Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Instead of keeping two levels of indirection for requests types, fold it
all into the operations. The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.
Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit e96a8a3bb6 ("UBI: Fastmap: Do not add vol if it already
exists") introduced a bug by changing the possible error codes returned
by add_vol():
- this function no longer returns NULL in case of allocation failure
but return ERR_PTR(-ENOMEM)
- when a duplicate entry in the volume RB tree is found it returns
ERR_PTR(-EEXIST) instead of ERR_PTR(-EINVAL)
Fix the tests done on add_vol() return val to match this new behavior.
Fixes: e96a8a3bb6 ("UBI: Fastmap: Do not add vol if it already exists")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
drivers/mtd/ubi/eba.c: In function ‘try_recover_peb’:
drivers/mtd/ubi/eba.c:744: warning: ‘vid_hdr’ is used uninitialized in this function
The pointer vid_hdr is indeed not initialized, leading to a crash when
it is dereferenced.
Fix this by obtaining the pointer from the VID buffer, like is done
everywhere else.
Fixes: 3291b52f9f ("UBI: introduce the VID buffer concept")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Static analysis by CoverityScan detected the ec and pnum
arguments are in the wrong order on a call to ubi_alloc_aeb.
Swap the order to fix this.
Fixes: 91f4285fe3 ("UBI: provide helpers to allocate and free aeb elements")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
* Fixes for both UBI and UBIFS
* overlayfs support (O_TMPFILE, RENAME_WHITEOUT/EXCHANGE)
* Code refactoring for the upcoming MLC support
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Merge tag 'upstream-4.9-rc1' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS updates from Richard Weinberger:
"This pull request contains:
- Fixes for both UBI and UBIFS
- overlayfs support (O_TMPFILE, RENAME_WHITEOUT/EXCHANGE)
- Code refactoring for the upcoming MLC support"
[ Ugh, we just got rid of the "rename2()" naming for the extended rename
functionality. And this re-introduces it in ubifs with the cross-
renaming and whiteout support.
But rather than do any re-organizations in the merge itself, the
naming can be cleaned up later ]
* tag 'upstream-4.9-rc1' of git://git.infradead.org/linux-ubifs: (27 commits)
UBIFS: improve function-level documentation
ubifs: fix host xattr_len when changing xattr
ubifs: Use move variable in ubifs_rename()
ubifs: Implement RENAME_EXCHANGE
ubifs: Implement RENAME_WHITEOUT
ubifs: Implement O_TMPFILE
ubi: Fix Fastmap's update_vol()
ubi: Fix races around ubi_refill_pools()
ubi: Deal with interrupted erasures in WL
UBI: introduce the VID buffer concept
UBI: hide EBA internals
UBI: provide an helper to query LEB information
UBI: provide an helper to check whether a LEB is mapped or not
UBI: add an helper to check lnum validity
UBI: simplify LEB write and atomic LEB change code
UBI: simplify recover_peb() code
UBI: move the global ech and vidh variables into struct ubi_attach_info
UBI: provide helpers to allocate and free aeb elements
UBI: fastmap: use ubi_io_{read, write}_data() instead of ubi_io_{read, write}()
UBI: fastmap: use ubi_rb_for_each_entry() in unmap_peb()
...
Usually Fastmap is free to consider every PEB in one of the pools
as newer than the existing PEB. Since PEBs in a pool are by definition
newer than everything else.
But update_vol() missed the case that a pool can contain more than
one candidate.
Cc: <stable@vger.kernel.org>
Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
When writing a new Fastmap the first thing that happens
is refilling the pools in memory.
At this stage it is possible that new PEBs from the new pools
get already claimed and written with data.
If this happens before the new Fastmap data structure hits the
flash and we face power cut the freshly written PEB will not
scanned and unnoticed.
Solve the issue by locking the pools until Fastmap is written.
Cc: <stable@vger.kernel.org>
Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger <richard@nod.at>
When Fastmap is used we can face here an -EBADMSG
since Fastmap cannot know about unmaps.
If the erasure was interrupted the PEB may show ECC
errors and UBI would go to ro-mode as it assumes
that the PEB was check during attach time, which is
not the case with Fastmap.
Cc: <stable@vger.kernel.org>
Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger <richard@nod.at>
Currently, all VID headers are allocated and freed using the
ubi_zalloc_vid_hdr() and ubi_free_vid_hdr() function. These functions
make sure to align allocation on ubi->vid_hdr_alsize and adjust the
vid_hdr pointer to match the ubi->vid_hdr_shift requirements.
This works fine, but is a bit convoluted.
Moreover, the future introduction of LEB consolidation (needed to support
MLC/TLC NANDs) will allows a VID buffer to contain more than one VID
header.
Hence the creation of a ubi_vid_io_buf struct to attach extra information
to the VID header.
We currently only store the actual pointer of the underlying buffer, but
will soon add the number of VID headers contained in the buffer.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Create a private ubi_eba_table struct to hide EBA internals and provide
helpers to allocate, destroy, copy and assing an EBA table to a volume.
Now that external EBA users are using helpers to query/modify the EBA
state we can safely change the internal representation, which will be
needed to support the LEB consolidation concept.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This is part of our attempt to hide EBA internals from other part of the
implementation in order to easily adapt it to the MLC needs.
Here we are creating an ubi_eba_leb_desc struct to hide the way we keep
track of the LEB to PEB mapping.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This is part of the process of hiding UBI EBA's internal to other part of
the UBI implementation, so that we can add new information to the EBA
table without having to patch different places in the UBI code.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
ubi_leb_valid() is here to replace the
lnum < 0 || lnum >= vol->reserved_pebs checks.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
ubi_eba_write_leb(), ubi_eba_write_leb_st() and
ubi_eba_atomic_leb_change() are using a convoluted retry/exit path.
Add the try_write_vid_and_data() function to simplify the retry logic
and make sure we have a single exit path instead of manually releasing
the resources in each error path.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
recover_peb() is using a convoluted retry/exit path. Add try_recover_peb()
to simplify the retry logic and make sure we have a single exit path
instead of manually releasing the resource in each error path.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Even if it works fine with those global variables, attaching the
temporary ech and vidh objects used during UBI scan to the
ubi_attach_info object sounds like a more future-proof option.
For example, attaching several UBI devices in parallel is prevented by
this use of global variable. And also because global variables should
be avoided in general.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This not only hides the aeb allocation internals (which is always good in
case we ever want to change the allocation system), but also helps us
factorize the initialization of some common fields (ec and pnum).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
ubi_io_{read,write}_data() are wrappers around ubi_io_{read/write}() that
are used to read/write eraseblock payload data, which is exactly what
fastmap does when calling ubi_io_{read,write}().
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Use the ubi_rb_for_each_entry() macro instead of open-coding it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Those functions are pretty much doing the same thing, except
ubi_remove_av() is putting the aeb elements attached to the volume into
the ai->erase list and the destroy_av() is freeing them.
Rework destroy_av() to handle both cases.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Volume creation/search code is duplicated in a few places (fastmap and
non fastmap code). Create some helpers to factorize the code.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
vol->usable_size is already set to ubi->leb_size - vol->data_pad. Use
vol->usable_size instead of recalculating it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
scan_pool() does not mark the PEB for scrubing when bitflips are
detected in the EC header of a free PEB (VID header region left to
0xff).
Make sure we scrub the PEB in this case.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger <richard@nod.at>
process_pool_aeb() does several times the be32_to_cpu(new_vh->vol_id)
operation. Create a temporary variable and do it once.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
add_fastmap() is passed a ubi_vid_hdr pointer in argument, but is
referencing the global vidh pointer.
Even if this is correct from a functional point of view (vidh and vid_hdr
point to the same object), it is confusing.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
process_pool_aeb() re-implements the logic found in ubi_find_volume().
Call ubi_find_volume() to avoid this duplication.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
All drivers use the default, so provide an inline version of it. If we
ever need other queue mapping we can add an optional method back,
although supporting will also require major changes to the queue setup
code.
This provides better code generation, and better debugability as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since PEB erasure is asynchornous it can happen that there is
more than one Fastmap on the MTD. This is fine because the attach logic
will pick the Fastmap data structure with the highest sequence number.
On a not so well configured MTD stack spurious ECC errors are common.
Causes can be different, bad hardware, wrong operating modes, etc...
If the most current Fastmap renders bad due to ECC errors UBI might
pick an older Fastmap to attach from.
While this can only happen on an anyway broken setup it will show
completely different sympthoms and makes finding the root cause much
more difficult.
So, be debug friendly and fall back to scanning mode of we're facing
an ECC error while scanning for Fastmap.
Cc: <stable@vger.kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
This helps to detect cases where an user copies an UBI image to
another target with different bad blocks.
Signed-off-by: Richard Weinberger <richard@nod.at>
Introduce a new list to the UBI attach information
object to be able to deal better with old and corrupted
Fastmap eraseblocks.
Also move more Fastmap specific code into fastmap.c.
Signed-off-by: Richard Weinberger <richard@nod.at>
When the volume resize operation shrinks a volume,
LEBs will be unmapped. Since unmapping will not erase these
LEBs immediately we have to wait for that operation to finish.
Otherwise in case of a power cut right after writing the new
volume table the UBI attach process can find more LEBs than the
volume table knows. This will render the UBI image unattachable.
Fix this issue by waiting for erase to complete and write the new
volume table afterward.
Cc: <stable@vger.kernel.org>
Reported-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
We cannot use ubi_* logging functions before the UBI
object is initialized.
Cc: <stable@vger.kernel.org>
Fixes: 3260870331 ("UBI: Extend UBI layer debug/messaging capabilities")
Signed-off-by: Richard Weinberger <richard@nod.at>
There is no need to call get/put on the module
reference in gluebi_get/put_device() callbacks.
Since mtd->owner is the gluebi module itself
mtdcore.c will take care of proper refcounting
in __get/put_mtd_device() before executing the
callbacks.
Signed-off-by: Richard Weinberger <richard@nod.at>
Install the UBI device object before we arm sysfs.
Otherwise udev tries to read sysfs attributes before UBI is ready and
udev rules will not match.
Cc: <stable@vger.kernel.org>
Signed-off-by: Iosif Harutyunov <iharutyunov@sonicwall.com>
[rw: massaged commit message]
Signed-off-by: Richard Weinberger <richard@nod.at>
When reading the vid hdr from the device UBI always reads a whole
page. Instead, read only the data we actually need and speed up
attachment of UBI devices by potentially making use of reading
subpages if the NAND driver supports it.
Since the VID header may be at offset vid_hdr_shift in the page and
we can only read from the beginning of a page we have to add that
offset to the read size.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
recover_peb() was never power cut aware,
if a power cut happened right after writing the VID header
upon next attach UBI would blindly use the new partial written
PEB and all data from the old PEB is lost.
In order to make recover_peb() power cut aware, write the new
VID with a proper crc and copy_flag set such that the UBI attach
process will detect whether the new PEB is completely written
or not.
We cannot directly use ubi_eba_atomic_leb_change() since we'd
have to unlock the LEB which is facing a write error.
Cc: stable@vger.kernel.org
Reported-by: Jörg Pfähler <pfaehler@isse.de>
Reviewed-by: Jörg Pfähler <pfaehler@isse.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Directly accessing inode fields bypasses ->getattr()
and can cause problems when the underlying filesystem
does not have the default ->getattr() implementation.
So instead of obtaining the backing inode via d_backing_inode()
use vfs_getattr() and obtain what we need from the kstat struct.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
This reverts commit 87f15d4add.
vfs_stat() can only be used on user supplied buffers.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
This reverts commit 322ea0bbf3.
vfs_stat() can only be used on user supplied buffers.
UBI's kapi.c is the API to the kernel and therefore vfs_stat()
is inappropriate.
This solves the problem that mounting any UBIFS will immediately
fail with -EINVAL.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
improvements of UBI and UBIFS.
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Merge tag 'upstream-4.7-rc1' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS updates from Richard Weinberger:
"This contains mostly cleanups and minor improvements of UBI and UBIFS"
* tag 'upstream-4.7-rc1' of git://git.infradead.org/linux-ubifs:
ubifs: ubifs_dump_inode: Fix dumping field bulk_read
UBI: Fix static volume checks when Fastmap is used
UBI: Set free_count to zero before walking through erase list
UBI: Silence an unintialized variable warning
UBI: Clean up return in ubi_remove_volume()
UBI: Modify wrong comment in ubi_leb_map function.
UBI: Don't read back all data in ubi_eba_copy_leb()
UBI: Add ro-mode sysfs attribute
Ezequiel reported that he's facing UBI going into read-only
mode after power cut. It turned out that this behavior happens
only when updating a static volume is interrupted and Fastmap is
used.
A possible trace can look like:
ubi0 warning: ubi_io_read_vid_hdr [ubi]: no VID header found at PEB 2323, only 0xFF bytes
ubi0 warning: ubi_eba_read_leb [ubi]: switch to read-only mode
CPU: 0 PID: 833 Comm: ubiupdatevol Not tainted 4.6.0-rc2-ARCH #4
Hardware name: SAMSUNG ELECTRONICS CO., LTD. 300E4C/300E5C/300E7C/NP300E5C-AD8AR, BIOS P04RAP 10/15/2012
0000000000000286 00000000eba949bd ffff8800c45a7b38 ffffffff8140d841
ffff8801964be000 ffff88018eaa4800 ffff8800c45a7bb8 ffffffffa003abf6
ffffffff850e2ac0 8000000000000163 ffff8801850e2ac0 ffff8801850e2ac0
Call Trace:
[<ffffffff8140d841>] dump_stack+0x63/0x82
[<ffffffffa003abf6>] ubi_eba_read_leb+0x486/0x4a0 [ubi]
[<ffffffffa00453b3>] ubi_check_volume+0x83/0xf0 [ubi]
[<ffffffffa0039d97>] ubi_open_volume+0x177/0x350 [ubi]
[<ffffffffa00375d8>] vol_cdev_open+0x58/0xb0 [ubi]
[<ffffffff8124b08e>] chrdev_open+0xae/0x1d0
[<ffffffff81243bcf>] do_dentry_open+0x1ff/0x300
[<ffffffff8124afe0>] ? cdev_put+0x30/0x30
[<ffffffff81244d36>] vfs_open+0x56/0x60
[<ffffffff812545f4>] path_openat+0x4f4/0x1190
[<ffffffff81256621>] do_filp_open+0x91/0x100
[<ffffffff81263547>] ? __alloc_fd+0xc7/0x190
[<ffffffff812450df>] do_sys_open+0x13f/0x210
[<ffffffff812451ce>] SyS_open+0x1e/0x20
[<ffffffff81a99e32>] entry_SYSCALL_64_fastpath+0x1a/0xa4
UBI checks static volumes for data consistency and reads the
whole volume upon first open. If the volume is found erroneous
users of UBI cannot read from it, but another volume update is
possible to fix it. The check is performed by running
ubi_eba_read_leb() on every allocated LEB of the volume.
For static volumes ubi_eba_read_leb() computes the checksum of all
data stored in a LEB. To verify the computed checksum it has to read
the LEB's volume header which stores the original checksum.
If the volume header is not found UBI treats this as fatal internal
error and switches to RO mode. If the UBI device was attached via a
full scan the assumption is correct, the volume header has to be
present as it had to be there while scanning to get known as mapped.
If the attach operation happened via Fastmap the assumption is no
longer correct. When attaching via Fastmap UBI learns the mapping
table from Fastmap's snapshot of the system state and not via a full
scan. It can happen that a LEB got unmapped after a Fastmap was
written to the flash. Then UBI can learn the LEB still as mapped and
accessing it returns only 0xFF bytes. As UBI is not a FTL it is
allowed to have mappings to empty PEBs, it assumes that the layer
above takes care of LEB accounting and referencing.
UBIFS does so using the LEB property tree (LPT).
For static volumes UBI blindly assumes that all LEBs are present and
therefore special actions have to be taken.
The described situation can happen when updating a static volume is
interrupted, either by a user or a power cut.
The volume update code first unmaps all LEBs of a volume and then
writes LEB by LEB. If the sequence of operations is interrupted UBI
detects this either by the absence of LEBs, no volume header present
at scan time, or corrupted payload, detected via checksum.
In the Fastmap case the former method won't trigger as no scan
happened and UBI automatically thinks all LEBs are present.
Only by reading data from a LEB it detects that the volume header is
missing and incorrectly treats this as fatal error.
To deal with the situation ubi_eba_read_leb() from now on checks
whether we attached via Fastmap and handles the absence of a
volume header like a data corruption error.
This way interrupted static volume updates will correctly get detected
also when Fastmap is used.
Cc: <stable@vger.kernel.org>
Reported-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Richard Weinberger <richard@nod.at>
Set free_count to zero before walking through ai->erase list
in wl_init().
Found in U-Boot as U-Boot has no workqueue/threads, it immediately
calls erase_worker(), which increase for each erased block
free_count. Without this patch, free_count gets after
this initialized to zero in wl_init(), so the free_count
variable always has the maybe wrong value 0 in U-Boot.
Signed-off-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
My static checker complains that "val" is uninitialized when kstrtoint()
fails.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
My static checker says that "err" can be uninitialized if
"vol->reserved_pebs" is <= 0. I don't think that can happen but
returning a literal is cleaner anyway.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
