1 files changed, 256 insertions, 0 deletions

diff --git a/arch/s390/include/asm/idals.h b/arch/s390/include/asm/idals.h
new file mode 100644
index 000000000000..e82c10efe65a
--- /dev/null
+++ b/arch/s390/include/asm/idals.h
@@ -0,0 +1,256 @@
+/* 
+ * 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/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