sh: Store Queue API rework.

Rewrite the store queue API for a per-cpu interface in the driver
model. The old miscdevice is dropped, due to TASK_SIZE limitations,
and no one was using it anyways.

Carve up and allocate store queue space with a bitmap, back sq
mapping objects with a slab cache, and let userspace worry about
its own prefetching.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 251 insertions, 314 deletions

diff --git a/arch/sh/kernel/cpu/sh4/sq.c b/arch/sh/kernel/cpu/sh4/sq.c
index b148966dd7c7..7bcc73f9b8df 100644
--- a/arch/sh/kernel/cpu/sh4/sq.c
+++ b/arch/sh/kernel/cpu/sh4/sq.c
@@ -1,50 +1,52 @@
 /*
- * arch/sh/kernel/cpu/sq.c
+ * arch/sh/kernel/cpu/sh4/sq.c
  *
  * General management API for SH-4 integrated Store Queues
  *
- * Copyright (C) 2001, 2002, 2003, 2004  Paul Mundt
+ * Copyright (C) 2001 - 2006  Paul Mundt
  * Copyright (C) 2001, 2002  M. R. Brown
  *
- * Some of this code has been adopted directly from the old arch/sh/mm/sq.c
- * hack that was part of the LinuxDC project. For all intents and purposes,
- * this is a completely new interface that really doesn't have much in common
- * with the old zone-based approach at all. In fact, it's only listed here for
- * general completeness.
- *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */
 #include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/bitmap.h>
+#include <linux/sysdev.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <linux/list.h>
-#include <linux/proc_fs.h>
-#include <linux/miscdevice.h>
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <asm/io.h>
 #include <asm/page.h>
 #include <asm/cacheflush.h>
-#include <asm/mmu_context.h>
 #include <asm/cpu/sq.h>
 
-static LIST_HEAD(sq_mapping_list);
+struct sq_mapping;
+
+struct sq_mapping {
+        const char *name;
+
+        unsigned long sq_addr;
+        unsigned long addr;
+        unsigned int size;
+
+        struct sq_mapping *next;
+};
+
+static struct sq_mapping *sq_mapping_list;
 static DEFINE_SPINLOCK(sq_mapping_lock);
+static kmem_cache_t *sq_cache;
+static unsigned long *sq_bitmap;
 
-/**
- * sq_flush - Flush (prefetch) the store queue cache
- * @addr: the store queue address to flush
- *
- * Executes a prefetch instruction on the specified store queue cache,
- * so that the cached data is written to physical memory.
- */
-inline void sq_flush(void *addr)
-{
-        __asm__ __volatile__ ("pref @%0" : : "r" (addr) : "memory");
-}
+#define store_queue_barrier()                   \
+do {                                            \
+        (void)ctrl_inl(P4SEG_STORE_QUE);        \
+        ctrl_outl(0, P4SEG_STORE_QUE + 0);      \
+        ctrl_outl(0, P4SEG_STORE_QUE + 8);      \
+} while (0);
 
 /**
  * sq_flush_range - Flush (prefetch) a specific SQ range
@@ -57,154 +59,73 @@ inline void sq_flush(void *addr)
 void sq_flush_range(unsigned long start, unsigned int len)
 {
         volatile unsigned long *sq = (unsigned long *)start;
-        unsigned long dummy;
 
         /* Flush the queues */
         for (len >>= 5; len--; sq += 8)
-                sq_flush((void *)sq);
+                prefetchw((void *)sq);
 
         /* Wait for completion */
-        dummy = ctrl_inl(P4SEG_STORE_QUE);
-
-        ctrl_outl(0, P4SEG_STORE_QUE + 0);
-        ctrl_outl(0, P4SEG_STORE_QUE + 8);
+        store_queue_barrier();
 }
 
-static struct sq_mapping *__sq_alloc_mapping(unsigned long virt, unsigned long phys, unsigned long size, const char *name)
+static inline void sq_mapping_list_add(struct sq_mapping *map)
 {
-        struct sq_mapping *map;
-
-        if (virt + size > SQ_ADDRMAX)
-                return ERR_PTR(-ENOSPC);
+        struct sq_mapping **p, *tmp;
 
-        map = kmalloc(sizeof(struct sq_mapping), GFP_KERNEL);
-        if (!map)
-                return ERR_PTR(-ENOMEM);
+        spin_lock_irq(&sq_mapping_lock);
 
-        INIT_LIST_HEAD(&map->list);
+        p = &sq_mapping_list;
+        while ((tmp = *p) != NULL)
+                p = &tmp->next;
 
-        map->sq_addr    = virt;
-        map->addr       = phys;
-        map->size       = size + 1;
-        map->name       = name;
+        map->next = tmp;
+        *p = map;
 
-        list_add(&map->list, &sq_mapping_list);
-
-        return map;
+        spin_unlock_irq(&sq_mapping_lock);
 }
 
-static unsigned long __sq_get_next_addr(void)
+static inline void sq_mapping_list_del(struct sq_mapping *map)
 {
-        if (!list_empty(&sq_mapping_list)) {
-                struct list_head *pos, *tmp;
-
-                /*
-                 * Read one off the list head, as it will have the highest
-                 * mapped allocation. Set the next one up right above it.
-                 *
-                 * This is somewhat sub-optimal, as we don't look at
-                 * gaps between allocations or anything lower then the
-                 * highest-level allocation.
-                 *
-                 * However, in the interest of performance and the general
-                 * lack of desire to do constant list rebalancing, we don't
-                 * worry about it.
-                 */
-                list_for_each_safe(pos, tmp, &sq_mapping_list) {
-                        struct sq_mapping *entry;
-
-                        entry = list_entry(pos, typeof(*entry), list);
-
-                        return entry->sq_addr + entry->size;
+        struct sq_mapping **p, *tmp;
+
+        spin_lock_irq(&sq_mapping_lock);
+
+        for (p = &sq_mapping_list; (tmp = *p); p = &tmp->next)
+                if (tmp == map) {
+                        *p = tmp->next;
+                        break;
                 }
-        }
 
-        return P4SEG_STORE_QUE;
+        spin_unlock_irq(&sq_mapping_lock);
 }
 
-/**
- * __sq_remap - Perform a translation from the SQ to a phys addr
- * @map: sq mapping containing phys and store queue addresses.
- *
- * Maps the store queue address specified in the mapping to the physical
- * address specified in the mapping.
- */
-static struct sq_mapping *__sq_remap(struct sq_mapping *map)
+static int __sq_remap(struct sq_mapping *map, unsigned long flags)
 {
-        unsigned long flags, pteh, ptel;
+#if defined(CONFIG_MMU)
         struct vm_struct *vma;
-        pgprot_t pgprot;
 
-        /*
-         * Without an MMU (or with it turned off), this is much more
-         * straightforward, as we can just load up each queue's QACR with
-         * the physical address appropriately masked.
-         */
-
-        ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR0);
-        ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR1);
-
-#ifdef CONFIG_MMU
-        /*
-         * With an MMU on the other hand, things are slightly more involved.
-         * Namely, we have to have a direct mapping between the SQ addr and
-         * the associated physical address in the UTLB by way of setting up
-         * a virt<->phys translation by hand. We do this by simply specifying
-         * the SQ addr in UTLB.VPN and the associated physical address in
-         * UTLB.PPN.
-         *
-         * Notably, even though this is a special case translation, and some
-         * of the configuration bits are meaningless, we're still required
-         * to have a valid ASID context in PTEH.
-         *
-         * We could also probably get by without explicitly setting PTEA, but
-         * we do it here just for good measure.
-         */
-        spin_lock_irqsave(&sq_mapping_lock, flags);
-
-        pteh = map->sq_addr;
-        ctrl_outl((pteh & MMU_VPN_MASK) | get_asid(), MMU_PTEH);
-
-        ptel = map->addr & PAGE_MASK;
-
-        if (cpu_data->flags & CPU_HAS_PTEA)
-                ctrl_outl(((ptel >> 28) & 0xe) | (ptel & 0x1), MMU_PTEA);
-
-        pgprot = pgprot_noncached(PAGE_KERNEL);
-
-        ptel &= _PAGE_FLAGS_HARDWARE_MASK;
-        ptel |= pgprot_val(pgprot);
-        ctrl_outl(ptel, MMU_PTEL);
-
-        __asm__ __volatile__ ("ldtlb" : : : "memory");
-
-        spin_unlock_irqrestore(&sq_mapping_lock, flags);
-
-        /*
-         * Next, we need to map ourselves in the kernel page table, so that
-         * future accesses after a TLB flush will be handled when we take a
-         * page fault.
-         *
-         * Theoretically we could just do this directly and not worry about
-         * setting up the translation by hand ahead of time, but for the
-         * cases where we want a one-shot SQ mapping followed by a quick
-         * writeout before we hit the TLB flush, we do it anyways. This way
-         * we at least save ourselves the initial page fault overhead.
-         */
         vma = __get_vm_area(map->size, VM_ALLOC, map->sq_addr, SQ_ADDRMAX);
         if (!vma)
-                return ERR_PTR(-ENOMEM);
+                return -ENOMEM;
 
         vma->phys_addr = map->addr;
 
         if (remap_area_pages((unsigned long)vma->addr, vma->phys_addr,
-                             map->size, pgprot_val(pgprot))) {
+                             map->size, flags)) {
                 vunmap(vma->addr);
-                return NULL;
+                return -EAGAIN;
         }
-#endif /* CONFIG_MMU */
+#else
+        /*
+         * Without an MMU (or with it turned off), this is much more
+         * straightforward, as we can just load up each queue's QACR with
+         * the physical address appropriately masked.
+         */
+        ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR0);
+        ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR1);
+#endif
 
-        return map;
+        return 0;
 }
 
 /**
@@ -212,42 +133,65 @@ static struct sq_mapping *__sq_remap(struct sq_mapping *map)
  * @phys: Physical address of mapping.
  * @size: Length of mapping.
  * @name: User invoking mapping.
+ * @flags: Protection flags.
  *
  * Remaps the physical address @phys through the next available store queue
  * address of @size length. @name is logged at boot time as well as through
- * the procfs interface.
- *
- * A pre-allocated and filled sq_mapping pointer is returned, and must be
- * cleaned up with a call to sq_unmap() when the user is done with the
- * mapping.
+ * the sysfs interface.
  */
-struct sq_mapping *sq_remap(unsigned long phys, unsigned int size, const char *name)
+unsigned long sq_remap(unsigned long phys, unsigned int size,
+                       const char *name, unsigned long flags)
 {
         struct sq_mapping *map;
-        unsigned long virt, end;
+        unsigned long end;
         unsigned int psz;
+        int ret, page;
 
         /* Don't allow wraparound or zero size */
         end = phys + size - 1;
-        if (!size || end < phys)
-                return NULL;
+        if (unlikely(!size || end < phys))
+                return -EINVAL;
         /* Don't allow anyone to remap normal memory.. */
-        if (phys < virt_to_phys(high_memory))
-                return NULL;
+        if (unlikely(phys < virt_to_phys(high_memory)))
+                return -EINVAL;
 
         phys &= PAGE_MASK;
+        size = PAGE_ALIGN(end + 1) - phys;
+
+        map = kmem_cache_alloc(sq_cache, GFP_KERNEL);
+        if (unlikely(!map))
+                return -ENOMEM;
+
+        map->addr = phys;
+        map->size = size;
+        map->name = name;
+
+        page = bitmap_find_free_region(sq_bitmap, 0x04000000,
+                                       get_order(map->size));
+        if (unlikely(page < 0)) {
+                ret = -ENOSPC;
+                goto out;
+        }
+
+        map->sq_addr = P4SEG_STORE_QUE + (page << PAGE_SHIFT);
+
+        ret = __sq_remap(map, flags);
+        if (unlikely(ret != 0))
+                goto out;
+
+        psz = (size + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+        pr_info("sqremap: %15s  [%4d page%s]  va 0x%08lx   pa 0x%08lx\n",
+                likely(map->name) ? map->name : "???",
+                psz, psz == 1 ? " " : "s",
+                map->sq_addr, map->addr);
 
-        size  = PAGE_ALIGN(end + 1) - phys;
-        virt  = __sq_get_next_addr();
-        psz   = (size + (PAGE_SIZE - 1)) / PAGE_SIZE;
-        map   = __sq_alloc_mapping(virt, phys, size, name);
+        sq_mapping_list_add(map);
 
-        printk("sqremap: %15s  [%4d page%s]  va 0x%08lx   pa 0x%08lx\n",
-               map->name ? map->name : "???",
-               psz, psz == 1 ? " " : "s",
-               map->sq_addr, map->addr);
+        return map->sq_addr;
 
-        return __sq_remap(map);
+out:
+        kmem_cache_free(sq_cache, map);
+        return ret;
 }
 
 /**
@@ -258,188 +202,198 @@ struct sq_mapping *sq_remap(unsigned long phys, unsigned int size, const char *n
  * sq_remap(). Also frees up the pte that was previously inserted into
  * the kernel page table and discards the UTLB translation.
  */
-void sq_unmap(struct sq_mapping *map)
+void sq_unmap(unsigned long vaddr)
 {
-        if (map->sq_addr > (unsigned long)high_memory)
-                vfree((void *)(map->sq_addr & PAGE_MASK));
+        struct sq_mapping **p, *map;
+        struct vm_struct *vma;
+        int page;
 
-        list_del(&map->list);
-        kfree(map);
-}
+        for (p = &sq_mapping_list; (map = *p); p = &map->next)
+                if (map->sq_addr == vaddr)
+                        break;
 
-/**
- * sq_clear - Clear a store queue range
- * @addr: Address to start clearing from.
- * @len: Length to clear.
- *
- * A quick zero-fill implementation for clearing out memory that has been
- * remapped through the store queues.
- */
-void sq_clear(unsigned long addr, unsigned int len)
-{
-        int i;
+        if (unlikely(!map)) {
+                printk("%s: bad store queue address 0x%08lx\n",
+                       __FUNCTION__, vaddr);
+                return;
+        }
 
-        /* Clear out both queues linearly */
-        for (i = 0; i < 8; i++) {
-                ctrl_outl(0, addr + i + 0);
-                ctrl_outl(0, addr + i + 8);
+        page = (map->sq_addr - P4SEG_STORE_QUE) >> PAGE_SHIFT;
+        bitmap_release_region(sq_bitmap, page, get_order(map->size));
+
+#ifdef CONFIG_MMU
+        vma = remove_vm_area((void *)(map->sq_addr & PAGE_MASK));
+        if (!vma) {
+                printk(KERN_ERR "%s: bad address 0x%08lx\n",
+                       __FUNCTION__, map->sq_addr);
+                return;
         }
+#endif
+
+        sq_mapping_list_del(map);
 
-        sq_flush_range(addr, len);
+        kmem_cache_free(sq_cache, map);
 }
 
-/**
- * sq_vma_unmap - Unmap a VMA range
- * @area: VMA containing range.
- * @addr: Start of range.
- * @len: Length of range.
+/*
+ * Needlessly complex sysfs interface. Unfortunately it doesn't seem like
+ * there is any other easy way to add things on a per-cpu basis without
+ * putting the directory entries somewhere stupid and having to create
+ * links in sysfs by hand back in to the per-cpu directories.
  *
- * Searches the sq_mapping_list for a mapping matching the sq addr @addr,
- * and subsequently frees up the entry. Further cleanup is done by generic
- * code.
+ * Some day we may want to have an additional abstraction per store
+ * queue, but considering the kobject hell we already have to deal with,
+ * it's simply not worth the trouble.
  */
-static void sq_vma_unmap(struct vm_area_struct *area,
-                         unsigned long addr, size_t len)
-{
-        struct list_head *pos, *tmp;
+static struct kobject *sq_kobject[NR_CPUS];
 
-        list_for_each_safe(pos, tmp, &sq_mapping_list) {
-                struct sq_mapping *entry;
+struct sq_sysfs_attr {
+        struct attribute attr;
+        ssize_t (*show)(char *buf);
+        ssize_t (*store)(const char *buf, size_t count);
+};
 
-                entry = list_entry(pos, typeof(*entry), list);
+#define to_sq_sysfs_attr(attr)  container_of(attr, struct sq_sysfs_attr, attr)
 
-                if (entry->sq_addr == addr) {
-                        /*
-                         * We could probably get away without doing the tlb flush
-                         * here, as generic code should take care of most of this
-                         * when unmapping the rest of the VMA range for us. Leave
-                         * it in for added sanity for the time being..
-                         */
-                        __flush_tlb_page(get_asid(), entry->sq_addr & PAGE_MASK);
+static ssize_t sq_sysfs_show(struct kobject *kobj, struct attribute *attr,
+                             char *buf)
+{
+        struct sq_sysfs_attr *sattr = to_sq_sysfs_attr(attr);
 
-                        list_del(&entry->list);
-                        kfree(entry);
+        if (likely(sattr->show))
+                return sattr->show(buf);
 
-                        return;
-                }
-        }
+        return -EIO;
 }
 
-/**
- * sq_vma_sync - Sync a VMA range
- * @area: VMA containing range.
- * @start: Start of range.
- * @len: Length of range.
- * @flags: Additional flags.
- *
- * Synchronizes an sq mapped range by flushing the store queue cache for
- * the duration of the mapping.
- *
- * Used internally for user mappings, which must use msync() to prefetch
- * the store queue cache.
- */
-static int sq_vma_sync(struct vm_area_struct *area,
-                       unsigned long start, size_t len, unsigned int flags)
+static ssize_t sq_sysfs_store(struct kobject *kobj, struct attribute *attr,
+                              const char *buf, size_t count)
 {
-        sq_flush_range(start, len);
+        struct sq_sysfs_attr *sattr = to_sq_sysfs_attr(attr);
 
-        return 0;
+        if (likely(sattr->store))
+                return sattr->store(buf, count);
+
+        return -EIO;
 }
 
-static struct vm_operations_struct sq_vma_ops = {
-        .unmap  = sq_vma_unmap,
-        .sync   = sq_vma_sync,
-};
+static ssize_t mapping_show(char *buf)
+{
+        struct sq_mapping **list, *entry;
+        char *p = buf;
 
-/**
- * sq_mmap - mmap() for /dev/cpu/sq
- * @file: unused.
- * @vma: VMA to remap.
- *
- * Remap the specified vma @vma through the store queues, and setup associated
- * information for the new mapping. Also build up the page tables for the new
- * area.
- */
-static int sq_mmap(struct file *file, struct vm_area_struct *vma)
+        for (list = &sq_mapping_list; (entry = *list); list = &entry->next)
+                p += sprintf(p, "%08lx-%08lx [%08lx]: %s\n",
+                             entry->sq_addr, entry->sq_addr + entry->size,
+                             entry->addr, entry->name);
+
+        return p - buf;
+}
+
+static ssize_t mapping_store(const char *buf, size_t count)
 {
-        unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
-        unsigned long size = vma->vm_end - vma->vm_start;
-        struct sq_mapping *map;
+        unsigned long base = 0, len = 0;
 
-        /*
-         * We're not interested in any arbitrary virtual address that has
-         * been stuck in the VMA, as we already know what addresses we
-         * want. Save off the size, and reposition the VMA to begin at
-         * the next available sq address.
-         */
-        vma->vm_start = __sq_get_next_addr();
-        vma->vm_end   = vma->vm_start + size;
+        sscanf(buf, "%lx %lx", &base, &len);
+        if (!base)
+                return -EIO;
 
-        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+        if (likely(len)) {
+                int ret = sq_remap(base, len, "Userspace",
+                                   pgprot_val(PAGE_SHARED));
+                if (ret < 0)
+                        return ret;
+        } else
+                sq_unmap(base);
 
-        vma->vm_flags |= VM_IO | VM_RESERVED;
+        return count;
+}
 
-        map = __sq_alloc_mapping(vma->vm_start, offset, size, "Userspace");
+static struct sq_sysfs_attr mapping_attr =
+        __ATTR(mapping, 0644, mapping_show, mapping_store);
 
-        if (io_remap_pfn_range(vma, map->sq_addr, map->addr >> PAGE_SHIFT,
-                                size, vma->vm_page_prot))
-                return -EAGAIN;
+static struct attribute *sq_sysfs_attrs[] = {
+        &mapping_attr.attr,
+        NULL,
+};
 
-        vma->vm_ops = &sq_vma_ops;
+static struct sysfs_ops sq_sysfs_ops = {
+        .show   = sq_sysfs_show,
+        .store  = sq_sysfs_store,
+};
 
-        return 0;
-}
+static struct kobj_type ktype_percpu_entry = {
+        .sysfs_ops      = &sq_sysfs_ops,
+        .default_attrs  = sq_sysfs_attrs,
+};
 
-#ifdef CONFIG_PROC_FS
-static int sq_mapping_read_proc(char *buf, char **start, off_t off,
-                                int len, int *eof, void *data)
+static int __devinit sq_sysdev_add(struct sys_device *sysdev)
 {
-        struct list_head *pos;
-        char *p = buf;
+        unsigned int cpu = sysdev->id;
+        struct kobject *kobj;
 
-        list_for_each_prev(pos, &sq_mapping_list) {
-                struct sq_mapping *entry;
+        sq_kobject[cpu] = kzalloc(sizeof(struct kobject), GFP_KERNEL);
+        if (unlikely(!sq_kobject[cpu]))
+                return -ENOMEM;
 
-                entry = list_entry(pos, typeof(*entry), list);
+        kobj = sq_kobject[cpu];
+        kobj->parent = &sysdev->kobj;
+        kobject_set_name(kobj, "%s", "sq");
+        kobj->ktype = &ktype_percpu_entry;
 
-                p += sprintf(p, "%08lx-%08lx [%08lx]: %s\n", entry->sq_addr,
-                             entry->sq_addr + entry->size - 1, entry->addr,
-                             entry->name);
-        }
-
-        return p - buf;
+        return kobject_register(kobj);
 }
-#endif
 
-static struct file_operations sq_fops = {
-        .owner          = THIS_MODULE,
-        .mmap           = sq_mmap,
-};
+static int __devexit sq_sysdev_remove(struct sys_device *sysdev)
+{
+        unsigned int cpu = sysdev->id;
+        struct kobject *kobj = sq_kobject[cpu];
 
-static struct miscdevice sq_dev = {
-        .minor          = STORE_QUEUE_MINOR,
-        .name           = "sq",
-        .fops           = &sq_fops,
+        kobject_unregister(kobj);
+        return 0;
+}
+
+static struct sysdev_driver sq_sysdev_driver = {
+        .add            = sq_sysdev_add,
+        .remove         = __devexit_p(sq_sysdev_remove),
 };
 
 static int __init sq_api_init(void)
 {
-        int ret;
+        unsigned int nr_pages = 0x04000000 >> PAGE_SHIFT;
+        unsigned int size = (nr_pages + (BITS_PER_LONG - 1)) / BITS_PER_LONG;
+        int ret = -ENOMEM;
+
         printk(KERN_NOTICE "sq: Registering store queue API.\n");
 
-        create_proc_read_entry("sq_mapping", 0, 0, sq_mapping_read_proc, 0);
+        sq_cache = kmem_cache_create("store_queue_cache",
+                                sizeof(struct sq_mapping), 0, 0,
+                                NULL, NULL);
+        if (unlikely(!sq_cache))
+                return ret;
 
-        ret = misc_register(&sq_dev);
-        if (ret)
-                remove_proc_entry("sq_mapping", NULL);
+        sq_bitmap = kzalloc(size, GFP_KERNEL);
+        if (unlikely(!sq_bitmap))
+                goto out;
+
+        ret = sysdev_driver_register(&cpu_sysdev_class, &sq_sysdev_driver);
+        if (unlikely(ret != 0))
+                goto out;
+
+        return 0;
+
+out:
+        kfree(sq_bitmap);
+        kmem_cache_destroy(sq_cache);
 
         return ret;
 }
 
 static void __exit sq_api_exit(void)
 {
-        misc_deregister(&sq_dev);
-        remove_proc_entry("sq_mapping", NULL);
+        sysdev_driver_unregister(&cpu_sysdev_class, &sq_sysdev_driver);
+        kfree(sq_bitmap);
+        kmem_cache_destroy(sq_cache);
 }
 
 module_init(sq_api_init);
@@ -448,11 +402,7 @@ module_exit(sq_api_exit);
 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, M. R. Brown <mrbrown@0xd6.org>");
 MODULE_DESCRIPTION("Simple API for SH-4 integrated Store Queues");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(STORE_QUEUE_MINOR);
 
 EXPORT_SYMBOL(sq_remap);
 EXPORT_SYMBOL(sq_unmap);
-EXPORT_SYMBOL(sq_clear);
-EXPORT_SYMBOL(sq_flush);
 EXPORT_SYMBOL(sq_flush_range);
-
diff --git a/include/asm-sh/cpu-sh4/sq.h b/include/asm-sh/cpu-sh4/sq.h
index 366b09166d3b..586d6491816a 100644
--- a/include/asm-sh/cpu-sh4/sq.h
+++ b/include/asm-sh/cpu-sh4/sq.h
@@ -17,7 +17,7 @@
  * Store queues range from e0000000-e3fffffc, allowing approx. 64MB to be
  * mapped to any physical address space. Since data is written (and aligned)
  * to 32-byte boundaries, we need to be sure that all allocations are aligned.
- */ 
+ */
 #define SQ_SIZE                 32
 #define SQ_ALIGN_MASK           (~(SQ_SIZE - 1))
 #define SQ_ALIGN(addr)          (((addr)+SQ_SIZE-1) & SQ_ALIGN_MASK)
@@ -26,23 +26,10 @@
 #define SQ_QACR1                (P4SEG_REG_BASE  + 0x3c)
 #define SQ_ADDRMAX              (P4SEG_STORE_QUE + 0x04000000)
 
-struct sq_mapping {
-        const char *name;
-
-        unsigned long sq_addr;
-        unsigned long addr;
-        unsigned int size;
-
-        struct list_head list;
-};
-
 /* arch/sh/kernel/cpu/sh4/sq.c */
-extern struct sq_mapping *sq_remap(unsigned long phys, unsigned int size, const char *name);
-extern void sq_unmap(struct sq_mapping *map);
-
-extern void sq_clear(unsigned long addr, unsigned int len);
-extern void sq_flush(void *addr);
-extern void sq_flush_range(unsigned long start, unsigned int len);
+unsigned long sq_remap(unsigned long phys, unsigned int size,
+                       const char *name, unsigned long flags);
+void sq_unmap(unsigned long vaddr);
+void sq_flush_range(unsigned long start, unsigned int len);
 
 #endif /* __ASM_CPU_SH4_SQ_H */
-