/* * File...........: linux/include/asm-s390x/idals.h * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com> * Martin Schwidefsky <schwidefsky@de.ibm.com> * Bugreports.to..: <Linux390@de.ibm.com> * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 2000a * History of changes * 07/24/00 new file * 05/04/02 code restructuring. */ #ifndef _S390_IDALS_H #define _S390_IDALS_H #include <linux/config.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/types.h> #include <linux/slab.h> #include <asm/cio.h> #include <asm/uaccess.h> #ifdef __s390x__ #define IDA_SIZE_LOG 12 /* 11 for 2k , 12 for 4k */ #else #define IDA_SIZE_LOG 11 /* 11 for 2k , 12 for 4k */ #endif #define IDA_BLOCK_SIZE (1L<<IDA_SIZE_LOG) /* * Test if an address/length pair needs an idal list. */ static inline int idal_is_needed(void *vaddr, unsigned int length) { #ifdef __s390x__ return ((__pa(vaddr) + length - 1) >> 31) != 0; #else return 0; #endif } /* * Return the number of idal words needed for an address/length pair. */ static inline unsigned int idal_nr_words(void *vaddr, unsigned int length) { #ifdef __s390x__ if (idal_is_needed(vaddr, length)) return ((__pa(vaddr) & (IDA_BLOCK_SIZE-1)) + length + (IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG; #endif return 0; } /* * Create the list of idal words for an address/length pair. */ static inline unsigned long * idal_create_words(unsigned long *idaws, void *vaddr, unsigned int length) { #ifdef __s390x__ unsigned long paddr; unsigned int cidaw; paddr = __pa(vaddr); cidaw = ((paddr & (IDA_BLOCK_SIZE-1)) + length + (IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG; *idaws++ = paddr; paddr &= -IDA_BLOCK_SIZE; while (--cidaw > 0) { paddr += IDA_BLOCK_SIZE; *idaws++ = paddr; } #endif 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) { #ifdef __s390x__ unsigned int nridaws; unsigned long *idal; if (ccw->flags & CCW_FLAG_IDA) return -EINVAL; nridaws = idal_nr_words(vaddr, ccw->count); if (nridaws > 0) { idal = kmalloc(nridaws * sizeof(unsigned long), GFP_ATOMIC | GFP_DMA ); if (idal == NULL) return -ENOMEM; idal_create_words(idal, vaddr, ccw->count); ccw->flags |= CCW_FLAG_IDA; vaddr = idal; } #endif ccw->cda = (__u32)(unsigned long) vaddr; return 0; } /* * Releases any allocated IDAL related to the CCW. */ static inline void clear_normalized_cda(struct ccw1 * ccw) { #ifdef __s390x__ if (ccw->flags & CCW_FLAG_IDA) { kfree((void *)(unsigned long) ccw->cda); ccw->flags &= ~CCW_FLAG_IDA; } #endif ccw->cda = 0; } /* * Idal buffer extension */ struct idal_buffer { size_t size; size_t page_order; void *data[0]; }; /* * Allocate an idal buffer */ static inline struct idal_buffer * idal_buffer_alloc(size_t size, int page_order) { struct idal_buffer *ib; int nr_chunks, nr_ptrs, i; nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG; nr_chunks = (4096 << page_order) >> IDA_SIZE_LOG; ib = kmalloc(sizeof(struct idal_buffer) + nr_ptrs*sizeof(void *), GFP_DMA | GFP_KERNEL); if (ib == NULL) return ERR_PTR(-ENOMEM); ib->size = size; ib->page_order = page_order; for (i = 0; i < nr_ptrs; i++) { if ((i & (nr_chunks - 1)) != 0) { ib->data[i] = ib->data[i-1] + IDA_BLOCK_SIZE; continue; } ib->data[i] = (void *) __get_free_pages(GFP_KERNEL, page_order); if (ib->data[i] != NULL) continue; // Not enough memory while (i >= nr_chunks) { i -= nr_chunks; free_pages((unsigned long) ib->data[i], ib->page_order); } kfree(ib); return ERR_PTR(-ENOMEM); } return ib; } /* * Free an idal buffer. */ static inline void idal_buffer_free(struct idal_buffer *ib) { int nr_chunks, nr_ptrs, i; nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG; nr_chunks = (4096 << ib->page_order) >> IDA_SIZE_LOG; for (i = 0; i < nr_ptrs; i += nr_chunks) free_pages((unsigned long) ib->data[i], ib->page_order); kfree(ib); } /* * Test if a idal list is really needed. */ static inline int __idal_buffer_is_needed(struct idal_buffer *ib) { #ifdef __s390x__ return ib->size > (4096ul << ib->page_order) || idal_is_needed(ib->data[0], ib->size); #else return ib->size > (4096ul << ib->page_order); #endif } /* * Set channel data address to idal buffer. */ static inline void idal_buffer_set_cda(struct idal_buffer *ib, struct ccw1 *ccw) { if (__idal_buffer_is_needed(ib)) { // setup idals; ccw->cda = (u32)(addr_t) ib->data; ccw->flags |= CCW_FLAG_IDA; } else // we do not need idals - use direct addressing ccw->cda = (u32)(addr_t) ib->data[0]; 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; int i; BUG_ON(count > ib->size); for (i = 0; count > IDA_BLOCK_SIZE; i++) { left = copy_to_user(to, ib->data[i], IDA_BLOCK_SIZE); if (left) return left + count - IDA_BLOCK_SIZE; to = (void __user *) to + IDA_BLOCK_SIZE; count -= IDA_BLOCK_SIZE; } return copy_to_user(to, ib->data[i], 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; int i; BUG_ON(count > ib->size); for (i = 0; count > IDA_BLOCK_SIZE; i++) { left = copy_from_user(ib->data[i], from, IDA_BLOCK_SIZE); if (left) return left + count - IDA_BLOCK_SIZE; from = (void __user *) from + IDA_BLOCK_SIZE; count -= IDA_BLOCK_SIZE; } return copy_from_user(ib->data[i], from, count); } #endif