/* SPDX-License-Identifier: GPL-2.0 */ /* * Author(s)......: Holger Smolinski * Martin Schwidefsky * Bugreports.to..: * Copyright IBM Corp. 2000 * * History of changes * 07/24/00 new file * 05/04/02 code restructuring. */ #ifndef _S390_IDALS_H #define _S390_IDALS_H #include #include #include #include #include #include #include #define IDA_SIZE_SHIFT 12 #define IDA_BLOCK_SIZE (1UL << IDA_SIZE_SHIFT) #define IDA_2K_SIZE_SHIFT 11 #define IDA_2K_BLOCK_SIZE (1UL << IDA_2K_SIZE_SHIFT) /* * Test if an address/length pair needs an idal list. */ static inline bool idal_is_needed(void *vaddr, unsigned int length) { dma64_t paddr = virt_to_dma64(vaddr); return (((__force unsigned long)(paddr) + length - 1) >> 31) != 0; } /* * Return the number of idal words needed for an address/length pair. */ static inline unsigned int idal_nr_words(void *vaddr, unsigned int length) { unsigned int cidaw; cidaw = (unsigned long)vaddr & (IDA_BLOCK_SIZE - 1); cidaw += length + IDA_BLOCK_SIZE - 1; cidaw >>= IDA_SIZE_SHIFT; return cidaw; } /* * Return the number of 2K IDA words needed for an address/length pair. */ static inline unsigned int idal_2k_nr_words(void *vaddr, unsigned int length) { unsigned int cidaw; cidaw = (unsigned long)vaddr & (IDA_2K_BLOCK_SIZE - 1); cidaw += length + IDA_2K_BLOCK_SIZE - 1; cidaw >>= IDA_2K_SIZE_SHIFT; return cidaw; } /* * Create the list of idal words for an address/length pair. */ static inline dma64_t *idal_create_words(dma64_t *idaws, void *vaddr, unsigned int length) { dma64_t paddr = virt_to_dma64(vaddr); unsigned int cidaw; *idaws++ = paddr; cidaw = idal_nr_words(vaddr, length); paddr = dma64_and(paddr, -IDA_BLOCK_SIZE); while (--cidaw > 0) { paddr = dma64_add(paddr, IDA_BLOCK_SIZE); *idaws++ = paddr; } return idaws; } /* * Sets the address of the data in CCW. * If necessary it allocates an IDAL and sets the appropriate flags. */ static inline int set_normalized_cda(struct ccw1 *ccw, void *vaddr) { unsigned int nridaws; dma64_t *idal; if (ccw->flags & CCW_FLAG_IDA) return -EINVAL; nridaws = idal_nr_words(vaddr, ccw->count); if (nridaws > 0) { idal = kcalloc(nridaws, sizeof(*idal), GFP_ATOMIC | GFP_DMA); if (!idal) return -ENOMEM; idal_create_words(idal, vaddr, ccw->count); ccw->flags |= CCW_FLAG_IDA; vaddr = idal; } ccw->cda = virt_to_dma32(vaddr); return 0; } /* * Releases any allocated IDAL related to the CCW. */ static inline void clear_normalized_cda(struct ccw1 *ccw) { if (ccw->flags & CCW_FLAG_IDA) { kfree(dma32_to_virt(ccw->cda)); ccw->flags &= ~CCW_FLAG_IDA; } ccw->cda = 0; } /* * Idal buffer extension */ struct idal_buffer { size_t size; size_t page_order; dma64_t data[]; }; /* * Allocate an idal buffer */ static inline struct idal_buffer *idal_buffer_alloc(size_t size, int page_order) { int nr_chunks, nr_ptrs, i; struct idal_buffer *ib; void *vaddr; nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_SHIFT; nr_chunks = (PAGE_SIZE << page_order) >> IDA_SIZE_SHIFT; ib = kmalloc(struct_size(ib, data, nr_ptrs), GFP_DMA | GFP_KERNEL); if (!ib) return ERR_PTR(-ENOMEM); ib->size = size; ib->page_order = page_order; for (i = 0; i < nr_ptrs; i++) { if (i & (nr_chunks - 1)) { ib->data[i] = dma64_add(ib->data[i - 1], IDA_BLOCK_SIZE); continue; } vaddr = (void *)__get_free_pages(GFP_KERNEL, page_order); if (!vaddr) goto error; ib->data[i] = virt_to_dma64(vaddr); } return ib; error: while (i >= nr_chunks) { i -= nr_chunks; vaddr = dma64_to_virt(ib->data[i]); free_pages((unsigned long)vaddr, ib->page_order); } kfree(ib); return ERR_PTR(-ENOMEM); } /* * Free an idal buffer. */ static inline void idal_buffer_free(struct idal_buffer *ib) { int nr_chunks, nr_ptrs, i; void *vaddr; nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_SHIFT; nr_chunks = (PAGE_SIZE << ib->page_order) >> IDA_SIZE_SHIFT; for (i = 0; i < nr_ptrs; i += nr_chunks) { vaddr = dma64_to_virt(ib->data[i]); free_pages((unsigned long)vaddr, ib->page_order); } kfree(ib); } /* * Test if a idal list is really needed. */ static inline bool __idal_buffer_is_needed(struct idal_buffer *ib) { if (ib->size > (PAGE_SIZE << ib->page_order)) return true; return idal_is_needed(dma64_to_virt(ib->data[0]), ib->size); } /* * Set channel data address to idal buffer. */ static inline void idal_buffer_set_cda(struct idal_buffer *ib, struct ccw1 *ccw) { void *vaddr; if (__idal_buffer_is_needed(ib)) { /* Setup idals */ ccw->cda = virt_to_dma32(ib->data); ccw->flags |= CCW_FLAG_IDA; } else { /* * No idals needed - use direct addressing. Convert from * dma64_t to virt and then to dma32_t only because of type * checking. The physical address is known to be below 2GB. */ vaddr = dma64_to_virt(ib->data[0]); ccw->cda = virt_to_dma32(vaddr); } ccw->count = ib->size; } /* * Copy count bytes from an idal buffer to user memory */ static inline size_t idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count) { size_t left; void *vaddr; int i; BUG_ON(count > ib->size); for (i = 0; count > IDA_BLOCK_SIZE; i++) { vaddr = dma64_to_virt(ib->data[i]); left = copy_to_user(to, vaddr, IDA_BLOCK_SIZE); if (left) return left + count - IDA_BLOCK_SIZE; to = (void __user *)to + IDA_BLOCK_SIZE; count -= IDA_BLOCK_SIZE; } vaddr = dma64_to_virt(ib->data[i]); return copy_to_user(to, vaddr, count); } /* * Copy count bytes from user memory to an idal buffer */ static inline size_t idal_buffer_from_user(struct idal_buffer *ib, const void __user *from, size_t count) { size_t left; void *vaddr; int i; BUG_ON(count > ib->size); for (i = 0; count > IDA_BLOCK_SIZE; i++) { vaddr = dma64_to_virt(ib->data[i]); left = copy_from_user(vaddr, from, IDA_BLOCK_SIZE); if (left) return left + count - IDA_BLOCK_SIZE; from = (void __user *)from + IDA_BLOCK_SIZE; count -= IDA_BLOCK_SIZE; } vaddr = dma64_to_virt(ib->data[i]); return copy_from_user(vaddr, from, count); } #endif