ascend: sharepool: calculate the correct offset of the address which is customized

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI
CVE: NA

-------------------------------------------------

In AI training scene, the sp area range is specified by host user, it
will result in an address offset calculation error, so fix it to avoid
the offset overflow.

If the user needs to specify the sp area range, the user should reserve
the virtual memory space by themselvs, otherwise the sp area would be
used for none share pool process.
Signed-off-by: NDing Tianhong <dingtianhong@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

mm/share_pool.c

@@ -214,7 +214,7 @@ struct sp_area {
 };
 static DEFINE_SPINLOCK(sp_area_lock);
 static struct rb_root sp_area_root = RB_ROOT;
-static bool host_svm_sp_enable = false;
+static bool sp_area_customized;
 
 static unsigned long spa_size(struct sp_area *spa)
 {
@@ -409,6 +409,18 @@ int sp_group_id_by_pid(int pid)
 }
 EXPORT_SYMBOL_GPL(sp_group_id_by_pid);
 
+static loff_t addr_to_offset(unsigned long addr, struct sp_area *spa)
+{
+	if (sp_area_customized == false)
+		return (loff_t)(addr - MMAP_SHARE_POOL_START);
+
+	if (spa && spa->spg)
+		return (loff_t)(addr - spa->spg->dvpp_va_start);
+
+	pr_err("share pool: the addr is not belong to share pool range\n");
+	return addr;
+}
+
 /* the caller must hold sp_group_sem */
 static struct sp_group *find_or_alloc_sp_group(int spg_id)
 {
@@ -812,7 +824,7 @@ static struct sp_area *sp_alloc_area(unsigned long size, unsigned long flags,
 	unsigned long size_align = PMD_ALIGN(size); /* va aligned to 2M */
 
 	if ((flags & SP_DVPP)) {
-		if (host_svm_sp_enable == false) {
+		if (sp_area_customized == false) {
 			vstart = MMAP_SHARE_POOL_16G_START;
 			vend = MMAP_SHARE_POOL_16G_START + MMAP_SHARE_POOL_16G_SIZE;
 		} else {
@@ -1204,7 +1216,7 @@ int sp_free(unsigned long addr)
 
 	/* Free the memory of the backing shmem or hugetlbfs */
 	mode = FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE;
-	offset = addr - MMAP_SHARE_POOL_START;
+	offset = addr_to_offset(addr, spa);
 	ret = vfs_fallocate(spa_file(spa), mode, offset, spa_size(spa));
 	if (ret)
 		pr_err("share pool: sp free fallocate failed: %d\n", ret);
@@ -1241,7 +1253,7 @@ static unsigned long sp_mmap(struct mm_struct *mm, struct file *file,
 	unsigned long flags = MAP_FIXED | MAP_SHARED | MAP_POPULATE |
 			      MAP_SHARE_POOL;
 	unsigned long vm_flags = VM_NORESERVE | VM_SHARE_POOL | VM_DONTCOPY;
-	unsigned long pgoff = (addr - MMAP_SHARE_POOL_START) >> PAGE_SHIFT;
+	unsigned long pgoff = addr_to_offset(addr, spa) >> PAGE_SHIFT;
 
 	/* Mark the mapped region to be locked. After the MAP_LOCKED is enable,
 	 * multiple tasks will preempt resources, causing performance loss.
@@ -1439,7 +1451,7 @@ void *sp_alloc(unsigned long size, unsigned long sp_flags, int spg_id)
 			p = ERR_PTR(ret);
 
 			mode = FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE;
-			offset = sp_addr - MMAP_SHARE_POOL_START;
+			offset = addr_to_offset(sp_addr, spa);
 
 			ret = vfs_fallocate(spa_file(spa), mode, offset, spa_size(spa));
 			if (ret)
@@ -2457,7 +2469,7 @@ bool sp_config_dvpp_range(size_t start, size_t size, int device_id, int pid)
 	spg->dvpp_multi_spaces = true;
 	up_write(&spg->rw_lock);
 
-	host_svm_sp_enable = true;
+	sp_area_customized = true;
 
 	sp_group_drop(spg);
 	return true;
@@ -2467,10 +2479,20 @@ EXPORT_SYMBOL_GPL(sp_config_dvpp_range);
 /* Check whether the address belongs to the share pool. */
 bool is_sharepool_addr(unsigned long addr)
 {
-	if (host_svm_sp_enable == false)
-		return addr >= MMAP_SHARE_POOL_START && addr < (MMAP_SHARE_POOL_16G_START + MMAP_SHARE_POOL_16G_SIZE);
+	struct sp_area *spa;
+	bool ret = false;
+
+	if (sp_area_customized == false)
+		return addr >= MMAP_SHARE_POOL_START &&
+		       addr < (MMAP_SHARE_POOL_16G_START + MMAP_SHARE_POOL_16G_SIZE);
+
+	spa = __find_sp_area(addr);
+	if (spa && spa->spg)
+		ret = addr >= spa->spg->dvpp_va_start &&
+		      addr < (spa->spg->dvpp_va_start + spa->spg->dvpp_size);
 
-	return addr >= MMAP_SHARE_POOL_START && addr < MMAP_SHARE_POOL_END;
+	__sp_area_drop(spa);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(is_sharepool_addr);