Commit 9eec1d897139("squashfs: provide backing_dev_info in order to disable read-ahead") mitigates the performance drop issue for squashfs by closing readahead for it. This series implements readahead callback for squashfs. The previous discussions are in [1] and [2]. [1] https://lore.kernel.org/all/CAJMQK-g9G6KQmH-V=BRGX0swZji9Wxe_2c7ht-MMAapdFy2pXw@xxxxxxxxxxxxxx/T/ [2] https://lore.kernel.org/linux-mm/Yn5Yij9pRPCzDozt@xxxxxxxxxxxxxxxxxxxx/t/#m4af4473b94f98a4996cb11756b633a07e5e059d1 This version is based on next-20220610 and the following series: "Squashfs: handle missing pages decompressing into page cache" [3]. This version is a refresh of ca1505bf4805 ("squashfs: implement readahead") and 9d58b94aa73a ("squashfs: always build "file direct" version of page actor"). There's no change in 4af2bd190a5b7 (Revert "squashfs: provide backing_dev_info in order to disable read-ahead"), but it's carried in this version too for consistency. [3] https://patchwork.kernel.org/project/linux-mm/cover/20220611032133.5743-1-phillip@xxxxxxxxxxxxxxx/ Hsin-Yi Wang (2): Revert "squashfs: provide backing_dev_info in order to disable read-ahead" squashfs: implement readahead Phillip Lougher (1): squashfs: always build "file direct" version of page actor fs/squashfs/Makefile | 4 +- fs/squashfs/file.c | 92 +++++++++++++++++++++++++++++++++++++++- fs/squashfs/page_actor.h | 46 -------------------- fs/squashfs/super.c | 33 -------------- 4 files changed, 93 insertions(+), 82 deletions(-) -- 2.36.1.476.g0c4daa206d-goog