On 2025/12/23 10:00, Hongbo Li wrote:
From: Hongzhen Luo <[email protected]>
This patch implements the .fadvise interface for page cache share.
Similar to overlayfs, it drops those clean, unused pages through
vfs_fadvise().
Reviewed-by: Gao Xiang <[email protected]>
Signed-off-by: Hongzhen Luo <[email protected]>
Signed-off-by: Hongbo Li <[email protected]>
This should be sent out together within the series next time.
---
fs/erofs/ishare.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/fs/erofs/ishare.c b/fs/erofs/ishare.c
index 269b53b3ed79..d7231953cba2 100644
--- a/fs/erofs/ishare.c
+++ b/fs/erofs/ishare.c
@@ -187,6 +187,16 @@ static int erofs_ishare_mmap(struct file *file, struct
vm_area_struct *vma)
return generic_file_readonly_mmap(file, vma);
}
+static int erofs_ishare_fadvise(struct file *file, loff_t offset,
+ loff_t len, int advice)
+{
+ struct file *realfile = file->private_data;
+
+ if (!realfile)
+ return -EINVAL;
BTW, when file->private_data == NULL here?
I think it can only happen if buggy, so just:
return vfs_fadvise((struct file *)file->private_data,
offset, len, advice);
Thanks,
Gao Xiang
+ return vfs_fadvise(realfile, offset, len, advice);
+}
+
const struct file_operations erofs_ishare_fops = {
.open = erofs_ishare_file_open,
.llseek = generic_file_llseek,
@@ -195,6 +205,7 @@ const struct file_operations erofs_ishare_fops = {
.release = erofs_ishare_file_release,
.get_unmapped_area = thp_get_unmapped_area,
.splice_read = filemap_splice_read,
+ .fadvise = erofs_ishare_fadvise,
};
/*
