The new trend in linux is not to store headers which define
on-media format in the include/ directory, but instead, store
them locally. This is because these headers "do not define any
kernel<->userspace interface".
Do so for UBI as well.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
In C, signed 1-bit bitfields can only take the values 0 and -1, only 0 and 1
are ever assigned in current code. Make them unsigned bitfields.
Fixes the (repeated) sparse errors:
drivers/mtd/ubi/ubi.h:220:15: error: dubious one-bit signed bitfield
drivers/mtd/ubi/ubi.h:221:17: error: dubious one-bit signed bitfield
drivers/mtd/ubi/ubi.h:222:18: error: dubious one-bit signed bitfield
drivers/mtd/ubi/ubi.h:223:16: error: dubious one-bit signed bitfield
drivers/mtd/ubi/ubi.h:224:20: error: dubious one-bit signed bitfield
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Instead of passing vol_id to all functions and then find
struct ubi_volume, pass struct ubi_volume pointer.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The problem: NAND flashes have different amount of initial bad physical
eraseblocks (marked as bad by the manufacturer). For example, for 256MiB
Samsung OneNAND flash there might be from 0 to 40 bad initial eraseblocks,
which is about 2%. When UBI is used as the base system, one needs to know
the exact amount of good physical eraseblocks, because this number is
needed to create the UBI image which is put to the devices during
production. But this number is not know, which forces us to use the
minimum number of good physical eraseblocks. And UBI additionally
reserves some percentage of physical eraseblocks for bad block handling
(default is 1%), so we have 1-3% of PEBs reserved at the end, depending
on the amount of initial bad PEBs. But it is desired to always have
1% (or more, depending on the configuration).
Solution: this patch adds an "auto-resize" flag to the volume table.
The volume which has the "auto-resize" flag will automatically be re-sized
(enlarged) on the first UBI initialization. UBI clears the flag when
the volume is re-sized. Only one volume may have the "auto-resize" flag.
So, the production UBI image may have one volume with "auto-resize"
flag set, and its size is automatically adjusted on the first boot
of the device.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This slab cache is not really needed since the number of objects
is low and the constructor does not make much sense because we
allocate oblects when doint I/O, which is way slower then allocation.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Introduce a separate mutex which serializes volumes checking,
because we cammot really use volumes_mutex - it cases reverse
locking problems with mtd_tbl_mutex when gluebi is used -
thanks to lockdep.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Prepare the attach and detach functions to by used outside of
module initialization:
* detach function checks reference count before detaching
* it kills the background thread as well
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This is one more step on the way to "removable" UBI devices. It
adds reference counting for UBI devices. Every time a volume on
this device is opened - the device's refcount is increased. It
is also increased if someone is reading any sysfs file of this
UBI device or of one of its volumes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch is a preparation to make UBI devices dynamic. It
adds an UBI control device which has dynamically allocated
major number and registers itself as "ubi_ctrl". It does not
do anything so far. The idea is that this device will allow
to attach/detach MTD devices from userspace.
This is symilar to what the Linux device mapper has.
The next things to do are:
* Fix UBI, because it now assumes UBI devices cannot go away
* Implement control device ioctls which will attach/detach MTD
devices
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The flush function should finish all the pending jobs. But if
somebody else is doing a work, this function should wait and let
it finish.
This patche uses rw semaphore for synchronization purpose - it
just looks quite convinient.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When the WL worker is moving an LEB, the volume might go away
occasionally. UBI does not handle these situations correctly.
This patch introduces a new mutex which serializes wear-levelling
worker and the the 'ubi_wl_put_peb()' function. Now, if one puts
an LEB, and its PEB is being moved, it will wait on the mutex.
And because we unmap all LEBs when removing volumes, this will make
the volume remove function to wait while the LEB movement
finishes.
Below is an example of an oops which should be fixed by this patch:
Pid: 9167, comm: io_paral Not tainted (2.6.24-rc5-ubi-2.6.git #2)
EIP: 0060:[<f884a379>] EFLAGS: 00010246 CPU: 0
EIP is at prot_tree_del+0x2a/0x63 [ubi]
EAX: f39a90e0 EBX: 00000000 ECX: 00000000 EDX: 00000134
ESI: f39a90e0 EDI: f39a90e0 EBP: f2d55ddc ESP: f2d55dd4
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process io_paral (pid: 9167, ti=f2d54000 task=f72a8030 task.ti=f2d54000)
Stack: f39a95f8 ef6aae50 f2d55e08 f884a511 f88538e1 f884ecea 00000134 00000000
f39a9604 f39a95f0 efea8280 00000000 f39a90e0 f2d55e40 f8847261 f8850c3c
f884eaad 00000001 000000b9 00000134 00000172 000000b9 00000134 00000001
Call Trace:
[<c0105227>] show_trace_log_lvl+0x1a/0x30
[<c01052e2>] show_stack_log_lvl+0xa5/0xca
[<c01053d6>] show_registers+0xcf/0x21b
[<c0105648>] die+0x126/0x224
[<c0119a62>] do_page_fault+0x27f/0x60d
[<c037dd62>] error_code+0x72/0x78
[<f884a511>] ubi_wl_put_peb+0xf0/0x191 [ubi]
[<f8847261>] ubi_eba_unmap_leb+0xaf/0xcc [ubi]
[<f8843c21>] ubi_remove_volume+0x102/0x1e8 [ubi]
[<f8846077>] ubi_cdev_ioctl+0x22a/0x383 [ubi]
[<c017d768>] do_ioctl+0x68/0x71
[<c017d7c6>] vfs_ioctl+0x55/0x271
[<c017da15>] sys_ioctl+0x33/0x52
[<c0104152>] sysenter_past_esp+0x5f/0xa5
=======================
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Add ref_count field to UBI volumes and remove weired "vol->removed"
field. This way things are better understandable and we do not have
to do whold show_attr operation under spinlock.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Pass volume description object to the EBA function which makes
more sense, and EBA function do not have to find the volume
description object by volume ID.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Similarly to ltree_entry_slab, it makes more sense to create
and destroy ubi_wl_entry slab on module initialization/exit.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Since the ltree_entry slab cache is a global entity, which is
used by all UBI devices, it is more logical to create it on
module initialization time and destro on module exit time.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When the UBI device is nearly full, i.e. all LEBs are mapped, we have
only one spare LEB left - the one we reserved for WL purposes. Well,
I do not count the LEBs which were reserved for bad PEB handling -
suppose NOR flash for simplicity. If an "atomic LEB change operation"
is run, and the WL unit is moving a LEB, we have no spare LEBs to
finish the operation and fail, which is not good. Moreover, if there
are 2 or more simultanious "atomic LEB change" requests, only one of
them has chances to succeed, the other will fail with -ENOSPC. Not
good either.
This patch does 2 things:
1. Reserves one PEB for the "atomic LEB change" operation.
2. Serealize the operations so that only on of them may run
at a time (by means of a mutex).
Pointed-to-by: Brijesh Singh <brijesh.s.singh@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
