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().
Signed-off-by: Hongzhen Luo <[email protected]> [hongbo: forward port, minor cleanup] Signed-off-by: Hongbo Li <[email protected]> --- fs/erofs/ishare.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/erofs/ishare.c b/fs/erofs/ishare.c index 73432b13bf75..b067f0e02d6c 100644 --- a/fs/erofs/ishare.c +++ b/fs/erofs/ishare.c @@ -228,6 +228,16 @@ static int erofs_ishare_mmap(struct file *file, struct vm_area_struct *vma) return generic_file_readonly_mmap(file, vma); } +static int erofs_ishare_fadvice(struct file *file, loff_t offset, + loff_t len, int advice) +{ + struct file *realfile = file->private_data; + + if (!realfile) + return -EINVAL; + return vfs_fadvise(realfile, offset, len, advice); +} + const struct file_operations erofs_ishare_fops = { .open = erofs_ishare_file_open, .llseek = generic_file_llseek, @@ -236,6 +246,7 @@ 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_fadvice, }; void erofs_read_begin(struct erofs_read_ctx *rdctx) -- 2.22.0
