From 066e053fe208a3b83ee89dc5a192146add688861 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 12 Mar 2025 08:38:47 +0100 Subject: fsnotify: add pre-content hooks on mmap() Pre-content hooks in page faults introduces potential deadlock of HSM handler in userspace with filesystem freezing. The requirement with pre-content event is that for every accessed file range an event covering at least this range will be generated at least once before the file data is accesses. In preparation to disabling pre-content event hooks on page faults, add pre-content hooks at mmap() variants for the entire mmaped range, so HSM can fill content when user requests to map a portion of the file. Note that exec() variant also calls vm_mmap_pgoff() internally to map code sections, so pre-content hooks are also generated in this case. Link: https://lore.kernel.org/linux-fsdevel/7ehxrhbvehlrjwvrduoxsao5k3x4aw275patsb3krkwuq573yv@o2hskrfawbnc/ Suggested-by: Josef Bacik Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Link: https://patch.msgid.link/20250312073852.2123409-2-amir73il@gmail.com --- mm/util.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'mm') diff --git a/mm/util.c b/mm/util.c index b6b9684a1438..8c965474d329 100644 --- a/mm/util.c +++ b/mm/util.c @@ -23,6 +23,7 @@ #include #include #include +#include #include @@ -569,6 +570,8 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr, LIST_HEAD(uf); ret = security_mmap_file(file, prot, flag); + if (!ret) + ret = fsnotify_mmap_perm(file, prot, pgoff >> PAGE_SHIFT, len); if (!ret) { if (mmap_write_lock_killable(mm)) return -EINTR; -- cgit