslabs = swiotlb_nr_tbl(); - if (!nslabs) - nslabs = DEFAULT_NSLABS; retry: m_ret = XEN_SWIOTLB_ENOMEM; - bytes = nslabs << IO_TLB_SHIFT; order = get_order(bytes); /* @@ -221,19 +218,16 @@ error: #ifdef CONFIG_X86 void __init xen_swiotlb_init_early(void) { - unsigned long nslabs, bytes; + unsigned long bytes = swiotlb_size_or_default(); + unsigned long nslabs = bytes >> IO_TLB_SHIFT; unsigned int repeat = 3; char *start; int rc; - nslabs = swiotlb_nr_tbl(); - if (!nslabs) - nslabs = DEFAULT_NSLABS; retry: /* * Get IO TLB memory from any location. */ - bytes = nslabs << IO_TLB_SHIFT; start = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE); if (!start) panic("%s: Failed to allocate %lu bytes align=0x%lx\n", @@ -248,8 +242,8 @@ retry: if (repeat--) { /* Min is 2MB */ nslabs = max(1024UL, (nslabs >> 1)); - pr_info("Lowering to %luMB\n", - (nslabs << IO_TLB_SHIFT) >> 20); + bytes = nslabs << IO_TLB_SHIFT; + pr_info("Lowering to %luMB\n", bytes >> 20); goto retry; } panic("%s (rc:%d)", xen_swiotlb_error(XEN_SWIOTLB_EFIXUP), rc); @@ -548,7 +542,7 @@ xen_swiotlb_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, static int xen_swiotlb_dma_supported(struct device *hwdev, u64 mask) { - return xen_phys_to_dma(hwdev, io_tlb_default_mem.end - 1) <= mask; + return xen_phys_to_dma(hwdev, io_tlb_default_mem->end - 1) <= mask; } const struct dma_map_ops xen_swiotlb_dma_ops = { diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 5ec5378b17c3..63f7a63f61d0 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -90,28 +90,30 @@ struct io_tlb_mem { phys_addr_t end; unsigned long nslabs; unsigned long used; - unsigned int *list; unsigned int index; - phys_addr_t *orig_addr; - size_t *alloc_size; spinlock_t lock; struct dentry *debugfs; bool late_alloc; + struct io_tlb_slot { + phys_addr_t orig_addr; + size_t alloc_size; + unsigned int list; + } slots[]; }; -extern struct io_tlb_mem io_tlb_default_mem; +extern struct io_tlb_mem *io_tlb_default_mem; static inline bool is_swiotlb_buffer(phys_addr_t paddr) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; - return paddr >= mem->start && paddr < mem->end; + return mem && paddr >= mem->start && paddr < mem->end; } void __init swiotlb_exit(void); unsigned int swiotlb_max_segment(void); size_t swiotlb_max_mapping_size(struct device *dev); bool is_swiotlb_active(void); -void __init swiotlb_adjust_size(unsigned long new_size); +void __init swiotlb_adjust_size(unsigned long size); #else #define swiotlb_force SWIOTLB_NO_FORCE static inline bool is_swiotlb_buffer(phys_addr_t paddr) @@ -135,7 +137,7 @@ static inline bool is_swiotlb_active(void) return false; } -static inline void swiotlb_adjust_size(unsigned long new_size) +static inline void swiotlb_adjust_size(unsigned long size) { } #endif /* CONFIG_SWIOTLB */ diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index d9c097f0f78c..13de669a9b46 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -63,7 +63,7 @@ enum swiotlb_force swiotlb_force; -struct io_tlb_mem io_tlb_default_mem; +struct io_tlb_mem *io_tlb_default_mem; /* * Max segment that we can provide which (if pages are contingous) will @@ -71,15 +71,15 @@ struct io_tlb_mem io_tlb_default_mem; */ static unsigned int max_segment; +static unsigned long default_nslabs = IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIFT; + static int __init setup_io_tlb_npages(char *str) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - if (isdigit(*str)) { - mem->nslabs = simple_strtoul(str, &str, 0); /* avoid tail segment of size < IO_TLB_SEGSIZE */ - mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE); + default_nslabs = + ALIGN(simple_strtoul(str, &str, 0), IO_TLB_SEGSIZE); } if (*str == ',') ++str; @@ -87,24 +87,22 @@ setup_io_tlb_npages(char *str) swiotlb_force = SWIOTLB_FORCE; } else if (!strcmp(str, "noforce")) { swiotlb_force = SWIOTLB_NO_FORCE; - mem->nslabs = 1; + default_nslabs = 1; } return 0; } early_param("swiotlb", setup_io_tlb_npages); -static bool no_iotlb_memory; - unsigned long swiotlb_nr_tbl(void) { - return unlikely(no_iotlb_memory) ? 0 : io_tlb_default_mem.nslabs; + return io_tlb_default_mem ? io_tlb_default_mem->nslabs : 0; } EXPORT_SYMBOL_GPL(swiotlb_nr_tbl); unsigned int swiotlb_max_segment(void) { - return unlikely(no_iotlb_memory) ? 0 : max_segment; + return io_tlb_default_mem ? max_segment : 0; } EXPORT_SYMBOL_GPL(swiotlb_max_segment); @@ -118,44 +116,32 @@ void swiotlb_set_max_segment(unsigned int val) unsigned long swiotlb_size_or_default(void) { - unsigned long size; - - size = io_tlb_default_mem.nslabs << IO_TLB_SHIFT; - - return size ? size : (IO_TLB_DEFAULT_SIZE); + return default_nslabs << IO_TLB_SHIFT; } -void __init swiotlb_adjust_size(unsigned long new_size) +void __init swiotlb_adjust_size(unsigned long size) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long size; - /* * If swiotlb parameter has not been specified, give a chance to * architectures such as those supporting memory encryption to * adjust/expand SWIOTLB size for their use. */ - if (!mem->nslabs) { - size = ALIGN(new_size, IO_TLB_SIZE); - mem->nslabs = size >> IO_TLB_SHIFT; - mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE); - - pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20); - } + size = ALIGN(size, IO_TLB_SIZE); + default_nslabs = ALIGN(size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE); + pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20); } void swiotlb_print_info(void) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long bytes = mem->nslabs << IO_TLB_SHIFT; + struct io_tlb_mem *mem = io_tlb_default_mem; - if (no_iotlb_memory) { + if (!mem) { pr_warn("No low mem\n"); return; } pr_info("mapped [mem %pa-%pa] (%luMB)\n", &mem->start, &mem->end, - bytes >> 20); + (mem->nslabs << IO_TLB_SHIFT) >> 20); } static inline unsigned long io_tlb_offset(unsigned long val) @@ -176,13 +162,12 @@ static inline unsigned long nr_slots(u64 val) */ void __init swiotlb_update_mem_attributes(void) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; void *vaddr; unsigned long bytes; - if (no_iotlb_memory || mem->late_alloc) + if (!mem || mem->late_alloc) return; - vaddr = phys_to_virt(mem->start); bytes = PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT); set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); @@ -191,55 +176,33 @@ void __init swiotlb_update_mem_attributes(void) int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long i, bytes; + unsigned long bytes = nslabs << IO_TLB_SHIFT, i; + struct io_tlb_mem *mem; size_t alloc_size; /* protect against double initialization */ - if (WARN_ON_ONCE(mem->start)) + if (WARN_ON_ONCE(io_tlb_default_mem)) return -ENOMEM; - bytes = nslabs << IO_TLB_SHIFT; - + alloc_size = PAGE_ALIGN(struct_size(mem, slots, nslabs)); + mem = memblock_alloc(alloc_size, PAGE_SIZE); + 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); - - /* - * Allocate and initialize the free list array. This array is used - * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE - * between mem->start and mem->end. - */ - alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(int)); - mem->list = memblock_alloc(alloc_size, PAGE_SIZE); - if (!mem->list) - panic("%s: Failed to allocate %zu bytes align=0x%lx\n", - __func__, alloc_size, PAGE_SIZE); - - alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(phys_addr_t)); - mem->orig_addr = memblock_alloc(alloc_size, PAGE_SIZE); - if (!mem->orig_addr) - panic("%s: Failed to allocate %zu bytes align=0x%lx\n", - __func__, alloc_size, PAGE_SIZE); - - alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(size_t)); - mem->alloc_size = memblock_alloc(alloc_size, PAGE_SIZE); - if (mem->alloc_size) - panic("%s: Failed to allocate %zu bytes align=0x%lx\n", - __func__, alloc_size, PAGE_SIZE); - for (i = 0; i < mem->nslabs; i++) { - mem->list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i); - mem->orig_addr[i] = INVALID_PHYS_ADDR; - mem->alloc_size[i] = 0; + 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; } - no_iotlb_memory = false; + io_tlb_default_mem = mem; if (verbose) swiotlb_print_info(); - swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT); return 0; } @@ -251,30 +214,21 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) void __init swiotlb_init(int verbose) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - size_t default_size = IO_TLB_DEFAULT_SIZE; - unsigned char *vstart; - unsigned long bytes; - - if (!mem->nslabs) { - mem->nslabs = (default_size >> IO_TLB_SHIFT); - mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE); - } - - bytes = mem->nslabs << IO_TLB_SHIFT; + size_t bytes = PAGE_ALIGN(default_nslabs << IO_TLB_SHIFT); + void *tlb; /* Get IO TLB memory from the low pages */ - vstart = memblock_alloc_low(PAGE_ALIGN(bytes), PAGE_SIZE); - if (vstart && !swiotlb_init_with_tbl(vstart, mem->nslabs, verbose)) - return; + tlb = memblock_alloc_low(bytes, PAGE_SIZE); + if (!tlb) + goto fail; + if (swiotlb_init_with_tbl(tlb, default_nslabs, verbose)) + goto fail_free_mem; + return; - if (mem->start) { - memblock_free_early(mem->start, - PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT)); - mem->start = 0; - } +fail_free_mem: + memblock_free_early(__pa(tlb), bytes); +fail: pr_warn("Cannot allocate buffer"); - no_iotlb_memory = true; } /* @@ -285,23 +239,19 @@ swiotlb_init(int verbose) int swiotlb_late_init_with_default_size(size_t default_size) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long bytes, req_nslabs = mem->nslabs; + unsigned long nslabs = + ALIGN(default_size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE); + unsigned long bytes; unsigned char *vstart = NULL; unsigned int order; int rc = 0; - if (!mem->nslabs) { - mem->nslabs = (default_size >> IO_TLB_SHIFT); - mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE); - } - /* * Get IO TLB memory from the low pages */ - order = get_order(mem->nslabs << IO_TLB_SHIFT); - mem->nslabs = SLABS_PER_PAGE << order; - bytes = mem->nslabs << IO_TLB_SHIFT; + order = get_order(nslabs << IO_TLB_SHIFT); + nslabs = SLABS_PER_PAGE << order; + bytes = nslabs << IO_TLB_SHIFT; while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, @@ -311,43 +261,35 @@ swiotlb_late_init_with_default_size(size_t default_size) order--; } - if (!vstart) { - mem->nslabs = req_nslabs; + if (!vstart) return -ENOMEM; - } + if (order != get_order(bytes)) { pr_warn("only able to allocate %ld MB\n", (PAGE_SIZE << order) >> 20); - mem->nslabs = SLABS_PER_PAGE << order; + nslabs = SLABS_PER_PAGE << order; } - rc = swiotlb_late_init_with_tbl(vstart, mem->nslabs); + rc = swiotlb_late_init_with_tbl(vstart, nslabs); if (rc) free_pages((unsigned long)vstart, order); return rc; } -static void swiotlb_cleanup(void) -{ - struct io_tlb_mem *mem = &io_tlb_default_mem; - - mem->end = 0; - mem->start = 0; - mem->nslabs = 0; - max_segment = 0; -} - int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) { - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long i, bytes; + unsigned long bytes = nslabs << IO_TLB_SHIFT, i; + struct io_tlb_mem *mem; /* protect against double initialization */ - if (WARN_ON_ONCE(mem->start)) + if (WARN_ON_ONCE(io_tlb_default_mem)) return -ENOMEM; - bytes = nslabs << IO_TLB_SHIFT; + mem = (void *)__get_free_pages(GFP_KERNEL, + get_order(struct_size(mem, slots, nslabs))); + if (!mem) + return -ENOMEM; mem->nslabs = nslabs; mem->start = virt_to_phys(tlb); @@ -355,84 +297,35 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) mem->index = 0; mem->late_alloc = 1; 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)tlb, bytes >> PAGE_SHIFT); memset(tlb, 0, bytes); - /* - * Allocate and initialize the free list array. This array is used - * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE - * between mem->start and mem->end. - */ - mem->list = (unsigned int *)__get_free_pages(GFP_KERNEL, - get_order(mem->nslabs * sizeof(int))); - if (!mem->list) - goto cleanup3; - - mem->orig_addr = (phys_addr_t *) - __get_free_pages(GFP_KERNEL, - get_order(mem->nslabs * - sizeof(phys_addr_t))); - if (!mem->orig_addr) - goto cleanup4; - - mem->alloc_size = (size_t *) - __get_free_pages(GFP_KERNEL, - get_order(mem->nslabs * - sizeof(size_t))); - if (!mem->alloc_size) - goto cleanup5; - - for (i = 0; i < mem->nslabs; i++) { - mem->list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i); - mem->orig_addr[i] = INVALID_PHYS_ADDR; - mem->alloc_size[i] = 0; - } - no_iotlb_memory = false; - + io_tlb_default_mem = mem; swiotlb_print_info(); swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT); return 0; - -cleanup5: - free_pages((unsigned long)mem->orig_addr, - get_order(mem->nslabs * sizeof(phys_addr_t))); -cleanup4: - free_pages((unsigned long)mem->list, - get_order(mem->nslabs * sizeof(int))); - mem->list = NULL; -cleanup3: - swiotlb_cleanup(); - return -ENOMEM; } void __init swiotlb_exit(void) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; + size_t size; - if (!mem->orig_addr) + if (!mem) return; - if (mem->late_alloc) { - free_pages((unsigned long)mem->alloc_size, - get_order(mem->nslabs * sizeof(size_t))); - free_pages((unsigned long)mem->orig_addr, - get_order(mem->nslabs * sizeof(phys_addr_t))); - free_pages((unsigned long)mem->list, - get_order(mem->nslabs * sizeof(int))); - free_pages((unsigned long)phys_to_virt(mem->start), - get_order(mem->nslabs << IO_TLB_SHIFT)); - } else { - memblock_free_late(__pa(mem->alloc_size), - PAGE_ALIGN(mem->nslabs * sizeof(size_t))); - memblock_free_late(__pa(mem->orig_addr), - PAGE_ALIGN(mem->nslabs * sizeof(phys_addr_t))); - memblock_free_late(__pa(mem->list), - PAGE_ALIGN(mem->nslabs * sizeof(int))); - memblock_free_late(mem->start, - PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT)); - } - swiotlb_cleanup(); + size = struct_size(mem, slots, mem->nslabs); + if (mem->late_alloc) + free_pages((unsigned long)mem, get_order(size)); + else + memblock_free_late(__pa(mem), PAGE_ALIGN(size)); + io_tlb_default_mem = NULL; } /* @@ -441,10 +334,10 @@ void __init swiotlb_exit(void) static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size, enum dma_data_direction dir) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT; - phys_addr_t orig_addr = mem->orig_addr[index]; - size_t alloc_size = mem->alloc_size[index]; + phys_addr_t orig_addr = mem->slots[index].orig_addr; + size_t alloc_size = mem->slots[index].alloc_size; unsigned long pfn = PFN_DOWN(orig_addr); unsigned char *vaddr = phys_to_virt(tlb_addr); @@ -523,7 +416,7 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index) static int find_slots(struct device *dev, phys_addr_t orig_addr, size_t alloc_size) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; unsigned long boundary_mask = dma_get_seg_boundary(dev); dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(dev, mem->start) & boundary_mask; @@ -565,7 +458,7 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr, if (!iommu_is_span_boundary(index, nslots, nr_slots(tbl_dma_addr), max_slots)) { - if (mem->list[index] >= nslots) + if (mem->slots[index].list >= nslots) goto found; } index = wrap_index(mem, index + stride); @@ -577,11 +470,11 @@ not_found: found: for (i = index; i < index + nslots; i++) - mem->list[i] = 0; + mem->slots[i].list = 0; for (i = index - 1; io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && - mem->list[i]; i--) - mem->list[i] = ++count; + mem->slots[i].list; i--) + mem->slots[i].list = ++count; /* * Update the indices to avoid searching in the next round. @@ -600,12 +493,12 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, size_t mapping_size, size_t alloc_size, enum dma_data_direction dir, unsigned long attrs) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; unsigned int offset = swiotlb_align_offset(dev, orig_addr); unsigned int index, i; phys_addr_t tlb_addr; - if (no_iotlb_memory) + if (!mem) panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); if (mem_encrypt_active()) @@ -632,8 +525,9 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, * needed. */ for (i = 0; i < nr_slots(alloc_size + offset); i++) { - mem->orig_addr[index + i] = slot_addr(orig_addr, i); - mem->alloc_size[index + i] = alloc_size - (i << IO_TLB_SHIFT); + mem->slots[index + i].orig_addr = slot_addr(orig_addr, i); + mem->slots[index + i].alloc_size = + alloc_size - (i << IO_TLB_SHIFT); } tlb_addr = slot_addr(mem->start, index) + offset; if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && @@ -649,11 +543,11 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, size_t mapping_size, enum dma_data_direction dir, unsigned long attrs) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; unsigned long flags; unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr); int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT; - int nslots = nr_slots(mem->alloc_size[index] + offset); + int nslots = nr_slots(mem->slots[index].alloc_size + offset); int count, i; /* @@ -671,7 +565,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, */ spin_lock_irqsave(&mem->lock, flags); if (index + nslots < ALIGN(index + 1, IO_TLB_SEGSIZE)) - count = mem->list[index + nslots]; + count = mem->slots[index + nslots].list; else count = 0; @@ -680,9 +574,9 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, * superceeding slots */ for (i = index + nslots - 1; i >= index; i--) { - mem->list[i] = ++count; - mem->orig_addr[i] = INVALID_PHYS_ADDR; - mem->alloc_size[i] = 0; + mem->slots[i].list = ++count; + mem->slots[i].orig_addr = INVALID_PHYS_ADDR; + mem->slots[i].alloc_size = 0; } /* @@ -690,9 +584,9 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, * available (non zero) */ for (i = index - 1; - io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && mem->list[i]; + io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && mem->slots[i].list; i--) - mem->list[i] = ++count; + mem->slots[i].list = ++count; mem->used -= nslots; spin_unlock_irqrestore(&mem->lock, flags); } @@ -756,19 +650,17 @@ size_t swiotlb_max_mapping_size(struct device *dev) bool is_swiotlb_active(void) { - /* - * When SWIOTLB is initialized, even if mem->start points to physical - * address zero, mem->end surely doesn't. - */ - return io_tlb_default_mem.end != 0; + return io_tlb_default_mem != NULL; } #ifdef CONFIG_DEBUG_FS static int __init swiotlb_create_debugfs(void) { - struct io_tlb_mem *mem = &io_tlb_default_mem; + struct io_tlb_mem *mem = io_tlb_default_mem; + if (!mem) + return 0; mem->debugfs = debugfs_create_dir("swiotlb", NULL); debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs); debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);