sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

fs/tmpfs: add munmap interface for tmpfs file map

Browse Source 
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
This commit is contained in:
dongjiuzhu1 2023-05-09 22:54:45 +08:00 committed by Xiang Xiao
parent 9d67c7b6ac
commit e4739ab575
1 changed files with 46 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
fs/tmpfs/fs_tmpfs.c
View File

@ -1643,6 +1643,49 @@ static off_t tmpfs_seek(FAR struct file *filep, off_t offset, int whence)
return position;
}
static int tmpfs_unmap(FAR struct task_group_s *group,
FAR struct mm_map_entry_s *entry,
FAR void *start, size_t length)
{
FAR struct file *filep = entry->priv.p;
off_t offset;
int ret;
offset = (uintptr_t)start - (uintptr_t)entry->vaddr;
if (offset + length < entry->length)
{
ferr("ERROR: Cannot umap without unmapping to the end\n");
return -ENOSYS;
}
/* Okay.. the region is being unmapped to the end. Make sure the length
* indicates that.
*/
length = entry->length - offset;
/* Are we unmapping the entire region (offset == 0)? */
if (length >= entry->length)
{
/* Then remove the mapping from the list */
ret = mm_map_remove(get_group_mm(group), entry);
}
/* No.. We have been asked to "unmap' only a portion of the memory
* (offset > 0).
*/
else
{
entry->length = length;
ret = tmpfs_mmap(filep, entry);
}
return ret;
}
static int tmpfs_mmap(FAR struct file *filep, FAR struct mm_map_entry_s *map)
{
FAR struct tmpfs_file_s *tfo;
@ -1660,7 +1703,9 @@ static int tmpfs_mmap(FAR struct file *filep, FAR struct mm_map_entry_s *map)
map->length && map->offset + map->length <= tfo->tfo_size)
{
map->vaddr = tfo->tfo_data + map->offset;
ret = OK;
map->priv.p = filep;
map->munmap = tmpfs_unmap;
ret = mm_map_add(get_current_mm(), map);
}
return ret;