diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/Locking | 14 | ||||
| -rw-r--r-- | Documentation/filesystems/dax.txt | 6 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 9 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 11 |
4 files changed, 33 insertions, 7 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 75eea7ce3d7c..5a7386e38e2d 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -195,7 +195,9 @@ prototypes: int (*releasepage) (struct page *, int); void (*freepage)(struct page *); int (*direct_IO)(struct kiocb *, struct iov_iter *iter); + bool (*isolate_page) (struct page *, isolate_mode_t); int (*migratepage)(struct address_space *, struct page *, struct page *); + void (*putback_page) (struct page *); int (*launder_page)(struct page *); int (*is_partially_uptodate)(struct page *, unsigned long, unsigned long); int (*error_remove_page)(struct address_space *, struct page *); @@ -219,7 +221,9 @@ invalidatepage: yes releasepage: yes freepage: yes direct_IO: +isolate_page: yes migratepage: yes (both) +putback_page: yes launder_page: yes is_partially_uptodate: yes error_remove_page: yes @@ -544,13 +548,13 @@ subsequent truncate), and then return with VM_FAULT_LOCKED, and the page locked. The VM will unlock the page. ->map_pages() is called when VM asks to map easy accessible pages. -Filesystem should find and map pages associated with offsets from "pgoff" -till "max_pgoff". ->map_pages() is called with page table locked and must +Filesystem should find and map pages associated with offsets from "start_pgoff" +till "end_pgoff". ->map_pages() is called with page table locked and must not block. If it's not possible to reach a page without blocking, filesystem should skip it. Filesystem should use do_set_pte() to setup -page table entry. Pointer to entry associated with offset "pgoff" is -passed in "pte" field in vm_fault structure. Pointers to entries for other -offsets should be calculated relative to "pte". +page table entry. Pointer to entry associated with the page is passed in +"pte" field in fault_env structure. Pointers to entries for other offsets +should be calculated relative to "pte". ->page_mkwrite() is called when a previously read-only pte is about to become writeable. The filesystem again must ensure that there are diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt index ce4587d257d2..0c16a22521a8 100644 --- a/Documentation/filesystems/dax.txt +++ b/Documentation/filesystems/dax.txt @@ -49,6 +49,7 @@ These block devices may be used for inspiration: - axonram: Axon DDR2 device driver - brd: RAM backed block device driver - dcssblk: s390 dcss block device driver +- pmem: NVDIMM persistent memory driver Implementation Tips for Filesystem Writers @@ -75,8 +76,9 @@ calls to get_block() (for example by a page-fault racing with a read() or a write()) work correctly. These filesystems may be used for inspiration: -- ext2: the second extended filesystem, see Documentation/filesystems/ext2.txt -- ext4: the fourth extended filesystem, see Documentation/filesystems/ext4.txt +- ext2: see Documentation/filesystems/ext2.txt +- ext4: see Documentation/filesystems/ext4.txt +- xfs: see Documentation/filesystems/xfs.txt Handling Media Errors diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 5b61eeae3f6e..68080ad6a75e 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -436,6 +436,7 @@ Private_Dirty: 0 kB Referenced: 892 kB Anonymous: 0 kB AnonHugePages: 0 kB +ShmemPmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 0 kB @@ -464,6 +465,8 @@ accessed. a mapping associated with a file may contain anonymous pages: when MAP_PRIVATE and a page is modified, the file page is replaced by a private anonymous copy. "AnonHugePages" shows the ammount of memory backed by transparent hugepage. +"ShmemPmdMapped" shows the ammount of shared (shmem/tmpfs) memory backed by +huge pages. "Shared_Hugetlb" and "Private_Hugetlb" show the ammounts of memory backed by hugetlbfs page which is *not* counted in "RSS" or "PSS" field for historical reasons. And these are not included in {Shared,Private}_{Clean,Dirty} field. @@ -868,6 +871,9 @@ VmallocTotal: 112216 kB VmallocUsed: 428 kB VmallocChunk: 111088 kB AnonHugePages: 49152 kB +ShmemHugePages: 0 kB +ShmemPmdMapped: 0 kB + MemTotal: Total usable ram (i.e. physical ram minus a few reserved bits and the kernel binary code) @@ -912,6 +918,9 @@ MemAvailable: An estimate of how much memory is available for starting new AnonHugePages: Non-file backed huge pages mapped into userspace page tables Mapped: files which have been mmaped, such as libraries Shmem: Total memory used by shared memory (shmem) and tmpfs +ShmemHugePages: Memory used by shared memory (shmem) and tmpfs allocated + with huge pages +ShmemPmdMapped: Shared memory mapped into userspace with huge pages Slab: in-kernel data structures cache SReclaimable: Part of Slab, that might be reclaimed, such as caches SUnreclaim: Part of Slab, that cannot be reclaimed on memory pressure diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index c61a223ef3ff..900360cbcdae 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -592,9 +592,14 @@ struct address_space_operations { int (*releasepage) (struct page *, int); void (*freepage)(struct page *); ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter); + /* isolate a page for migration */ + bool (*isolate_page) (struct page *, isolate_mode_t); /* migrate the contents of a page to the specified target */ int (*migratepage) (struct page *, struct page *); + /* put migration-failed page back to right list */ + void (*putback_page) (struct page *); int (*launder_page) (struct page *); + int (*is_partially_uptodate) (struct page *, unsigned long, unsigned long); void (*is_dirty_writeback) (struct page *, bool *, bool *); @@ -747,6 +752,10 @@ struct address_space_operations { and transfer data directly between the storage and the application's address space. + isolate_page: Called by the VM when isolating a movable non-lru page. + If page is successfully isolated, VM marks the page as PG_isolated + via __SetPageIsolated. + migrate_page: This is used to compact the physical memory usage. If the VM wants to relocate a page (maybe off a memory card that is signalling imminent failure) it will pass a new page @@ -754,6 +763,8 @@ struct address_space_operations { transfer any private data across and update any references that it has to the page. + putback_page: Called by the VM when isolated page's migration fails. + launder_page: Called before freeing a page - it writes back the dirty page. To prevent redirtying the page, it is kept locked during the whole operation. |