diff options
Diffstat (limited to 'drivers/sipc/smem.c')
| -rw-r--r-- | drivers/sipc/smem.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/sipc/smem.c b/drivers/sipc/smem.c new file mode 100644 index 00000000..550f4411 --- /dev/null +++ b/drivers/sipc/smem.c @@ -0,0 +1,180 @@ +/* + * Copyright (C) 2012 Spreadtrum Communications 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/kernel.h> +#include <linux/module.h> +#include <linux/genalloc.h> +#include <linux/mm.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/sched.h> + +#include <linux/sipc.h> + +struct smem_pool { + struct list_head smem_head; + spinlock_t lock; + + uint32_t addr; + uint32_t size; + atomic_t used; + + struct gen_pool *gen; +}; + +struct smem_record { + struct list_head smem_list; + struct task_struct *task; + uint32_t size; + uint32_t addr; +}; + +static struct smem_pool mem_pool; + +int smem_init(uint32_t addr, uint32_t size) +{ + struct smem_pool *spool = &mem_pool; + + spool->addr = addr; + spool->size = PAGE_ALIGN(size); + atomic_set(&spool->used, 0); + spin_lock_init(&spool->lock); + INIT_LIST_HEAD(&spool->smem_head); + + /* allocator block size is times of pages */ + spool->gen = gen_pool_create(PAGE_SHIFT, -1); + if (!spool->gen) { + printk(KERN_ERR "Failed to create smem gen pool!\n"); + return -1; + } + + if (gen_pool_add(spool->gen, spool->addr, spool->size, -1) != 0) { + printk(KERN_ERR "Failed to add smem gen pool!\n"); + return -1; + } + + return 0; +} + +/* ****************************************************************** */ + +uint32_t smem_alloc(uint32_t size) +{ + struct smem_pool *spool = &mem_pool; + struct smem_record *recd; + unsigned long flags; + uint32_t addr; + + recd = kzalloc(sizeof(struct smem_record), GFP_KERNEL); + if (!recd) { + printk(KERN_ERR "failed to alloc smem record\n"); + addr = 0; + goto error; + } + + size = PAGE_ALIGN(size); + addr = gen_pool_alloc(spool->gen, size); + if (!addr) { + printk(KERN_ERR "failed to alloc smem from gen pool\n"); + kfree(recd); + goto error; + } + + /* record smem alloc info */ + atomic_add(size, &spool->used); + recd->size = size; + recd->task = current; + recd->addr = addr; + spin_lock_irqsave(&spool->lock, flags); + list_add_tail(&recd->smem_list, &spool->smem_head); + spin_unlock_irqrestore(&spool->lock, flags); + +error: + return addr; +} + +void smem_free(uint32_t addr, uint32_t size) +{ + struct smem_pool *spool = &mem_pool; + struct smem_record *recd, *next; + unsigned long flags; + + size = PAGE_ALIGN(size); + atomic_sub(size, &spool->used); + gen_pool_free(spool->gen, addr, size); + /* delete record node from list */ + spin_lock_irqsave(&spool->lock, flags); + list_for_each_entry_safe(recd, next, &spool->smem_head, smem_list) { + if (recd->addr == addr) { + list_del(&recd->smem_list); + kfree(recd); + break; + } + } + spin_unlock_irqrestore(&spool->lock, flags); +} + +#ifdef CONFIG_DEBUG_FS +static int smem_debug_show(struct seq_file *m, void *private) +{ + struct smem_pool *spool = &mem_pool; + struct smem_record *recd; + uint32_t fsize; + unsigned long flags; + + fsize = gen_pool_avail(spool->gen); + + seq_printf(m, "smem pool infomation:\n"); + seq_printf(m, "phys_addr=0x%x, total=0x%x, used=0x%x, free=0x%x\n", + spool->addr, spool->size, spool->used, fsize); + seq_printf(m, "smem record list:\n"); + + spin_lock_irqsave(&spool->lock, flags); + list_for_each_entry(recd, &spool->smem_head, smem_list) { + seq_printf(m, "task %s: pid=%u, addr=0x%x, size=0x%x\n", + recd->task->comm, recd->task->pid, recd->addr, recd->size); + } + spin_unlock_irqrestore(&spool->lock, flags); + return 0; +} + +static int smem_debug_open(struct inode *inode, struct file *file) +{ + return single_open(file, smem_debug_show, inode->i_private); +} + +static const struct file_operations smem_debug_fops = { + .open = smem_debug_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +int smem_init_debugfs(void *root) +{ + if (!root) + return -ENXIO; + debugfs_create_file("smem", S_IRUGO, (struct dentry *)root, NULL, &smem_debug_fops); + return 0; +} + +#endif //endof CONFIG_DEBUG_FS + +EXPORT_SYMBOL(smem_alloc); +EXPORT_SYMBOL(smem_free); + +MODULE_AUTHOR("Chen Gaopeng"); +MODULE_DESCRIPTION("SIPC/SMEM driver"); +MODULE_LICENSE("GPL"); |