linux/fs
Nicolas Pitre eddcd97659 cramfs: add mmap support
When cramfs in physical memory is used then we have the opportunity
to map files directly from ROM, directly into user space, saving on
RAM usage. This gives us Execute-In-Place (XIP) support.

For a file to be mmap()-able, the map area has to correspond to a range
of uncompressed and contiguous blocks, and in the MMU case it also has
to be page aligned. A version of mkcramfs with appropriate support is
necessary to create such a filesystem image.

In the MMU case it may happen for a vma structure to extend beyond the
actual file size. This is notably the case in binfmt_elf.c:elf_map().
Or the file's last block is shared with other files and cannot be mapped
as is. Rather than refusing to mmap it, we do a "mixed" map and let the
regular fault handler populate the unmapped area with RAM-backed pages.
In practice the unmapped area is seldom accessed so page faults might
never occur before this area is discarded.

In the non-MMU case it is the get_unmapped_area method that is responsible
for providing the address where the actual data can be found. No mapping
is necessary of course.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-15 00:47:22 -04:00
..
9p Merge branch 'akpm' (patches from Andrew) 2017-09-06 20:49:49 -07:00
adfs
affs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
afs Merge branch 'akpm' (patches from Andrew) 2017-09-06 20:49:49 -07:00
autofs4 Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
befs VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
bfs bfs: fix sanity checks for empty files 2017-07-12 16:26:00 -07:00
btrfs Merge branch 'for-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux 2017-10-06 09:03:08 -07:00
cachefiles VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
ceph ceph: fix __choose_mds() for LSSNAP request 2017-10-02 16:18:16 +02:00
cifs SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags 2017-09-22 19:47:17 -05:00
coda fs: fix kernel_read prototype 2017-09-04 19:05:15 -04:00
configfs configfs: Introduce config_item_get_unless_zero() 2017-06-12 13:20:20 +02:00
cramfs cramfs: add mmap support 2017-10-15 00:47:22 -04:00
crypto block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
debugfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 12:00:42 -07:00
devpts pty: Repair TIOCGPTPEER 2017-08-24 13:23:03 -07:00
dlm File locking related changes for v4.14 2017-09-06 13:43:26 -07:00
ecryptfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
efivarfs VFS: Kill off s_options and helpers 2017-07-11 06:09:21 -04:00
efs VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
exofs Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block 2017-09-07 11:59:42 -07:00
exportfs
ext2 Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ext4 Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 19:29:55 -07:00
f2fs for-f2fs-4.14 2017-09-12 20:05:58 -07:00
fat Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
freevxfs
fscache fscache: fix fscache_objlist_show format processing 2017-09-13 18:53:15 -07:00
fuse Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse 2017-09-13 10:10:19 -07:00
gfs2 GFS2: Fix an old regression in GFS2's debugfs interface 2017-09-25 15:41:56 -07:00
hfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
hfsplus Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
hostfs fs: convert a pile of fsync routines to errseq_t based reporting 2017-08-01 08:39:29 -04:00
hpfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
hugetlbfs lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
isofs isofs: fix build regression 2017-09-18 12:24:26 +02:00
jbd2 Writeback error handling fixes (pile #2) 2017-07-07 19:38:17 -07:00
jffs2 Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
jfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
kernfs Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block 2017-09-07 11:59:42 -07:00
lockd NFS client updates for Linux 4.14 2017-09-11 22:01:44 -07:00
minix VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
ncpfs fs: convert a pile of fsync routines to errseq_t based reporting 2017-08-01 08:39:29 -04:00
nfs NFS client bugfixes for Linux 4.14 2017-09-14 20:04:32 -07:00
nfs_common
nfsd More RDMA work and some op-structure constification from Chuck Lever, 2017-09-09 13:31:49 -07:00
nilfs2 Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
nls
notify fsnotify: make dnotify_fsnotify_ops const 2017-08-30 16:02:48 +02:00
ntfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ocfs2 Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
omfs omfs: Implement show_options 2017-07-06 03:31:46 -04:00
openpromfs
orangefs orangefs: Adjust three checks for null pointers 2017-09-14 14:58:31 -04:00
overlayfs ovl: fix regression caused by exclusive upper/work dir protection 2017-10-05 15:53:18 +02:00
proc sched/debug: Add explicit TASK_PARKED printing 2017-09-29 11:02:57 +02:00
pstore Revert "pstore: Honor dmesg_restrict sysctl on dmesg dumps" 2017-08-17 16:29:19 -07:00
qnx4
qnx6
quota quota: Fix quota corruption with generic/232 test 2017-09-27 11:33:47 +02:00
ramfs mm: make pagevec_lookup() update index 2017-09-06 17:27:26 -07:00
reiserfs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
romfs
squashfs squashfs: Add zstd support 2017-09-08 19:33:25 -07:00
sysfs
sysv VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
tracefs VFS: Don't use save/replace_mount_options if not using generic_show_options 2017-07-06 03:31:46 -04:00
ubifs Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
udf Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ufs VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
xfs xfs: handle racy AIO in xfs_reflink_end_cow 2017-10-03 21:27:55 -07:00
Kconfig fs/Kconfig: kill CONFIG_PERCPU_RWSEM some more 2017-07-12 16:26:00 -07:00
Kconfig.binfmt
Makefile
aio.c Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 19:29:55 -07:00
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c fs: fix kernel_read prototype 2017-09-04 19:05:15 -04:00
binfmt_elf.c Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
binfmt_elf_fdpic.c Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
binfmt_em86.c
binfmt_flat.c Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
binfmt_misc.c exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array 2017-10-03 17:54:25 -07:00
binfmt_script.c exec: load_script: kill the onstack interp[BINPRM_BUF_SIZE] array 2017-10-03 17:54:25 -07:00
block_dev.c Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 19:29:55 -07:00
buffer.c Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block 2017-09-07 11:59:42 -07:00
char_dev.c char_dev: order /proc/devices by major number 2017-07-17 15:28:50 +02:00
compat.c
compat_binfmt_elf.c
compat_ioctl.c media: get rid of removed DMX_GET_CAPS and DMX_SET_SOURCE leftovers 2017-09-05 08:25:07 -04:00
coredump.c mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
dax.c - Some request-based DM core and DM multipath fixes and cleanups 2017-09-14 13:43:16 -07:00
dcache.c Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 12:00:42 -07:00
dcookies.c
direct-io.c fs: Fix page cache inconsistency when mixing buffered and AIO DIO 2017-09-25 08:56:05 -06:00
drop_caches.c
eventfd.c There has been a fair amount of activity in the docs tree this time 2017-07-03 21:13:25 -07:00
eventpoll.c fs/epoll: use faster rb_first_cached() 2017-09-08 18:26:49 -07:00
exec.c exec: load_script: kill the onstack interp[BINPRM_BUF_SIZE] array 2017-10-03 17:54:25 -07:00
fcntl.c fcntl: Don't set si_code to SI_SIGIO when sig == SIGPOLL 2017-09-18 22:51:14 -05:00
fhandle.c
file.c fs/file.c: replace alloc_fdmem() with kvmalloc() alternative 2017-07-06 16:24:30 -07:00
file_table.c fput: Don't reinvent the wheel but use existing llist API 2017-08-28 00:50:23 -04:00
filesystems.c Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 12:00:42 -07:00
fs-writeback.c writeback: rework wb_[dec|inc]_stat family of functions 2017-07-12 16:26:05 -07:00
fs_pin.c sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming 2017-06-20 12:19:14 +02:00
fs_struct.c
inode.c Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2017-09-13 09:11:44 -07:00
internal.h Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2017-09-13 09:11:44 -07:00
ioctl.c
iomap.c Changes since last update: 2017-09-28 13:27:23 -07:00
libfs.c fs: convert __generic_file_fsync to use errseq_t based reporting 2017-07-06 07:02:29 -04:00
locks.c locks: restore a warn for leaked locks on close 2017-07-21 13:57:31 -04:00
mbcache.c ext4: xattr inode deduplication 2017-06-22 11:44:55 -04:00
mount.h Now that IPC and other changes have landed, enable manual markings for 2017-07-19 08:55:18 -07:00
mpage.c block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
namei.c Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
namespace.c ovl: fix may_write_real() for overlayfs directories 2017-10-05 15:53:18 +02:00
no-block.c
nsfs.c VFS: Provide empty name qstr 2017-07-06 03:27:09 -04:00
open.c ovl: don't allow writing ioctl on lower layer 2017-09-05 12:53:12 +02:00
pipe.c VFS: Provide empty name qstr 2017-07-06 03:27:09 -04:00
pnode.c mnt: Make propagate_umount less slow for overlapping mount propagation trees 2017-05-23 08:41:17 -05:00
pnode.h
posix_acl.c
proc_namespace.c VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) 2017-07-17 08:45:34 +01:00
read_write.c vfs: Return -ENXIO for negative SEEK_HOLE / SEEK_DATA offsets 2017-09-26 13:46:06 -07:00
readdir.c
select.c fs/select: Fix memory corruption in compat_get_fd_set() 2017-08-28 16:09:19 -07:00
seq_file.c mm: introduce kv[mz]alloc helpers 2017-05-08 17:15:12 -07:00
signalfd.c signal: Remove kernel interal si_code magic 2017-07-24 14:30:28 -05:00
splice.c fs: move kernel_write to fs/read_write.c 2017-09-04 19:05:15 -04:00
stack.c
stat.c fs: Provide __inode_get_bytes() 2017-08-17 22:06:03 +02:00
statfs.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-08 10:50:54 -07:00
super.c Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
sync.c Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
timerfd.c timerfd: Use get_itimerspec64() and put_itimerspec64() 2017-06-30 04:14:38 -04:00
userfaultfd.c userfaultfd: non-cooperative: fix fork use after free 2017-10-03 17:54:25 -07:00
utimes.c utimes: Make utimes y2038 safe 2017-09-03 20:24:30 -04:00
xattr.c lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-04 18:03:15 +11:00