Pull fsnotify reverts from Jan Kara: "Syzbot has found out that fsnotify HSM events generated on page fault can be generated while we already hold freeze protection for the filesystem (when you do buffered write from a buffer which is mmapped file on the same filesystem) which violates expectations for HSM events and could lead to deadlocks of HSM clients with filesystem freezing. Since it's quite late in the cycle we've decided to revert changes implementing HSM events on page fault for now and instead just generate one event for the whole range on mmap(2) so that HSM client can fetch the data at that moment" * tag 'fsnotify_for_v6.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: Revert "fanotify: disable readahead if we have pre-content watches" Revert "mm: don't allow huge faults for files with pre content watches" Revert "fsnotify: generate pre-content permission event on page fault" Revert "xfs: add pre-content fsnotify hook for DAX faults" Revert "ext4: add pre-content fsnotify hook for DAX faults" fsnotify: add pre-content hooks on mmap()
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| @@ -170,6 +170,21 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask, · 169 unmodified lines | ||
| 170 | 170 | return fsnotify_path(&file->f_path, FS_ACCESS_PERM); |
| 171 | 171 | } |
| 172 | 172 | |
| 173 | +/* | |
| 174 | + * fsnotify_mmap_perm - permission hook before mmap of file range | |
| 175 | + */ | |
| 176 | +static inline int fsnotify_mmap_perm(struct file *file, int prot, | |
| 177 | + const loff_t off, size_t len) | |
| 178 | +{ | |
| 179 | + /* | |
| 180 | + * mmap() generates only pre-content events. | |
| 181 | + */ | |
| 182 | + if (!file || likely(!FMODE_FSNOTIFY_HSM(file->f_mode))) | |
| 183 | + return 0; | |
| 184 | + | |
| 185 | + return fsnotify_pre_content(&file->f_path, &off, len); | |
| 186 | +} | |
| 187 | + | |
| 173 | 188 | /* |
| 174 | 189 | * fsnotify_truncate_perm - permission hook before file truncate |
| 175 | 190 | */ |
| @@ -223,6 +238,12 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask, · 47 unmodified lines | ||
| 223 | 238 | return 0; |
| 224 | 239 | } |
| 225 | 240 | |
| 241 | +static inline int fsnotify_mmap_perm(struct file *file, int prot, | |
| 242 | + const loff_t off, size_t len) | |
| 243 | +{ | |
| 244 | + return 0; | |
| 245 | +} | |
| 246 | + | |
| 226 | 247 | static inline int fsnotify_truncate_perm(const struct path *path, loff_t length) |
| 227 | 248 | { |
| 228 | 249 | return 0; |
| @@ -3420,7 +3420,6 @@ extern vm_fault_t filemap_fault(struct vm_fault *vmf); · 3419 unmodified lines | ||
| 3420 | 3420 | extern vm_fault_t filemap_map_pages(struct vm_fault *vmf, |
| 3421 | 3421 | pgoff_t start_pgoff, pgoff_t end_pgoff); |
| 3422 | 3422 | extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf); |
| 3423 | −extern vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf); | |
| 3424 | 3423 | |
| 3425 | 3424 | extern unsigned long stack_guard_gap; |
| 3426 | 3425 | /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ |