+++ /dev/null
-/* drivers/android/pmem.c
- *
- * Copyright (C) 2007 Google, Inc.
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- */
-
-#include <linux/miscdevice.h>
-#include <linux/platform_device.h>
-#include <linux/fs.h>
-#include <linux/file.h>
-#include <linux/mm.h>
-#include <linux/list.h>
-#include <linux/debugfs.h>
-#include <linux/android_pmem.h>
-#include <linux/mempolicy.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/uaccess.h>
-#include <asm/cacheflush.h>
-
-#define PMEM_MAX_DEVICES 10
-#define PMEM_MAX_ORDER 128
-#define PMEM_MIN_ALLOC PAGE_SIZE
-
-#define PMEM_DEBUG 1
-
-/* indicates that a refernce to this file has been taken via get_pmem_file,
- * the file should not be released until put_pmem_file is called */
-#define PMEM_FLAGS_BUSY 0x1
-/* indicates that this is a suballocation of a larger master range */
-#define PMEM_FLAGS_CONNECTED (0x1 << 1)
-/* indicates this is a master and not a sub allocation and that it is mmaped */
-#define PMEM_FLAGS_MASTERMAP (0x1 << 2)
-/* submap and unsubmap flags indicate:
- * 00: subregion has never been mmaped
- * 10: subregion has been mmaped, reference to the mm was taken
- * 11: subretion has ben released, refernece to the mm still held
- * 01: subretion has been released, reference to the mm has been released
- */
-#define PMEM_FLAGS_SUBMAP (0x1 << 3)
-#define PMEM_FLAGS_UNSUBMAP (0x1 << 4)
-
-
-struct pmem_data {
- /* in alloc mode: an index into the bitmap
- * in no_alloc mode: the size of the allocation */
- int index;
- /* see flags above for descriptions */
- unsigned int flags;
- /* protects this data field, if the mm_mmap sem will be held at the
- * same time as this sem, the mm sem must be taken first (as this is
- * the order for vma_open and vma_close ops */
- struct rw_semaphore sem;
- /* info about the mmaping process */
- struct vm_area_struct *vma;
- /* task struct of the mapping process */
- struct task_struct *task;
- /* process id of teh mapping process */
- pid_t pid;
- /* file descriptor of the master */
- int master_fd;
- /* file struct of the master */
- struct file *master_file;
- /* a list of currently available regions if this is a suballocation */
- struct list_head region_list;
- /* a linked list of data so we can access them for debugging */
- struct list_head list;
-#if PMEM_DEBUG
- int ref;
-#endif
-};
-
-struct pmem_bits {
- unsigned allocated:1; /* 1 if allocated, 0 if free */
- unsigned order:7; /* size of the region in pmem space */
-};
-
-struct pmem_region_node {
- struct pmem_region region;
- struct list_head list;
-};
-
-#define PMEM_DEBUG_MSGS 0
-#if PMEM_DEBUG_MSGS
-#define DLOG(fmt, args...) \
- do { printk(KERN_INFO "[%s:%s:%d] "fmt, __FILE__, __func__, __LINE__, \
- ##args); } \
- while (0)
-#else
-#define DLOG(x...) do {} while (0)
-#endif
-
-struct pmem_info {
- struct miscdevice dev;
- /* physical start address of the remaped pmem space */
- unsigned long base;
- /* vitual start address of the remaped pmem space */
- unsigned char __iomem *vbase;
- /* total size of the pmem space */
- unsigned long size;
- /* number of entries in the pmem space */
- unsigned long num_entries;
- /* pfn of the garbage page in memory */
- unsigned long garbage_pfn;
- /* index of the garbage page in the pmem space */
- int garbage_index;
- /* the bitmap for the region indicating which entries are allocated
- * and which are free */
- struct pmem_bits *bitmap;
- /* indicates the region should not be managed with an allocator */
- unsigned no_allocator;
- /* indicates maps of this region should be cached, if a mix of
- * cached and uncached is desired, set this and open the device with
- * O_SYNC to get an uncached region */
- unsigned cached;
- unsigned buffered;
- /* in no_allocator mode the first mapper gets the whole space and sets
- * this flag */
- unsigned allocated;
- /* for debugging, creates a list of pmem file structs, the
- * data_list_sem should be taken before pmem_data->sem if both are
- * needed */
- struct semaphore data_list_sem;
- struct list_head data_list;
- /* pmem_sem protects the bitmap array
- * a write lock should be held when modifying entries in bitmap
- * a read lock should be held when reading data from bits or
- * dereferencing a pointer into bitmap
- *
- * pmem_data->sem protects the pmem data of a particular file
- * Many of the function that require the pmem_data->sem have a non-
- * locking version for when the caller is already holding that sem.
- *
- * IF YOU TAKE BOTH LOCKS TAKE THEM IN THIS ORDER:
- * down(pmem_data->sem) => down(bitmap_sem)
- */
- struct rw_semaphore bitmap_sem;
-
- long (*ioctl)(struct file *, unsigned int, unsigned long);
- int (*release)(struct inode *, struct file *);
-};
-
-static struct pmem_info pmem[PMEM_MAX_DEVICES];
-static int id_count;
-
-#define PMEM_IS_FREE(id, index) (!(pmem[id].bitmap[index].allocated))
-#define PMEM_ORDER(id, index) pmem[id].bitmap[index].order
-#define PMEM_BUDDY_INDEX(id, index) (index ^ (1 << PMEM_ORDER(id, index)))
-#define PMEM_NEXT_INDEX(id, index) (index + (1 << PMEM_ORDER(id, index)))
-#define PMEM_OFFSET(index) (index * PMEM_MIN_ALLOC)
-#define PMEM_START_ADDR(id, index) (PMEM_OFFSET(index) + pmem[id].base)
-#define PMEM_LEN(id, index) ((1 << PMEM_ORDER(id, index)) * PMEM_MIN_ALLOC)
-#define PMEM_END_ADDR(id, index) (PMEM_START_ADDR(id, index) + \
- PMEM_LEN(id, index))
-#define PMEM_START_VADDR(id, index) (PMEM_OFFSET(id, index) + pmem[id].vbase)
-#define PMEM_END_VADDR(id, index) (PMEM_START_VADDR(id, index) + \
- PMEM_LEN(id, index))
-#define PMEM_REVOKED(data) (data->flags & PMEM_FLAGS_REVOKED)
-#define PMEM_IS_PAGE_ALIGNED(addr) (!((addr) & (~PAGE_MASK)))
-#define PMEM_IS_SUBMAP(data) ((data->flags & PMEM_FLAGS_SUBMAP) && \
- (!(data->flags & PMEM_FLAGS_UNSUBMAP)))
-
-static int pmem_release(struct inode *, struct file *);
-static int pmem_mmap(struct file *, struct vm_area_struct *);
-static int pmem_open(struct inode *, struct file *);
-static long pmem_ioctl(struct file *, unsigned int, unsigned long);
-
-const struct file_operations pmem_fops = {
- .release = pmem_release,
- .mmap = pmem_mmap,
- .open = pmem_open,
- .unlocked_ioctl = pmem_ioctl,
-};
-
-static int get_id(struct file *file)
-{
- return MINOR(file->f_dentry->d_inode->i_rdev);
-}
-
-static int is_pmem_file(struct file *file)
-{
- int id;
-
- if (unlikely(!file || !file->f_dentry || !file->f_dentry->d_inode))
- return 0;
- id = get_id(file);
- if (unlikely(id >= PMEM_MAX_DEVICES))
- return 0;
- if (unlikely(file->f_dentry->d_inode->i_rdev !=
- MKDEV(MISC_MAJOR, pmem[id].dev.minor)))
- return 0;
- return 1;
-}
-
-static int has_allocation(struct file *file)
-{
- struct pmem_data *data;
- /* check is_pmem_file first if not accessed via pmem_file_ops */
-
- if (unlikely(!file->private_data))
- return 0;
- data = file->private_data;
- if (unlikely(data->index < 0))
- return 0;
- return 1;
-}
-
-static int is_master_owner(struct file *file)
-{
- struct file *master_file;
- struct pmem_data *data;
- int put_needed, ret = 0;
-
- if (!is_pmem_file(file) || !has_allocation(file))
- return 0;
- data = file->private_data;
- if (PMEM_FLAGS_MASTERMAP & data->flags)
- return 1;
- master_file = fget_light(data->master_fd, &put_needed);
- if (master_file && data->master_file == master_file)
- ret = 1;
- fput_light(master_file, put_needed);
- return ret;
-}
-
-static int pmem_free(int id, int index)
-{
- /* caller should hold the write lock on pmem_sem! */
- int buddy, curr = index;
- DLOG("index %d\n", index);
-
- if (pmem[id].no_allocator) {
- pmem[id].allocated = 0;
- return 0;
- }
- /* clean up the bitmap, merging any buddies */
- pmem[id].bitmap[curr].allocated = 0;
- /* find a slots buddy Buddy# = Slot# ^ (1 << order)
- * if the buddy is also free merge them
- * repeat until the buddy is not free or end of the bitmap is reached
- */
- do {
- buddy = PMEM_BUDDY_INDEX(id, curr);
- if (PMEM_IS_FREE(id, buddy) &&
- PMEM_ORDER(id, buddy) == PMEM_ORDER(id, curr)) {
- PMEM_ORDER(id, buddy)++;
- PMEM_ORDER(id, curr)++;
- curr = min(buddy, curr);
- } else {
- break;
- }
- } while (curr < pmem[id].num_entries);
-
- return 0;
-}
-
-static void pmem_revoke(struct file *file, struct pmem_data *data);
-
-static int pmem_release(struct inode *inode, struct file *file)
-{
- struct pmem_data *data = file->private_data;
- struct pmem_region_node *region_node;
- struct list_head *elt, *elt2;
- int id = get_id(file), ret = 0;
-
-
- down(&pmem[id].data_list_sem);
- /* if this file is a master, revoke all the memory in the connected
- * files */
- if (PMEM_FLAGS_MASTERMAP & data->flags) {
- struct pmem_data *sub_data;
- list_for_each(elt, &pmem[id].data_list) {
- sub_data = list_entry(elt, struct pmem_data, list);
- down_read(&sub_data->sem);
- if (PMEM_IS_SUBMAP(sub_data) &&
- file == sub_data->master_file) {
- up_read(&sub_data->sem);
- pmem_revoke(file, sub_data);
- } else
- up_read(&sub_data->sem);
- }
- }
- list_del(&data->list);
- up(&pmem[id].data_list_sem);
-
-
- down_write(&data->sem);
-
- /* if its not a conencted file and it has an allocation, free it */
- if (!(PMEM_FLAGS_CONNECTED & data->flags) && has_allocation(file)) {
- down_write(&pmem[id].bitmap_sem);
- ret = pmem_free(id, data->index);
- up_write(&pmem[id].bitmap_sem);
- }
-
- /* if this file is a submap (mapped, connected file), downref the
- * task struct */
- if (PMEM_FLAGS_SUBMAP & data->flags)
- if (data->task) {
- put_task_struct(data->task);
- data->task = NULL;
- }
-
- file->private_data = NULL;
-
- list_for_each_safe(elt, elt2, &data->region_list) {
- region_node = list_entry(elt, struct pmem_region_node, list);
- list_del(elt);
- kfree(region_node);
- }
- BUG_ON(!list_empty(&data->region_list));
-
- up_write(&data->sem);
- kfree(data);
- if (pmem[id].release)
- ret = pmem[id].release(inode, file);
-
- return ret;
-}
-
-static int pmem_open(struct inode *inode, struct file *file)
-{
- struct pmem_data *data;
- int id = get_id(file);
- int ret = 0;
-
- DLOG("current %u file %p(%d)\n", current->pid, file, file_count(file));
- /* setup file->private_data to indicate its unmapped */
- /* you can only open a pmem device one time */
- if (file->private_data != NULL)
- return -1;
- data = kmalloc(sizeof(struct pmem_data), GFP_KERNEL);
- if (!data) {
- printk("pmem: unable to allocate memory for pmem metadata.");
- return -1;
- }
- data->flags = 0;
- data->index = -1;
- data->task = NULL;
- data->vma = NULL;
- data->pid = 0;
- data->master_file = NULL;
-#if PMEM_DEBUG
- data->ref = 0;
-#endif
- INIT_LIST_HEAD(&data->region_list);
- init_rwsem(&data->sem);
-
- file->private_data = data;
- INIT_LIST_HEAD(&data->list);
-
- down(&pmem[id].data_list_sem);
- list_add(&data->list, &pmem[id].data_list);
- up(&pmem[id].data_list_sem);
- return ret;
-}
-
-static unsigned long pmem_order(unsigned long len)
-{
- int i;
-
- len = (len + PMEM_MIN_ALLOC - 1)/PMEM_MIN_ALLOC;
- len--;
- for (i = 0; i < sizeof(len)*8; i++)
- if (len >> i == 0)
- break;
- return i;
-}
-
-static int pmem_allocate(int id, unsigned long len)
-{
- /* caller should hold the write lock on pmem_sem! */
- /* return the corresponding pdata[] entry */
- int curr = 0;
- int end = pmem[id].num_entries;
- int best_fit = -1;
- unsigned long order = pmem_order(len);
-
- if (pmem[id].no_allocator) {
- DLOG("no allocator");
- if ((len > pmem[id].size) || pmem[id].allocated)
- return -1;
- pmem[id].allocated = 1;
- return len;
- }
-
- if (order > PMEM_MAX_ORDER)
- return -1;
- DLOG("order %lx\n", order);
-
- /* look through the bitmap:
- * if you find a free slot of the correct order use it
- * otherwise, use the best fit (smallest with size > order) slot
- */
- while (curr < end) {
- if (PMEM_IS_FREE(id, curr)) {
- if (PMEM_ORDER(id, curr) == (unsigned char)order) {
- /* set the not free bit and clear others */
- best_fit = curr;
- break;
- }
- if (PMEM_ORDER(id, curr) > (unsigned char)order &&
- (best_fit < 0 ||
- PMEM_ORDER(id, curr) < PMEM_ORDER(id, best_fit)))
- best_fit = curr;
- }
- curr = PMEM_NEXT_INDEX(id, curr);
- }
-
- /* if best_fit < 0, there are no suitable slots,
- * return an error
- */
- if (best_fit < 0) {
- printk("pmem: no space left to allocate!\n");
- return -1;
- }
-
- /* now partition the best fit:
- * split the slot into 2 buddies of order - 1
- * repeat until the slot is of the correct order
- */
- while (PMEM_ORDER(id, best_fit) > (unsigned char)order) {
- int buddy;
- PMEM_ORDER(id, best_fit) -= 1;
- buddy = PMEM_BUDDY_INDEX(id, best_fit);
- PMEM_ORDER(id, buddy) = PMEM_ORDER(id, best_fit);
- }
- pmem[id].bitmap[best_fit].allocated = 1;
- return best_fit;
-}
-
-static pgprot_t phys_mem_access_prot(struct file *file, pgprot_t vma_prot)
-{
- int id = get_id(file);
-#ifdef pgprot_noncached
- if (pmem[id].cached == 0 || file->f_flags & O_SYNC)
- return pgprot_noncached(vma_prot);
-#endif
-#ifdef pgprot_ext_buffered
- else if (pmem[id].buffered)
- return pgprot_ext_buffered(vma_prot);
-#endif
- return vma_prot;
-}
-
-static unsigned long pmem_start_addr(int id, struct pmem_data *data)
-{
- if (pmem[id].no_allocator)
- return PMEM_START_ADDR(id, 0);
- else
- return PMEM_START_ADDR(id, data->index);
-
-}
-
-static void *pmem_start_vaddr(int id, struct pmem_data *data)
-{
- return pmem_start_addr(id, data) - pmem[id].base + pmem[id].vbase;
-}
-
-static unsigned long pmem_len(int id, struct pmem_data *data)
-{
- if (pmem[id].no_allocator)
- return data->index;
- else
- return PMEM_LEN(id, data->index);
-}
-
-static int pmem_map_garbage(int id, struct vm_area_struct *vma,
- struct pmem_data *data, unsigned long offset,
- unsigned long len)
-{
- int i, garbage_pages = len >> PAGE_SHIFT;
-
- vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP | VM_SHARED | VM_WRITE;
- for (i = 0; i < garbage_pages; i++) {
- if (vm_insert_pfn(vma, vma->vm_start + offset + (i * PAGE_SIZE),
- pmem[id].garbage_pfn))
- return -EAGAIN;
- }
- return 0;
-}
-
-static int pmem_unmap_pfn_range(int id, struct vm_area_struct *vma,
- struct pmem_data *data, unsigned long offset,
- unsigned long len)
-{
- int garbage_pages;
- DLOG("unmap offset %lx len %lx\n", offset, len);
-
- BUG_ON(!PMEM_IS_PAGE_ALIGNED(len));
-
- garbage_pages = len >> PAGE_SHIFT;
- zap_page_range(vma, vma->vm_start + offset, len, NULL);
- pmem_map_garbage(id, vma, data, offset, len);
- return 0;
-}
-
-static int pmem_map_pfn_range(int id, struct vm_area_struct *vma,
- struct pmem_data *data, unsigned long offset,
- unsigned long len)
-{
- DLOG("map offset %lx len %lx\n", offset, len);
- BUG_ON(!PMEM_IS_PAGE_ALIGNED(vma->vm_start));
- BUG_ON(!PMEM_IS_PAGE_ALIGNED(vma->vm_end));
- BUG_ON(!PMEM_IS_PAGE_ALIGNED(len));
- BUG_ON(!PMEM_IS_PAGE_ALIGNED(offset));
-
- if (io_remap_pfn_range(vma, vma->vm_start + offset,
- (pmem_start_addr(id, data) + offset) >> PAGE_SHIFT,
- len, vma->vm_page_prot)) {
- return -EAGAIN;
- }
- return 0;
-}
-
-static int pmem_remap_pfn_range(int id, struct vm_area_struct *vma,
- struct pmem_data *data, unsigned long offset,
- unsigned long len)
-{
- /* hold the mm semp for the vma you are modifying when you call this */
- BUG_ON(!vma);
- zap_page_range(vma, vma->vm_start + offset, len, NULL);
- return pmem_map_pfn_range(id, vma, data, offset, len);
-}
-
-static void pmem_vma_open(struct vm_area_struct *vma)
-{
- struct file *file = vma->vm_file;
- struct pmem_data *data = file->private_data;
- int id = get_id(file);
- /* this should never be called as we don't support copying pmem
- * ranges via fork */
- BUG_ON(!has_allocation(file));
- down_write(&data->sem);
- /* remap the garbage pages, forkers don't get access to the data */
- pmem_unmap_pfn_range(id, vma, data, 0, vma->vm_start - vma->vm_end);
- up_write(&data->sem);
-}
-
-static void pmem_vma_close(struct vm_area_struct *vma)
-{
- struct file *file = vma->vm_file;
- struct pmem_data *data = file->private_data;
-
- DLOG("current %u ppid %u file %p count %d\n", current->pid,
- current->parent->pid, file, file_count(file));
- if (unlikely(!is_pmem_file(file) || !has_allocation(file))) {
- printk(KERN_WARNING "pmem: something is very wrong, you are "
- "closing a vm backing an allocation that doesn't "
- "exist!\n");
- return;
- }
- down_write(&data->sem);
- if (data->vma == vma) {
- data->vma = NULL;
- if ((data->flags & PMEM_FLAGS_CONNECTED) &&
- (data->flags & PMEM_FLAGS_SUBMAP))
- data->flags |= PMEM_FLAGS_UNSUBMAP;
- }
- /* the kernel is going to free this vma now anyway */
- up_write(&data->sem);
-}
-
-static struct vm_operations_struct vm_ops = {
- .open = pmem_vma_open,
- .close = pmem_vma_close,
-};
-
-static int pmem_mmap(struct file *file, struct vm_area_struct *vma)
-{
- struct pmem_data *data;
- int index;
- unsigned long vma_size = vma->vm_end - vma->vm_start;
- int ret = 0, id = get_id(file);
-
- if (vma->vm_pgoff || !PMEM_IS_PAGE_ALIGNED(vma_size)) {
-#if PMEM_DEBUG
- printk(KERN_ERR "pmem: mmaps must be at offset zero, aligned"
- " and a multiple of pages_size.\n");
-#endif
- return -EINVAL;
- }
-
- data = file->private_data;
- down_write(&data->sem);
- /* check this file isn't already mmaped, for submaps check this file
- * has never been mmaped */
- if ((data->flags & PMEM_FLAGS_MASTERMAP) ||
- (data->flags & PMEM_FLAGS_SUBMAP) ||
- (data->flags & PMEM_FLAGS_UNSUBMAP)) {
-#if PMEM_DEBUG
- printk(KERN_ERR "pmem: you can only mmap a pmem file once, "
- "this file is already mmaped. %x\n", data->flags);
-#endif
- ret = -EINVAL;
- goto error;
- }
- /* if file->private_data == unalloced, alloc*/
- if (data && data->index == -1) {
- down_write(&pmem[id].bitmap_sem);
- index = pmem_allocate(id, vma->vm_end - vma->vm_start);
- up_write(&pmem[id].bitmap_sem);
- data->index = index;
- }
- /* either no space was available or an error occured */
- if (!has_allocation(file)) {
- ret = -EINVAL;
- printk("pmem: could not find allocation for map.\n");
- goto error;
- }
-
- if (pmem_len(id, data) < vma_size) {
-#if PMEM_DEBUG
- printk(KERN_WARNING "pmem: mmap size [%lu] does not match"
- "size of backing region [%lu].\n", vma_size,
- pmem_len(id, data));
-#endif
- ret = -EINVAL;
- goto error;
- }
-
- vma->vm_pgoff = pmem_start_addr(id, data) >> PAGE_SHIFT;
- vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_page_prot);
-
- if (data->flags & PMEM_FLAGS_CONNECTED) {
- struct pmem_region_node *region_node;
- struct list_head *elt;
- if (pmem_map_garbage(id, vma, data, 0, vma_size)) {
- printk("pmem: mmap failed in kernel!\n");
- ret = -EAGAIN;
- goto error;
- }
- list_for_each(elt, &data->region_list) {
- region_node = list_entry(elt, struct pmem_region_node,
- list);
- DLOG("remapping file: %p %lx %lx\n", file,
- region_node->region.offset,
- region_node->region.len);
- if (pmem_remap_pfn_range(id, vma, data,
- region_node->region.offset,
- region_node->region.len)) {
- ret = -EAGAIN;
- goto error;
- }
- }
- data->flags |= PMEM_FLAGS_SUBMAP;
- get_task_struct(current->group_leader);
- data->task = current->group_leader;
- data->vma = vma;
-#if PMEM_DEBUG
- data->pid = current->pid;
-#endif
- DLOG("submmapped file %p vma %p pid %u\n", file, vma,
- current->pid);
- } else {
- if (pmem_map_pfn_range(id, vma, data, 0, vma_size)) {
- printk(KERN_INFO "pmem: mmap failed in kernel!\n");
- ret = -EAGAIN;
- goto error;
- }
- data->flags |= PMEM_FLAGS_MASTERMAP;
- data->pid = current->pid;
- }
- vma->vm_ops = &vm_ops;
-error:
- up_write(&data->sem);
- return ret;
-}
-
-/* the following are the api for accessing pmem regions by other drivers
- * from inside the kernel */
-int get_pmem_user_addr(struct file *file, unsigned long *start,
- unsigned long *len)
-{
- struct pmem_data *data;
- if (!is_pmem_file(file) || !has_allocation(file)) {
-#if PMEM_DEBUG
- printk(KERN_INFO "pmem: requested pmem data from invalid"
- "file.\n");
-#endif
- return -1;
- }
- data = file->private_data;
- down_read(&data->sem);
- if (data->vma) {
- *start = data->vma->vm_start;
- *len = data->vma->vm_end - data->vma->vm_start;
- } else {
- *start = 0;
- *len = 0;
- }
- up_read(&data->sem);
- return 0;
-}
-
-int get_pmem_addr(struct file *file, unsigned long *start,
- unsigned long *vstart, unsigned long *len)
-{
- struct pmem_data *data;
- int id;
-
- if (!is_pmem_file(file) || !has_allocation(file))
- return -1;
-
- data = file->private_data;
- if (data->index == -1) {
-#if PMEM_DEBUG
- printk(KERN_INFO "pmem: requested pmem data from file with no "
- "allocation.\n");
- return -1;
-#endif
- }
- id = get_id(file);
-
- down_read(&data->sem);
- *start = pmem_start_addr(id, data);
- *len = pmem_len(id, data);
- *vstart = (unsigned long)pmem_start_vaddr(id, data);
- up_read(&data->sem);
-#if PMEM_DEBUG
- down_write(&data->sem);
- data->ref++;
- up_write(&data->sem);
-#endif
- return 0;
-}
-
-int get_pmem_file(int fd, unsigned long *start, unsigned long *vstart,
- unsigned long *len, struct file **filp)
-{
- struct file *file;
-
- file = fget(fd);
- if (unlikely(file == NULL)) {
- printk(KERN_INFO "pmem: requested data from file descriptor "
- "that doesn't exist.");
- return -1;
- }
-
- if (get_pmem_addr(file, start, vstart, len))
- goto end;
-
- if (filp)
- *filp = file;
- return 0;
-end:
- fput(file);
- return -1;
-}
-
-void put_pmem_file(struct file *file)
-{
- struct pmem_data *data;
- int id;
-
- if (!is_pmem_file(file))
- return;
- id = get_id(file);
- data = file->private_data;
-#if PMEM_DEBUG
- down_write(&data->sem);
- if (data->ref == 0) {
- printk("pmem: pmem_put > pmem_get %s (pid %d)\n",
- pmem[id].dev.name, data->pid);
- BUG();
- }
- data->ref--;
- up_write(&data->sem);
-#endif
- fput(file);
-}
-
-void flush_pmem_file(struct file *file, unsigned long offset, unsigned long len)
-{
- struct pmem_data *data;
- int id;
- void *vaddr;
- struct pmem_region_node *region_node;
- struct list_head *elt;
- void *flush_start, *flush_end;
-
- if (!is_pmem_file(file) || !has_allocation(file))
- return;
-
- id = get_id(file);
- data = file->private_data;
- if (!pmem[id].cached)
- return;
-
- down_read(&data->sem);
- vaddr = pmem_start_vaddr(id, data);
- /* if this isn't a submmapped file, flush the whole thing */
- if (unlikely(!(data->flags & PMEM_FLAGS_CONNECTED))) {
- dmac_flush_range(vaddr, vaddr + pmem_len(id, data));
- goto end;
- }
- /* otherwise, flush the region of the file we are drawing */
- list_for_each(elt, &data->region_list) {
- region_node = list_entry(elt, struct pmem_region_node, list);
- if ((offset >= region_node->region.offset) &&
- ((offset + len) <= (region_node->region.offset +
- region_node->region.len))) {
- flush_start = vaddr + region_node->region.offset;
- flush_end = flush_start + region_node->region.len;
- dmac_flush_range(flush_start, flush_end);
- break;
- }
- }
-end:
- up_read(&data->sem);
-}
-
-static int pmem_connect(unsigned long connect, struct file *file)
-{
- struct pmem_data *data = file->private_data;
- struct pmem_data *src_data;
- struct file *src_file;
- int ret = 0, put_needed;
-
- down_write(&data->sem);
- /* retrieve the src file and check it is a pmem file with an alloc */
- src_file = fget_light(connect, &put_needed);
- DLOG("connect %p to %p\n", file, src_file);
- if (!src_file) {
- printk(KERN_INFO "pmem: src file not found!\n");
- ret = -EINVAL;
- goto err_no_file;
- }
- if (unlikely(!is_pmem_file(src_file) || !has_allocation(src_file))) {
- printk(KERN_INFO "pmem: src file is not a pmem file or has no "
- "alloc!\n");
- ret = -EINVAL;
- goto err_bad_file;
- }
- src_data = src_file->private_data;
-
- if (has_allocation(file) && (data->index != src_data->index)) {
- printk(KERN_INFO "pmem: file is already mapped but doesn't "
- "match this src_file!\n");
- ret = -EINVAL;
- goto err_bad_file;
- }
- data->index = src_data->index;
- data->flags |= PMEM_FLAGS_CONNECTED;
- data->master_fd = connect;
- data->master_file = src_file;
-
-err_bad_file:
- fput_light(src_file, put_needed);
-err_no_file:
- up_write(&data->sem);
- return ret;
-}
-
-static void pmem_unlock_data_and_mm(struct pmem_data *data,
- struct mm_struct *mm)
-{
- up_write(&data->sem);
- if (mm != NULL) {
- up_write(&mm->mmap_sem);
- mmput(mm);
- }
-}
-
-static int pmem_lock_data_and_mm(struct file *file, struct pmem_data *data,
- struct mm_struct **locked_mm)
-{
- int ret = 0;
- struct mm_struct *mm = NULL;
- *locked_mm = NULL;
-lock_mm:
- down_read(&data->sem);
- if (PMEM_IS_SUBMAP(data)) {
- mm = get_task_mm(data->task);
- if (!mm) {
-#if PMEM_DEBUG
- printk(KERN_DEBUG "pmem: can't remap task is gone!\n");
-#endif
- up_read(&data->sem);
- return -1;
- }
- }
- up_read(&data->sem);
-
- if (mm)
- down_write(&mm->mmap_sem);
-
- down_write(&data->sem);
- /* check that the file didn't get mmaped before we could take the
- * data sem, this should be safe b/c you can only submap each file
- * once */
- if (PMEM_IS_SUBMAP(data) && !mm) {
- pmem_unlock_data_and_mm(data, mm);
- up_write(&data->sem);
- goto lock_mm;
- }
- /* now check that vma.mm is still there, it could have been
- * deleted by vma_close before we could get the data->sem */
- if ((data->flags & PMEM_FLAGS_UNSUBMAP) && (mm != NULL)) {
- /* might as well release this */
- if (data->flags & PMEM_FLAGS_SUBMAP) {
- put_task_struct(data->task);
- data->task = NULL;
- /* lower the submap flag to show the mm is gone */
- data->flags &= ~(PMEM_FLAGS_SUBMAP);
- }
- pmem_unlock_data_and_mm(data, mm);
- return -1;
- }
- *locked_mm = mm;
- return ret;
-}
-
-int pmem_remap(struct pmem_region *region, struct file *file,
- unsigned operation)
-{
- int ret;
- struct pmem_region_node *region_node;
- struct mm_struct *mm = NULL;
- struct list_head *elt, *elt2;
- int id = get_id(file);
- struct pmem_data *data = file->private_data;
-
- /* pmem region must be aligned on a page boundry */
- if (unlikely(!PMEM_IS_PAGE_ALIGNED(region->offset) ||
- !PMEM_IS_PAGE_ALIGNED(region->len))) {
-#if PMEM_DEBUG
- printk(KERN_DEBUG "pmem: request for unaligned pmem "
- "suballocation %lx %lx\n", region->offset, region->len);
-#endif
- return -EINVAL;
- }
-
- /* if userspace requests a region of len 0, there's nothing to do */
- if (region->len == 0)
- return 0;
-
- /* lock the mm and data */
- ret = pmem_lock_data_and_mm(file, data, &mm);
- if (ret)
- return 0;
-
- /* only the owner of the master file can remap the client fds
- * that back in it */
- if (!is_master_owner(file)) {
-#if PMEM_DEBUG
- printk("pmem: remap requested from non-master process\n");
-#endif
- ret = -EINVAL;
- goto err;
- }
-
- /* check that the requested range is within the src allocation */
- if (unlikely((region->offset > pmem_len(id, data)) ||
- (region->len > pmem_len(id, data)) ||
- (region->offset + region->len > pmem_len(id, data)))) {
-#if PMEM_DEBUG
- printk(KERN_INFO "pmem: suballoc doesn't fit in src_file!\n");
-#endif
- ret = -EINVAL;
- goto err;
- }
-
- if (operation == PMEM_MAP) {
- region_node = kmalloc(sizeof(struct pmem_region_node),
- GFP_KERNEL);
- if (!region_node) {
- ret = -ENOMEM;
-#if PMEM_DEBUG
- printk(KERN_INFO "No space to allocate metadata!");
-#endif
- goto err;
- }
- region_node->region = *region;
- list_add(®ion_node->list, &data->region_list);
- } else if (operation == PMEM_UNMAP) {
- int found = 0;
- list_for_each_safe(elt, elt2, &data->region_list) {
- region_node = list_entry(elt, struct pmem_region_node,
- list);
- if (region->len == 0 ||
- (region_node->region.offset == region->offset &&
- region_node->region.len == region->len)) {
- list_del(elt);
- kfree(region_node);
- found = 1;
- }
- }
- if (!found) {
-#if PMEM_DEBUG
- printk("pmem: Unmap region does not map any mapped "
- "region!");
-#endif
- ret = -EINVAL;
- goto err;
- }
- }
-
- if (data->vma && PMEM_IS_SUBMAP(data)) {
- if (operation == PMEM_MAP)
- ret = pmem_remap_pfn_range(id, data->vma, data,
- region->offset, region->len);
- else if (operation == PMEM_UNMAP)
- ret = pmem_unmap_pfn_range(id, data->vma, data,
- region->offset, region->len);
- }
-
-err:
- pmem_unlock_data_and_mm(data, mm);
- return ret;
-}
-
-static void pmem_revoke(struct file *file, struct pmem_data *data)
-{
- struct pmem_region_node *region_node;
- struct list_head *elt, *elt2;
- struct mm_struct *mm = NULL;
- int id = get_id(file);
- int ret = 0;
-
- data->master_file = NULL;
- ret = pmem_lock_data_and_mm(file, data, &mm);
- /* if lock_data_and_mm fails either the task that mapped the fd, or
- * the vma that mapped it have already gone away, nothing more
- * needs to be done */
- if (ret)
- return;
- /* unmap everything */
- /* delete the regions and region list nothing is mapped any more */
- if (data->vma)
- list_for_each_safe(elt, elt2, &data->region_list) {
- region_node = list_entry(elt, struct pmem_region_node,
- list);
- pmem_unmap_pfn_range(id, data->vma, data,
- region_node->region.offset,
- region_node->region.len);
- list_del(elt);
- kfree(region_node);
- }
- /* delete the master file */
- pmem_unlock_data_and_mm(data, mm);
-}
-
-static void pmem_get_size(struct pmem_region *region, struct file *file)
-{
- struct pmem_data *data = file->private_data;
- int id = get_id(file);
-
- if (!has_allocation(file)) {
- region->offset = 0;
- region->len = 0;
- return;
- } else {
- region->offset = pmem_start_addr(id, data);
- region->len = pmem_len(id, data);
- }
- DLOG("offset %lx len %lx\n", region->offset, region->len);
-}
-
-
-static long pmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
- struct pmem_data *data;
- int id = get_id(file);
-
- switch (cmd) {
- case PMEM_GET_PHYS:
- {
- struct pmem_region region;
- DLOG("get_phys\n");
- if (!has_allocation(file)) {
- region.offset = 0;
- region.len = 0;
- } else {
- data = file->private_data;
- region.offset = pmem_start_addr(id, data);
- region.len = pmem_len(id, data);
- }
- printk(KERN_INFO "pmem: request for physical address "
- "of pmem region from process %d.\n", current->pid);
- if (copy_to_user((void __user *)arg, ®ion,
- sizeof(struct pmem_region)))
- return -EFAULT;
- break;
- }
- case PMEM_MAP:
- {
- struct pmem_region region;
- if (copy_from_user(®ion, (void __user *)arg,
- sizeof(struct pmem_region)))
- return -EFAULT;
- data = file->private_data;
- return pmem_remap(®ion, file, PMEM_MAP);
- }
- break;
- case PMEM_UNMAP:
- {
- struct pmem_region region;
- if (copy_from_user(®ion, (void __user *)arg,
- sizeof(struct pmem_region)))
- return -EFAULT;
- data = file->private_data;
- return pmem_remap(®ion, file, PMEM_UNMAP);
- break;
- }
- case PMEM_GET_SIZE:
- {
- struct pmem_region region;
- DLOG("get_size\n");
- pmem_get_size(®ion, file);
- if (copy_to_user((void __user *)arg, ®ion,
- sizeof(struct pmem_region)))
- return -EFAULT;
- break;
- }
- case PMEM_GET_TOTAL_SIZE:
- {
- struct pmem_region region;
- DLOG("get total size\n");
- region.offset = 0;
- get_id(file);
- region.len = pmem[id].size;
- if (copy_to_user((void __user *)arg, ®ion,
- sizeof(struct pmem_region)))
- return -EFAULT;
- break;
- }
- case PMEM_ALLOCATE:
- {
- if (has_allocation(file))
- return -EINVAL;
- data = file->private_data;
- data->index = pmem_allocate(id, arg);
- break;
- }
- case PMEM_CONNECT:
- DLOG("connect\n");
- return pmem_connect(arg, file);
- break;
- default:
- if (pmem[id].ioctl)
- return pmem[id].ioctl(file, cmd, arg);
- return -EINVAL;
- }
- return 0;
-}
-
-#if PMEM_DEBUG
-static ssize_t debug_open(struct inode *inode, struct file *file)
-{
- file->private_data = inode->i_private;
- return 0;
-}
-
-static ssize_t debug_read(struct file *file, char __user *buf, size_t count,
- loff_t *ppos)
-{
- struct list_head *elt, *elt2;
- struct pmem_data *data;
- struct pmem_region_node *region_node;
- int id = (int)file->private_data;
- const int debug_bufmax = 4096;
- static char buffer[4096];
- int n = 0;
-
- DLOG("debug open\n");
- n = scnprintf(buffer, debug_bufmax,
- "pid #: mapped regions (offset, len) (offset,len)...\n");
-
- down(&pmem[id].data_list_sem);
- list_for_each(elt, &pmem[id].data_list) {
- data = list_entry(elt, struct pmem_data, list);
- down_read(&data->sem);
- n += scnprintf(buffer + n, debug_bufmax - n, "pid %u:",
- data->pid);
- list_for_each(elt2, &data->region_list) {
- region_node = list_entry(elt2, struct pmem_region_node,
- list);
- n += scnprintf(buffer + n, debug_bufmax - n,
- "(%lx,%lx) ",
- region_node->region.offset,
- region_node->region.len);
- }
- n += scnprintf(buffer + n, debug_bufmax - n, "\n");
- up_read(&data->sem);
- }
- up(&pmem[id].data_list_sem);
-
- n++;
- buffer[n] = 0;
- return simple_read_from_buffer(buf, count, ppos, buffer, n);
-}
-
-static struct file_operations debug_fops = {
- .read = debug_read,
- .open = debug_open,
-};
-#endif
-
-#if 0
-static struct miscdevice pmem_dev = {
- .name = "pmem",
- .fops = &pmem_fops,
-};
-#endif
-
-int pmem_setup(struct android_pmem_platform_data *pdata,
- long (*ioctl)(struct file *, unsigned int, unsigned long),
- int (*release)(struct inode *, struct file *))
-{
- int err = 0;
- int i, index = 0;
- int id = id_count;
- id_count++;
-
- pmem[id].no_allocator = pdata->no_allocator;
- pmem[id].cached = pdata->cached;
- pmem[id].buffered = pdata->buffered;
- pmem[id].base = pdata->start;
- pmem[id].size = pdata->size;
- pmem[id].ioctl = ioctl;
- pmem[id].release = release;
- init_rwsem(&pmem[id].bitmap_sem);
- init_MUTEX(&pmem[id].data_list_sem);
- INIT_LIST_HEAD(&pmem[id].data_list);
- pmem[id].dev.name = pdata->name;
- pmem[id].dev.minor = id;
- pmem[id].dev.fops = &pmem_fops;
- printk(KERN_INFO "%s: %d init\n", pdata->name, pdata->cached);
-
- err = misc_register(&pmem[id].dev);
- if (err) {
- printk(KERN_ALERT "Unable to register pmem driver!\n");
- goto err_cant_register_device;
- }
- pmem[id].num_entries = pmem[id].size / PMEM_MIN_ALLOC;
-
- pmem[id].bitmap = kcalloc(pmem[id].num_entries,
- sizeof(struct pmem_bits), GFP_KERNEL);
- if (!pmem[id].bitmap)
- goto err_no_mem_for_metadata;
-
- for (i = sizeof(pmem[id].num_entries) * 8 - 1; i >= 0; i--) {
- if ((pmem[id].num_entries) & 1<<i) {
- PMEM_ORDER(id, index) = i;
- index = PMEM_NEXT_INDEX(id, index);
- }
- }
-
- if (pmem[id].cached)
- pmem[id].vbase = ioremap_cached(pmem[id].base,
- pmem[id].size);
-#ifdef ioremap_ext_buffered
- else if (pmem[id].buffered)
- pmem[id].vbase = ioremap_ext_buffered(pmem[id].base,
- pmem[id].size);
-#endif
- else
- pmem[id].vbase = ioremap(pmem[id].base, pmem[id].size);
-
- if (pmem[id].vbase == 0)
- goto error_cant_remap;
-
- pmem[id].garbage_pfn = page_to_pfn(alloc_page(GFP_KERNEL));
- if (pmem[id].no_allocator)
- pmem[id].allocated = 0;
-
-#if PMEM_DEBUG
- debugfs_create_file(pdata->name, S_IFREG | S_IRUGO, NULL, (void *)id,
- &debug_fops);
-#endif
- return 0;
-error_cant_remap:
- kfree(pmem[id].bitmap);
-err_no_mem_for_metadata:
- misc_deregister(&pmem[id].dev);
-err_cant_register_device:
- return -1;
-}
-
-static int pmem_probe(struct platform_device *pdev)
-{
- struct android_pmem_platform_data *pdata;
-
- if (!pdev || !pdev->dev.platform_data) {
- printk(KERN_ALERT "Unable to probe pmem!\n");
- return -1;
- }
- pdata = pdev->dev.platform_data;
- return pmem_setup(pdata, NULL, NULL);
-}
-
-
-static int pmem_remove(struct platform_device *pdev)
-{
- int id = pdev->id;
- __free_page(pfn_to_page(pmem[id].garbage_pfn));
- misc_deregister(&pmem[id].dev);
- return 0;
-}
-
-static struct platform_driver pmem_driver = {
- .probe = pmem_probe,
- .remove = pmem_remove,
- .driver = { .name = "android_pmem" }
-};
-
-
-static int __init pmem_init(void)
-{
- return platform_driver_register(&pmem_driver);
-}
-
-static void __exit pmem_exit(void)
-{
- platform_driver_unregister(&pmem_driver);
-}
-
-module_init(pmem_init);
-module_exit(pmem_exit);
-
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