diff options
Diffstat (limited to 'drivers/misc/hwmem/contig_alloc.c')
| -rw-r--r-- | drivers/misc/hwmem/contig_alloc.c | 571 |
1 files changed, 571 insertions, 0 deletions
diff --git a/drivers/misc/hwmem/contig_alloc.c b/drivers/misc/hwmem/contig_alloc.c new file mode 100644 index 00000000000..31533ed5988 --- /dev/null +++ b/drivers/misc/hwmem/contig_alloc.c @@ -0,0 +1,571 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * Contiguous memory allocator + * + * 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/kernel.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/vmalloc.h> +#include <asm/sizes.h> + +#define MAX_INSTANCE_NAME_LENGTH 31 + +struct alloc { + struct list_head list; + + bool in_use; + phys_addr_t paddr; + size_t size; +}; + +struct instance { + struct list_head list; + + char name[MAX_INSTANCE_NAME_LENGTH + 1]; + + phys_addr_t region_paddr; + void *region_kaddr; + size_t region_size; + + struct list_head alloc_list; + +#ifdef CONFIG_DEBUG_FS + struct inode *debugfs_inode; + int cona_status_free; + int cona_status_used; + int cona_status_max_cont; + int cona_status_max_check; + int cona_status_biggest_free; + int cona_status_printed; +#endif /* #ifdef CONFIG_DEBUG_FS */ +}; + +static LIST_HEAD(instance_list); + +static DEFINE_MUTEX(lock); + +void *cona_create(const char *name, phys_addr_t region_paddr, + size_t region_size); +void *cona_alloc(void *instance, size_t size); +void cona_free(void *instance, void *alloc); +phys_addr_t cona_get_alloc_paddr(void *alloc); +void *cona_get_alloc_kaddr(void *instance, void *alloc); +size_t cona_get_alloc_size(void *alloc); + +static int init_alloc_list(struct instance *instance); +static void clean_alloc_list(struct instance *instance); +static struct alloc *find_free_alloc_bestfit(struct instance *instance, + size_t size); +static struct alloc *split_allocation(struct alloc *alloc, + size_t new_alloc_size); +static phys_addr_t get_alloc_offset(struct instance *instance, + struct alloc *alloc); + +void *cona_create(const char *name, phys_addr_t region_paddr, + size_t region_size) +{ + int ret; + struct instance *instance; + struct vm_struct *vm_area; + + if (region_size == 0) + return ERR_PTR(-EINVAL); + + instance = kzalloc(sizeof(*instance), GFP_KERNEL); + if (instance == NULL) + return ERR_PTR(-ENOMEM); + + memcpy(instance->name, name, MAX_INSTANCE_NAME_LENGTH + 1); + /* Truncate name if necessary */ + instance->name[MAX_INSTANCE_NAME_LENGTH] = '\0'; + instance->region_paddr = region_paddr; + instance->region_size = region_size; + + vm_area = get_vm_area(region_size, VM_IOREMAP); + if (vm_area == NULL) { + printk(KERN_WARNING "CONA: Failed to allocate %u bytes" + " kernel virtual memory", region_size); + ret = -ENOMSG; + goto vmem_alloc_failed; + } + instance->region_kaddr = vm_area->addr; + + INIT_LIST_HEAD(&instance->alloc_list); + ret = init_alloc_list(instance); + if (ret < 0) + goto init_alloc_list_failed; + + mutex_lock(&lock); + list_add_tail(&instance->list, &instance_list); + mutex_unlock(&lock); + + return instance; + +init_alloc_list_failed: + vm_area = remove_vm_area(instance->region_kaddr); + if (vm_area == NULL) + printk(KERN_ERR "CONA: Failed to free kernel virtual memory," + " resource leak!\n"); + + kfree(vm_area); +vmem_alloc_failed: + kfree(instance); + + return ERR_PTR(ret); +} + +void *cona_alloc(void *instance, size_t size) +{ + struct instance *instance_l = (struct instance *)instance; + struct alloc *alloc; + + if (size == 0) + return ERR_PTR(-EINVAL); + + mutex_lock(&lock); + + alloc = find_free_alloc_bestfit(instance_l, size); + if (IS_ERR(alloc)) + goto out; + if (size < alloc->size) { + alloc = split_allocation(alloc, size); + if (IS_ERR(alloc)) + goto out; + } else { + alloc->in_use = true; + } +#ifdef CONFIG_DEBUG_FS + instance_l->cona_status_max_cont += alloc->size; + instance_l->cona_status_max_check = + max(instance_l->cona_status_max_check, + instance_l->cona_status_max_cont); +#endif /* #ifdef CONFIG_DEBUG_FS */ + +out: + mutex_unlock(&lock); + + return alloc; +} + +void cona_free(void *instance, void *alloc) +{ + struct instance *instance_l = (struct instance *)instance; + struct alloc *alloc_l = (struct alloc *)alloc; + struct alloc *other; + + mutex_lock(&lock); + + alloc_l->in_use = false; + +#ifdef CONFIG_DEBUG_FS + instance_l->cona_status_max_cont -= alloc_l->size; +#endif /* #ifdef CONFIG_DEBUG_FS */ + + other = list_entry(alloc_l->list.prev, struct alloc, list); + if ((alloc_l->list.prev != &instance_l->alloc_list) && + !other->in_use) { + other->size += alloc_l->size; + list_del(&alloc_l->list); + kfree(alloc_l); + alloc_l = other; + } + other = list_entry(alloc_l->list.next, struct alloc, list); + if ((alloc_l->list.next != &instance_l->alloc_list) && + !other->in_use) { + alloc_l->size += other->size; + list_del(&other->list); + kfree(other); + } + + mutex_unlock(&lock); +} + +phys_addr_t cona_get_alloc_paddr(void *alloc) +{ + return ((struct alloc *)alloc)->paddr; +} + +void *cona_get_alloc_kaddr(void *instance, void *alloc) +{ + struct instance *instance_l = (struct instance *)instance; + + return instance_l->region_kaddr + get_alloc_offset(instance_l, + (struct alloc *)alloc); +} + +size_t cona_get_alloc_size(void *alloc) +{ + return ((struct alloc *)alloc)->size; +} + +static int init_alloc_list(struct instance *instance) +{ + /* + * Hack to not get any allocs that cross a 64MiB boundary as B2R2 can't + * handle that. + */ + int ret; + u32 curr_pos = instance->region_paddr; + u32 region_end = instance->region_paddr + instance->region_size; + u32 next_64mib_boundary = (curr_pos + SZ_64M) & ~(SZ_64M - 1); + struct alloc *alloc; + + if (PAGE_SIZE >= SZ_64M) { + printk(KERN_WARNING "CONA: PAGE_SIZE >= 64MiB\n"); + return -ENOMSG; + } + + while (next_64mib_boundary < region_end) { + if (next_64mib_boundary - curr_pos > PAGE_SIZE) { + alloc = kzalloc(sizeof(struct alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = next_64mib_boundary - curr_pos - + PAGE_SIZE; + alloc->in_use = false; + list_add_tail(&alloc->list, &instance->alloc_list); + curr_pos = alloc->paddr + alloc->size; + } + + alloc = kzalloc(sizeof(struct alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = PAGE_SIZE; + alloc->in_use = true; + list_add_tail(&alloc->list, &instance->alloc_list); + curr_pos = alloc->paddr + alloc->size; + +#ifdef CONFIG_DEBUG_FS + instance->cona_status_max_cont += alloc->size; +#endif /* #ifdef CONFIG_DEBUG_FS */ + + next_64mib_boundary += SZ_64M; + } + + alloc = kzalloc(sizeof(struct alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = region_end - curr_pos; + alloc->in_use = false; + list_add_tail(&alloc->list, &instance->alloc_list); + + return 0; + +error: + clean_alloc_list(instance); + + return ret; +} + +static void clean_alloc_list(struct instance *instance) +{ + while (list_empty(&instance->alloc_list) == 0) { + struct alloc *i = list_first_entry(&instance->alloc_list, + struct alloc, list); + + list_del(&i->list); + + kfree(i); + } +} + +static struct alloc *find_free_alloc_bestfit(struct instance *instance, + size_t size) +{ + size_t best_diff = ~(size_t)0; + struct alloc *alloc = NULL, *i; + + list_for_each_entry(i, &instance->alloc_list, list) { + size_t diff = i->size - size; + if (i->in_use || i->size < size) + continue; + if (diff < best_diff) { + alloc = i; + best_diff = diff; + } + } + + return alloc != NULL ? alloc : ERR_PTR(-ENOMEM); +} + +static struct alloc *split_allocation(struct alloc *alloc, + size_t new_alloc_size) +{ + struct alloc *new_alloc; + + new_alloc = kzalloc(sizeof(struct alloc), GFP_KERNEL); + if (new_alloc == NULL) + return ERR_PTR(-ENOMEM); + + new_alloc->in_use = true; + new_alloc->paddr = alloc->paddr; + new_alloc->size = new_alloc_size; + alloc->size -= new_alloc_size; + alloc->paddr += new_alloc_size; + + list_add_tail(&new_alloc->list, &alloc->list); + + return new_alloc; +} + +static phys_addr_t get_alloc_offset(struct instance *instance, + struct alloc *alloc) +{ + return alloc->paddr - instance->region_paddr; +} + +/* Debug */ + +#ifdef CONFIG_DEBUG_FS + +static int print_alloc(struct instance *instance, struct alloc *alloc, + char **buf, size_t buf_size); +static int print_alloc_status(struct instance *instance, char **buf, + size_t buf_size); +static struct instance *get_instance_from_file(struct file *file); +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 instance *instance, struct alloc *alloc, + char **buf, size_t buf_size) +{ + int ret; + int i; + + for (i = 0; i < 2; i++) { + size_t buf_size_l; + if (i == 0) + buf_size_l = 0; + else + buf_size_l = buf_size; + + if (i == 1) { + if (alloc->in_use) + instance->cona_status_used += alloc->size; + else + instance->cona_status_free += alloc->size; + } + + if (!alloc->in_use) { + instance->cona_status_biggest_free = + max((size_t)alloc->size, + (size_t)instance->cona_status_biggest_free); + } + + ret = snprintf(*buf, buf_size_l, "paddr: %10x\tsize: %10u\t" + "in use: %1u\t used: %10u (%dMB)" + " \t free: %10u (%dMB)\n", + alloc->paddr, + alloc->size, + alloc->in_use, + instance->cona_status_used, + instance->cona_status_used/1024/1024, + instance->cona_status_free, + instance->cona_status_free/1024/1024); + + if (ret < 0) + return -ENOMSG; + else if (ret + 1 > buf_size) + return -EINVAL; + } + + *buf += ret; + + return 0; +} + +static int print_alloc_status(struct instance *instance, char **buf, + size_t buf_size) +{ + int ret; + int i; + + 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, "Overall peak usage:\t%10u " + "(%dMB)\nCurrent max usage:\t%10u (%dMB)\n" + "Current biggest free:\t%10d (%dMB)\n", + instance->cona_status_max_check, + instance->cona_status_max_check/1024/1024, + instance->cona_status_max_cont, + instance->cona_status_max_cont/1024/1024, + instance->cona_status_biggest_free, + instance->cona_status_biggest_free/1024/1024); + + if (ret < 0) + return -ENOMSG; + else if (ret + 1 > buf_size) + return -EINVAL; + } + + *buf += ret; + + return 0; +} + +static struct instance *get_instance_from_file(struct file *file) +{ + struct instance *curr_instance; + + list_for_each_entry(curr_instance, &instance_list, list) { + if (file->f_dentry->d_inode == curr_instance->debugfs_inode) + return curr_instance; + } + + return ERR_PTR(-ENOENT); +} + +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; + struct instance *instance; + struct 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; + bool readout_aborted = false; + + if (local_buf == NULL) + return -ENOMEM; + + mutex_lock(&lock); + instance = get_instance_from_file(file); + if (IS_ERR(instance)) { + ret = PTR_ERR(instance); + goto out; + } + + list_for_each_entry(curr_alloc, &instance->alloc_list, list) { + phys_addr_t alloc_offset = get_alloc_offset(instance, + curr_alloc); + if (alloc_offset < (phys_addr_t)*curr_pos) + continue; + + ret = print_alloc(instance, curr_alloc, &local_buf_pos, + available_space - (size_t)(local_buf_pos - + local_buf)); + + if (ret == -EINVAL) { /* No more room */ + readout_aborted = true; + break; + } else if (ret < 0) { + goto out; + } + /* + * There could be an overflow issue here in the unlikely case + * where the region is placed at the end of the address range + * and the last alloc is 1 byte large. Since this is debug code + * and that case most likely never will happen I've chosen to + * defer fixing it till it happens. + */ + *curr_pos = (void *)(alloc_offset + 1); + + /* Make sure to also print status if there were any prints */ + instance->cona_status_printed = false; + } + + if (!readout_aborted && !instance->cona_status_printed) { + ret = print_alloc_status(instance, &local_buf_pos, + available_space - + (size_t)(local_buf_pos - local_buf)); + + if (ret == -EINVAL) /* No more room */ + readout_aborted = true; + else if (ret < 0) + goto out; + else + instance->cona_status_printed = true; + } + + if (!readout_aborted) { + instance->cona_status_free = 0; + instance->cona_status_used = 0; + instance->cona_status_biggest_free = 0; + } + + 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 int __init init_debugfs(void) +{ + struct instance *curr_instance; + struct dentry *debugfs_root_dir = debugfs_create_dir("cona", NULL); + + mutex_lock(&lock); + + list_for_each_entry(curr_instance, &instance_list, list) { + struct dentry *file_dentry; + char tmp_str[MAX_INSTANCE_NAME_LENGTH + 7 + 1]; + tmp_str[0] = '\0'; + strcat(tmp_str, curr_instance->name); + strcat(tmp_str, "_allocs"); + file_dentry = debugfs_create_file(tmp_str, 0444, + debugfs_root_dir, 0, &debugfs_allocs_fops); + if (file_dentry != NULL) + curr_instance->debugfs_inode = file_dentry->d_inode; + } + + mutex_unlock(&lock); + + return 0; +} +/* + * Must be executed after all instances have been created, hence the + * late_initcall. + */ +late_initcall(init_debugfs); + +#endif /* #ifdef CONFIG_DEBUG_FS */ |