diff options
Diffstat (limited to 'drivers/misc/hwmem/hwmem-main.c')
| -rw-r--r-- | drivers/misc/hwmem/hwmem-main.c | 726 |
1 files changed, 726 insertions, 0 deletions
diff --git a/drivers/misc/hwmem/hwmem-main.c b/drivers/misc/hwmem/hwmem-main.c new file mode 100644 index 00000000000..b91d99bc2be --- /dev/null +++ b/drivers/misc/hwmem/hwmem-main.c @@ -0,0 +1,726 @@ +/* + * Copyright (C) ST-Ericsson SA 2010 + * + * Hardware memory driver, hwmem + * + * Author: Marcus Lorentzon <marcus.xm.lorentzon@stericsson.com>, + * Johan Mossberg <johan.xx.mossberg@stericsson.com> for ST-Ericsson. + * + * License terms: GNU General Public License (GPL), version 2. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/idr.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/pid.h> +#include <linux/list.h> +#include <linux/hwmem.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/io.h> +#include <linux/kallsyms.h> +#include <linux/vmalloc.h> +#include "cache_handler.h" + +#define S32_MAX 2147483647 + +struct hwmem_alloc_threadg_info { + struct list_head list; + + struct pid *threadg_pid; /* Ref counted */ + + enum hwmem_access access; +}; + +struct hwmem_alloc { + struct list_head list; + + atomic_t ref_cnt; + + enum hwmem_alloc_flags flags; + struct hwmem_mem_type_struct *mem_type; + + void *allocator_hndl; + phys_addr_t paddr; + void *kaddr; + size_t size; + s32 name; + + /* Access control */ + enum hwmem_access default_access; + struct list_head threadg_info_list; + + /* Cache handling */ + struct cach_buf cach_buf; + +#ifdef CONFIG_DEBUG_FS + /* Debug */ + void *creator; + pid_t creator_tgid; +#endif /* #ifdef CONFIG_DEBUG_FS */ +}; + +static struct platform_device *hwdev; + +static LIST_HEAD(alloc_list); +static DEFINE_IDR(global_idr); +static DEFINE_MUTEX(lock); + +static void vm_open(struct vm_area_struct *vma); +static void vm_close(struct vm_area_struct *vma); +static struct vm_operations_struct vm_ops = { + .open = vm_open, + .close = vm_close, +}; + +static void kunmap_alloc(struct hwmem_alloc *alloc); + +/* Helpers */ + +static void destroy_alloc_threadg_info( + struct hwmem_alloc_threadg_info *info) +{ + if (info->threadg_pid) + put_pid(info->threadg_pid); + + kfree(info); +} + +static void clean_alloc_threadg_info_list(struct hwmem_alloc *alloc) +{ + struct hwmem_alloc_threadg_info *info; + struct hwmem_alloc_threadg_info *tmp; + + list_for_each_entry_safe(info, tmp, &(alloc->threadg_info_list), + list) { + list_del(&info->list); + destroy_alloc_threadg_info(info); + } +} + +static enum hwmem_access get_access(struct hwmem_alloc *alloc) +{ + struct hwmem_alloc_threadg_info *info; + struct pid *my_pid; + bool found = false; + + my_pid = find_get_pid(task_tgid_nr(current)); + if (!my_pid) + return 0; + + list_for_each_entry(info, &(alloc->threadg_info_list), list) { + if (info->threadg_pid == my_pid) { + found = true; + break; + } + } + + put_pid(my_pid); + + if (found) + return info->access; + else + return alloc->default_access; +} + +static void clear_alloc_mem(struct hwmem_alloc *alloc) +{ + cach_set_domain(&alloc->cach_buf, HWMEM_ACCESS_WRITE, + HWMEM_DOMAIN_CPU, NULL); + + memset(alloc->kaddr, 0, alloc->size); +} + +static void destroy_alloc(struct hwmem_alloc *alloc) +{ + list_del(&alloc->list); + + if (alloc->name != 0) { + idr_remove(&global_idr, alloc->name); + alloc->name = 0; + } + + clean_alloc_threadg_info_list(alloc); + + kunmap_alloc(alloc); + + if (!IS_ERR_OR_NULL(alloc->allocator_hndl)) + alloc->mem_type->allocator_api.free( + alloc->mem_type->allocator_instance, + alloc->allocator_hndl); + + kfree(alloc); +} + +static int kmap_alloc(struct hwmem_alloc *alloc) +{ + int ret; + pgprot_t pgprot; + void *alloc_kaddr; + + alloc_kaddr = alloc->mem_type->allocator_api.get_alloc_kaddr( + alloc->mem_type->allocator_instance, alloc->allocator_hndl); + if (IS_ERR(alloc_kaddr)) + return PTR_ERR(alloc_kaddr); + + pgprot = PAGE_KERNEL; + cach_set_pgprot_cache_options(&alloc->cach_buf, &pgprot); + + ret = ioremap_page_range((unsigned long)alloc_kaddr, + (unsigned long)alloc_kaddr + alloc->size, alloc->paddr, pgprot); + if (ret < 0) { + dev_warn(&hwdev->dev, "Failed to map %#x - %#x", alloc->paddr, + alloc->paddr + alloc->size); + return ret; + } + + alloc->kaddr = alloc_kaddr; + + return 0; +} + +static void kunmap_alloc(struct hwmem_alloc *alloc) +{ + if (alloc->kaddr == NULL) + return; + + unmap_kernel_range((unsigned long)alloc->kaddr, alloc->size); + + alloc->kaddr = NULL; +} + +static struct hwmem_mem_type_struct *resolve_mem_type( + enum hwmem_mem_type mem_type) +{ + unsigned int i; + for (i = 0; i < hwmem_num_mem_types; i++) { + if (hwmem_mem_types[i].id == mem_type) + return &hwmem_mem_types[i]; + } + + return ERR_PTR(-ENOENT); +} + +/* HWMEM API */ + +struct hwmem_alloc *hwmem_alloc(size_t size, enum hwmem_alloc_flags flags, + enum hwmem_access def_access, enum hwmem_mem_type mem_type) +{ + int ret; + struct hwmem_alloc *alloc; + + if (hwdev == NULL) { + printk(KERN_ERR "HWMEM: Badly configured\n"); + return ERR_PTR(-ENOMSG); + } + + if (size == 0) + return ERR_PTR(-EINVAL); + + mutex_lock(&lock); + + size = PAGE_ALIGN(size); + + alloc = kzalloc(sizeof(struct hwmem_alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto alloc_alloc_failed; + } + + INIT_LIST_HEAD(&alloc->list); + atomic_inc(&alloc->ref_cnt); + alloc->flags = flags; + alloc->default_access = def_access; + INIT_LIST_HEAD(&alloc->threadg_info_list); +#ifdef CONFIG_DEBUG_FS + alloc->creator = __builtin_return_address(0); + alloc->creator_tgid = task_tgid_nr(current); +#endif + alloc->mem_type = resolve_mem_type(mem_type); + if (IS_ERR(alloc->mem_type)) { + ret = PTR_ERR(alloc->mem_type); + goto resolve_mem_type_failed; + } + + alloc->allocator_hndl = alloc->mem_type->allocator_api.alloc( + alloc->mem_type->allocator_instance, size); + if (IS_ERR(alloc->allocator_hndl)) { + ret = PTR_ERR(alloc->allocator_hndl); + goto allocator_failed; + } + + alloc->paddr = alloc->mem_type->allocator_api.get_alloc_paddr( + alloc->allocator_hndl); + alloc->size = alloc->mem_type->allocator_api.get_alloc_size( + alloc->allocator_hndl); + + cach_init_buf(&alloc->cach_buf, alloc->flags, alloc->size); + ret = kmap_alloc(alloc); + if (ret < 0) + goto kmap_alloc_failed; + cach_set_buf_addrs(&alloc->cach_buf, alloc->kaddr, alloc->paddr); + + list_add_tail(&alloc->list, &alloc_list); + + clear_alloc_mem(alloc); + + goto out; + +kmap_alloc_failed: +allocator_failed: +resolve_mem_type_failed: + destroy_alloc(alloc); +alloc_alloc_failed: + alloc = ERR_PTR(ret); + +out: + mutex_unlock(&lock); + + return alloc; +} +EXPORT_SYMBOL(hwmem_alloc); + +void hwmem_release(struct hwmem_alloc *alloc) +{ + mutex_lock(&lock); + + if (atomic_dec_and_test(&alloc->ref_cnt)) + destroy_alloc(alloc); + + mutex_unlock(&lock); +} +EXPORT_SYMBOL(hwmem_release); + +int hwmem_set_domain(struct hwmem_alloc *alloc, enum hwmem_access access, + enum hwmem_domain domain, struct hwmem_region *region) +{ + mutex_lock(&lock); + + cach_set_domain(&alloc->cach_buf, access, domain, region); + + mutex_unlock(&lock); + + return 0; +} +EXPORT_SYMBOL(hwmem_set_domain); + +int hwmem_pin(struct hwmem_alloc *alloc, struct hwmem_mem_chunk *mem_chunks, + u32 *mem_chunks_length) +{ + if (*mem_chunks_length < 1) { + *mem_chunks_length = 1; + return -ENOSPC; + } + + mutex_lock(&lock); + + mem_chunks[0].paddr = alloc->paddr; + mem_chunks[0].size = alloc->size; + *mem_chunks_length = 1; + + mutex_unlock(&lock); + + return 0; +} +EXPORT_SYMBOL(hwmem_pin); + +void hwmem_unpin(struct hwmem_alloc *alloc) +{ +} +EXPORT_SYMBOL(hwmem_unpin); + +static void vm_open(struct vm_area_struct *vma) +{ + atomic_inc(&((struct hwmem_alloc *)vma->vm_private_data)->ref_cnt); +} + +static void vm_close(struct vm_area_struct *vma) +{ + hwmem_release((struct hwmem_alloc *)vma->vm_private_data); +} + +int hwmem_mmap(struct hwmem_alloc *alloc, struct vm_area_struct *vma) +{ + int ret = 0; + unsigned long vma_size = vma->vm_end - vma->vm_start; + enum hwmem_access access; + mutex_lock(&lock); + + access = get_access(alloc); + + /* Check permissions */ + if ((!(access & HWMEM_ACCESS_WRITE) && + (vma->vm_flags & VM_WRITE)) || + (!(access & HWMEM_ACCESS_READ) && + (vma->vm_flags & VM_READ))) { + ret = -EPERM; + goto illegal_access; + } + + if (vma_size > alloc->size) { + ret = -EINVAL; + goto illegal_size; + } + + /* + * We don't want Linux to do anything (merging etc) with our VMAs as + * the offset is not necessarily valid + */ + vma->vm_flags |= VM_SPECIAL; + cach_set_pgprot_cache_options(&alloc->cach_buf, &vma->vm_page_prot); + vma->vm_private_data = (void *)alloc; + atomic_inc(&alloc->ref_cnt); + vma->vm_ops = &vm_ops; + + ret = remap_pfn_range(vma, vma->vm_start, alloc->paddr >> PAGE_SHIFT, + min(vma_size, (unsigned long)alloc->size), vma->vm_page_prot); + if (ret < 0) + goto map_failed; + + goto out; + +map_failed: + atomic_dec(&alloc->ref_cnt); +illegal_size: +illegal_access: + +out: + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_mmap); + +void *hwmem_kmap(struct hwmem_alloc *alloc) +{ + void *ret; + + mutex_lock(&lock); + + ret = alloc->kaddr; + + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_kmap); + +void hwmem_kunmap(struct hwmem_alloc *alloc) +{ +} +EXPORT_SYMBOL(hwmem_kunmap); + +int hwmem_set_access(struct hwmem_alloc *alloc, + enum hwmem_access access, pid_t pid_nr) +{ + int ret; + struct hwmem_alloc_threadg_info *info; + struct pid *pid; + bool found = false; + + pid = find_get_pid(pid_nr); + if (!pid) { + ret = -EINVAL; + goto error_get_pid; + } + + list_for_each_entry(info, &(alloc->threadg_info_list), list) { + if (info->threadg_pid == pid) { + found = true; + break; + } + } + + if (!found) { + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + ret = -ENOMEM; + goto error_alloc_info; + } + + info->threadg_pid = pid; + info->access = access; + + list_add_tail(&(info->list), &(alloc->threadg_info_list)); + } else { + info->access = access; + } + + return 0; + +error_alloc_info: + put_pid(pid); +error_get_pid: + return ret; +} +EXPORT_SYMBOL(hwmem_set_access); + +void hwmem_get_info(struct hwmem_alloc *alloc, u32 *size, + enum hwmem_mem_type *mem_type, enum hwmem_access *access) +{ + mutex_lock(&lock); + + if (size != NULL) + *size = alloc->size; + if (mem_type != NULL) + *mem_type = alloc->mem_type->id; + if (access != NULL) + *access = get_access(alloc); + + mutex_unlock(&lock); +} +EXPORT_SYMBOL(hwmem_get_info); + +s32 hwmem_get_name(struct hwmem_alloc *alloc) +{ + int ret = 0, name; + + mutex_lock(&lock); + + if (alloc->name != 0) { + ret = alloc->name; + goto out; + } + + while (true) { + if (idr_pre_get(&global_idr, GFP_KERNEL) == 0) { + ret = -ENOMEM; + goto pre_get_id_failed; + } + + ret = idr_get_new_above(&global_idr, alloc, 1, &name); + if (ret == 0) + break; + else if (ret != -EAGAIN) + goto get_id_failed; + } + + if (name > S32_MAX) { + ret = -ENOMSG; + goto overflow; + } + + alloc->name = name; + + ret = name; + goto out; + +overflow: + idr_remove(&global_idr, name); +get_id_failed: +pre_get_id_failed: + +out: + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_get_name); + +struct hwmem_alloc *hwmem_resolve_by_name(s32 name) +{ + struct hwmem_alloc *alloc; + + mutex_lock(&lock); + + alloc = idr_find(&global_idr, name); + if (alloc == NULL) { + alloc = ERR_PTR(-EINVAL); + goto find_failed; + } + atomic_inc(&alloc->ref_cnt); + + goto out; + +find_failed: + +out: + mutex_unlock(&lock); + + return alloc; +} +EXPORT_SYMBOL(hwmem_resolve_by_name); + +/* Debug */ + +#ifdef CONFIG_DEBUG_FS + +static int debugfs_allocs_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos); + +static const struct file_operations debugfs_allocs_fops = { + .owner = THIS_MODULE, + .read = debugfs_allocs_read, +}; + +static int print_alloc(struct hwmem_alloc *alloc, char **buf, size_t buf_size) +{ + int ret; + char creator[KSYM_SYMBOL_LEN]; + int i; + + if (sprint_symbol(creator, (unsigned long)alloc->creator) < 0) + creator[0] = '\0'; + + for (i = 0; i < 2; i++) { + size_t buf_size_l; + if (i == 0) + buf_size_l = 0; + else + buf_size_l = buf_size; + + ret = snprintf(*buf, buf_size_l, + "%#x\n" + "\tSize: %u\n" + "\tMemory type: %u\n" + "\tName: %#x\n" + "\tReference count: %i\n" + "\tAllocation flags: %#x\n" + "\t$ settings: %#x\n" + "\tDefault access: %#x\n" + "\tPhysical address: %#x\n" + "\tKernel virtual address: %#x\n" + "\tCreator: %s\n" + "\tCreator thread group id: %u\n", + (unsigned int)alloc, alloc->size, alloc->mem_type->id, + alloc->name, atomic_read(&alloc->ref_cnt), + alloc->flags, alloc->cach_buf.cache_settings, + alloc->default_access, alloc->paddr, + (unsigned int)alloc->kaddr, creator, + alloc->creator_tgid); + if (ret < 0) + return -ENOMSG; + else if (ret + 1 > buf_size) + return -EINVAL; + } + + *buf += ret; + + return 0; +} + +static int debugfs_allocs_read(struct file *file, char __user *buf, + size_t count, loff_t *f_pos) +{ + /* + * We assume the supplied buffer and PAGE_SIZE is large enough to hold + * information about at least one alloc, if not no data will be + * returned. + */ + + int ret; + size_t i = 0; + struct hwmem_alloc *curr_alloc; + char *local_buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + char *local_buf_pos = local_buf; + size_t available_space = min((size_t)PAGE_SIZE, count); + /* private_data is intialized to NULL in open which I assume is 0. */ + void **curr_pos = &file->private_data; + size_t bytes_read; + + if (local_buf == NULL) + return -ENOMEM; + + mutex_lock(&lock); + + list_for_each_entry(curr_alloc, &alloc_list, list) { + if (i++ < (size_t)*curr_pos) + continue; + + ret = print_alloc(curr_alloc, &local_buf_pos, available_space - + (size_t)(local_buf_pos - local_buf)); + if (ret == -EINVAL) /* No more room */ + break; + else if (ret < 0) + goto out; + + *curr_pos = (void *)i; + } + + bytes_read = (size_t)(local_buf_pos - local_buf); + + ret = copy_to_user(buf, local_buf, bytes_read); + if (ret < 0) + goto out; + + ret = bytes_read; + +out: + kfree(local_buf); + + mutex_unlock(&lock); + + return ret; +} + +static void init_debugfs(void) +{ + /* Hwmem is never unloaded so dropping the dentrys is ok. */ + struct dentry *debugfs_root_dir = debugfs_create_dir("hwmem", NULL); + (void)debugfs_create_file("allocs", 0444, debugfs_root_dir, 0, + &debugfs_allocs_fops); +} + +#endif /* #ifdef CONFIG_DEBUG_FS */ + +/* Module */ + +extern int hwmem_ioctl_init(void); + +static int __devinit hwmem_probe(struct platform_device *pdev) +{ + int ret; + + if (hwdev) { + dev_err(&pdev->dev, "Probed multiple times\n"); + return -EINVAL; + } + + hwdev = pdev; + + /* + * No need to flush the caches here. If we can keep track of the cache + * content then none of our memory will be in the caches, if we can't + * keep track of the cache content we always assume all our memory is + * in the caches. + */ + + ret = hwmem_ioctl_init(); + if (ret < 0) + dev_warn(&pdev->dev, "Failed to start hwmem-ioctl, continuing" + " anyway\n"); + +#ifdef CONFIG_DEBUG_FS + init_debugfs(); +#endif + + dev_info(&pdev->dev, "Probed OK\n"); + + return 0; +} + +static struct platform_driver hwmem_driver = { + .probe = hwmem_probe, + .driver = { + .name = "hwmem", + }, +}; + +static int __init hwmem_init(void) +{ + return platform_driver_register(&hwmem_driver); +} +subsys_initcall(hwmem_init); + +MODULE_AUTHOR("Marcus Lorentzon <marcus.xm.lorentzon@stericsson.com>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Hardware memory driver"); + |