[<prev] [next>] [day] [month] [year] [list]
Message-ID: <20241011065128.2097377-1-hsiangkao@linux.alibaba.com>
Date: Fri, 11 Oct 2024 14:51:28 +0800
From: Gao Xiang <hsiangkao@...ux.alibaba.com>
To: linux-erofs@...ts.ozlabs.org
Cc: LKML <linux-kernel@...r.kernel.org>,
Gao Xiang <hsiangkao@...ux.alibaba.com>
Subject: [PATCH] erofs: add SEEK_{DATA,HOLE} support
Many userspace programs (including erofs-utils itself) uses SEEK_DATA /
SEEK_HOLE to parse hole extents in addition to FIEMAP.
Signed-off-by: Gao Xiang <hsiangkao@...ux.alibaba.com>
---
fs/erofs/data.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index 61debd799cf9..6355866220ff 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -473,8 +473,32 @@ static int erofs_file_mmap(struct file *file, struct vm_area_struct *vma)
#define erofs_file_mmap generic_file_readonly_mmap
#endif
+static loff_t erofs_file_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct inode *inode = file->f_mapping->host;
+ const struct iomap_ops *ops = &erofs_iomap_ops;
+
+ if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
+#ifdef CONFIG_EROFS_FS_ZIP
+ ops = &z_erofs_iomap_report_ops;
+#else
+ return generic_file_llseek(file, offset, whence);
+#endif
+
+ if (whence == SEEK_HOLE)
+ offset = iomap_seek_hole(inode, offset, ops);
+ else if (whence == SEEK_DATA)
+ offset = iomap_seek_data(inode, offset, ops);
+ else
+ return generic_file_llseek(file, offset, whence);
+
+ if (offset < 0)
+ return offset;
+ return vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
+}
+
const struct file_operations erofs_file_fops = {
- .llseek = generic_file_llseek,
+ .llseek = erofs_file_llseek,
.read_iter = erofs_file_read_iter,
.mmap = erofs_file_mmap,
.get_unmapped_area = thp_get_unmapped_area,
--
2.43.5
Powered by blists - more mailing lists