erofs fixes for 7.4-rc1

Hi Linus,

Could you consider these extra fixes for 7.4-rc1?

These patches address several new reported issues related to page cache sharing, the new superblock_share feature, and recent metadata path changes for file-backed mounts.

All commits have been in linux-next, and no potential merge conflicts have been observed.

Thanks,
Gao Xiang

The following changes since commit 1137aa577a35e2684e8046c3e53f920e79c7cc60:

erofs: enable iomap for file-backed mounts on unencoded inodes (2026-10-17 17:29:36 +0200)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git tags/erofs-for-7.4-rc1-2

for you to fetch changes up to 209108a5456171ab430e25b54b2dfe083455bfb6:

erofs: drop unnecessary .read_folio() checks for file-backed mounts (2026-10-27 09:15:19 +0100)

----------------------------------------------------------------
Changes since last update:

- Hold real inodes to fix mmap usage with page cache sharing

- Fix metadata reads at the end of file-backed images with sub-page block sizes

- Ensure disallowing superblock_share when device= is specified

- Drop unnecessary .read_folio() checks for file-backed mounts to allow tmpfs as a backing fs

----------------------------------------------------------------
Gao Xiang (2):
erofs: hold real inodes for shared files
erofs: drop unnecessary .read_folio() checks for file-backed mounts

Hengyu Liang (1):
erofs: fix metadata reads at the end of file-backed images

Zhan Xusheng (1):
erofs: fix disallowing superblock_share if device= is set

 fs/erofs/fileio.c | 18 +++++++++++++++---
 fs/erofs/ishare.c | 43 ++++++++++++++++++++++++++++++-------------
 fs/erofs/super.c  |  9 ++++-----
 3 files changed, 49 insertions(+), 21 deletions(-)