Commit Graph

28 Commits

Author SHA1 Message Date
Matias Bjørling bf64318564 lightnvm: allow to force mm initialization
System block allows the device to initialize with its configured media
manager. The system blocks is written to disk, and read again when media
manager is determined. For this to work, the backend must store the
data. Device drivers, such as null_blk, does not have any backend
storage. This patch allows the media manager to be initialized without a
storage backend.

It also fix incorrect configuration of capabilities in null_blk, as it
does not support get/set bad block interface.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04 09:19:45 -07:00
Jens Axboe a7fd9a4f3e lightnvm: ensure that nvm_dev_ops can be used without CONFIG_NVM
null_blk defines an empty version of this ops structure if CONFIG_NVM
isn't set, but it doesn't know the type. Move those bits out of the
protection of CONFIG_NVM in the main lightnvm include.

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-13 13:04:11 -07:00
Matias Bjørling 8b4970c41f lightnvm: introduce factory reset
Now that a device can be managed using the system blocks, a method to
reset the device is necessary as well. This patch introduces logic to
reset the device easily to factory state and exposes it through an
ioctl.

The ioctl takes the following flags:

  NVM_FACTORY_ERASE_ONLY_USER
      By default all blocks, except host-reserved blocks are erased upon
      factory reset. Instead of this, only erase host-reserved blocks.
  NVM_FACTORY_RESET_HOST_BLKS
      Mark host-reserved blocks to be erased and set their type to free.
  NVM_FACTORY_RESET_GRWN_BBLKS
      Mark "grown bad blocks" to be erased and set their type to free.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:18 -07:00
Matias Bjørling b769207678 lightnvm: use system block for mm initialization
Use system block information to register the appropriate media manager.
This enables the LightNVM subsystem to instantiate a media manager
selected by the user, instead of relying on automatic detection by each
media manager loaded in the kernel.

A device must now be initialized before it can proceed to initialize its
media manager. Upon initialization, the configured media manager is
automatically initialized as well.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:18 -07:00
Matias Bjørling e3eb3799f7 lightnvm: core on-disk initialization
An Open-Channel SSD shall be initialized before use. To initialize, we
define an on-disk format, that keeps a small set of metadata to bring up
the media manager on top of the device.

The initial step is introduced to allow a user to format the disks for a
given media manager. During format, a system block is stored on one to
three separate luns on the device. Each lun has the system block
duplicated. During initialization, the system block can be retrieved and
the appropriate media manager can initialized.

The on-disk format currently covers (struct nvm_system_block):

 - Magic value "NVMS".
 - Monotonic increasing sequence number.
 - The physical block erase count.
 - Version of the system block format.
 - Media manager type.
 - Media manager superblock physical address.

The interface provides three functions to manage the system block:

 int nvm_init_sysblock(struct nvm_dev *, struct nvm_sb_info *)
 int nvm_get_sysblock(struct nvm *dev, struct nvm_sb_info *)
 int nvm_update_sysblock(struct nvm *dev, struct nvm_sb_info *)

Each implement a part of the logic to manage the system block. The
initialization creates the first system blocks and mark them on the
device. Get retrieves the latest system block by scanning all pages in
the associated system blocks. The update sysblock writes new metadata
and allocates new block if necessary.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:18 -07:00
Matias Bjørling ca5927e7ab lightnvm: introduce mlc lower page table mappings
NAND MLC memories have both lower and upper pages. When programming,
both of these must be written, before data can be read. However,
these lower and upper pages might not placed at even and odd flash
pages, but can be skipped. Therefore each flash memory has its lower
pages defined, which can then be used when programming and to know when
padding are necessary.

This patch implements the lower page definition in the specification,
and exposes it through a simple lookup table at dev->lptbl.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling f9a9995072 lightnvm: add mccap support
Some flash media has extended capabilities, such as programming SLC
pages on MLC/TLC flash, erase/program suspend, scramble and encryption.
MCCAP is introduced to detect support for these capabilities in the
command set.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Javier González ff0e498bfa lightnvm: manage open and closed blocks separately
LightNVM targets need to know the state of the flash block when doing
flash optimizations. An example is implementing a write buffer to
respect the flash page size. Currently, block state is not accounted
for; the media manager only differentiates among free, bad and in-use
blocks.

This patch adds the logic in the generic media manager to enable
targets manage blocks into open and close separately, and it implements
such management in rrpc. It also adds a set of flags to describe the
state of the block (open, closed, free, bad).

In order to avoid taking two locks (nvm_lun and rrpc_lun) consecutively,
we introduce lockless get_/put_block primitives so that the open and
close list locks and future common logic is handled within the nvm_lun
lock.

Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling b5d4acd4cb lightnvm: fix missing grown bad block type
The get/set bad block interface defines good block, factory bad block,
grown bad block, device reserved block, and host reserved block.
Unfortunately the grown bad block was missing, leaving the offsets wrong
for device and host side reserved blocks.

This patch adds the missing type and corrects the offsets.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling 09719b62fd lightnvm: introduce nvm_submit_ppa
Internal logic for both core and media managers, does not have a
backing bio for issuing I/Os. Introduce nvm_submit_ppa to allow raw
I/Os to be submitted to the underlying device driver.

The function request the device, ppa, data buffer and its length and
will submit the I/O synchronously to the device. The return value may
therefore be used to detect any errors regarding the issued I/O.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling 72d256ecc5 lightnvm: move rq->error to nvm_rq->error
Instead of passing request error into the LightNVM modules, incorporate
it into the nvm_rq.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling 81e681d3f7 lightnvm: support multiple ppas in nvm_erase_ppa
Sometimes a user want to erase multiple PPAs at the same time. Extend
nvm_erase_ppa to take multiple ppas and number of ppas to be erased.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:17 -07:00
Matias Bjørling 91276162de lightnvm: refactor end_io functions for sync
To implement sync I/O support within the LightNVM core, the end_io
functions are refactored to take an end_io function pointer instead of
testing for initialized media manager, followed by calling its end_io
function.

Sync I/O can then be implemented using a callback that signal I/O
completion. This is similar to the logic found in blk_to_execute_io().
By implementing it this way, the underlying device I/Os submission logic
is abstracted away from core, targets, and media managers.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:16 -07:00
Matias Bjørling abd805ec9f lightnvm: refactor rqd ppa list into set/free
A device may be driven in single, double or quad plane mode. In that
case, the rqd must have either one, two, or four PPAs set for a single
PPA sent to the device. Refactor this logic into their own
functions to be shared by program/erase/read in the core.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:16 -07:00
Matias Bjørling 069368e918 lightnvm: move ppa erase logic to core
A device may function in single, dual or quad plane mode. The gennvm
media manager manages this with explicit helpers. They convert a single
ppa to 1, 2 or 4 separate ppas in a ppa list. To aid implementation of
recovery and system blocks, this functionality can be moved directly
into the core.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 08:21:16 -07:00
Matias Bjørling 16f26c3aa9 lightnvm: replace req queue with nvmdev for lld
In the case where a request queue is passed to the low lever lightnvm
device drive integration, the device driver might pass its admin
commands through another queue. Instead pass nvm_dev, and let the
low level drive the appropriate queue.

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07 09:14:19 -07:00
Matias Bjørling 57b4bd06ff lightnvm: comments on constants
It is not obvious what NVM_IO_* and NVM_BLK_T_* are used for. Make sure
to comment them appropriately as the other constants.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07 09:14:19 -07:00
Matias Bjørling 08236c6bb2 lightnvm: unconverted ppa returned in get_bb_tbl
The get_bb_tbl function takes ppa as a generic address, which is
converted to the ppa device address within the device driver. When
the update_bbtbl callback is called from get_bb_tbl, the device
specific ppa is used, instead of the generic ppa.

Make sure to pass the generic ppa.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29 14:34:58 -07:00
Javier Gonzalez 2fde0e482d lightnvm: add free and bad lun info to show luns
Add free block, used block, and bad block information to the show debug
interface. This information is used to debug how targets track blocks.

Also, change debug function name to make it more generic.

Signed-off-by: Javier Gonzalez <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-20 08:33:21 -07:00
Javier Gonzalez 0b59733b95 lightnvm: keep track of block counts
Maintain number of in use blocks, free blocks, and bad blocks in a per
lun basis. This allows the upper layers to get information about the
state of each lun.

Also, account for blocks reserved to the device on the free block count.
nr_free_blocks matches now the actual number of blocks on the free list
when the device is booted.

Signed-off-by: Javier Gonzalez <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-20 08:33:20 -07:00
Matias Bjørling 7386af270c lightnvm: remove linear and device addr modes
The linear and device specific address modes can be replaced with a
simple offset and bit length conversion that is generic across all
devices.

This both simplifies the specification and removes the special case for
qemu nvme, that previously relied on the linear address mapping.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16 15:20:34 -07:00
Matias Bjørling 73387e7bed lightnvm: remove unused attrs in nvm_id structs
The nvm_id, nvm_id_group and nvm_addr_format data structures contain
reserved attributes. They are unused by media managers and targets.
Remove them.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16 15:20:28 -07:00
Matias Bjørling 12be5edf68 lightnvm: expose mccap in identify command
The mccap field is required for I/O command option support. It defines the
following flash access modes:

 * SLC mode
 * Erase/Program Suspension
 * Scramble On/Off
 * Encryption

It is slotted in between mpos and cpar, changing the offset for
cpar as well.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16 15:20:27 -07:00
Matias Bjørling 1145046983 lightnvm: update bad block table format
The specification was changed to reflect a multi-value bad block table.
Instead of bit-based bad block table, the bad block table now allows
eight bad block categories. Currently four are defined:

 * Factory bad blocks
 * Grown bad blocks
 * Device-side reserved blocks
 * Host-side reserved blocks

The factory and grown bad blocks are the regular bad blocks. The
reserved blocks are either for internal use or external use. In
particular, the device-side reserved blocks allows the host to
bootstrap from a limited number of flash blocks. Reducing the flash
blocks to scan upon super block initialization.

Support for both get bad block table and set bad block table is added.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16 15:20:25 -07:00
Matias Bjørling aedf17f451 lightnvm: change max_phys_sect to uint
The max_phys_sect variable is defined as a char. We do a boundary check
to maximally allow 256 physical page descriptors per command. As we are
not indexing from zero. This expression is always false. Bump the
max_phys_sect to an unsigned int to support the range check.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16 15:20:23 -07:00
Jens Axboe dece16353e block: change ->make_request_fn() and users to return a queue cookie
No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.

Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
2015-11-07 10:40:46 -07:00
Matias Bjørling b7ceb7d500 lightnvm: refactor phys addrs type to u64
For cases where CONFIG_LBDAF is not set. The struct ppa_addr exceeds its
type on 32 bit architectures. ppa_addr requires a 64bit integer to hold
the generic ppa format. We therefore refactor it to u64 and
replaces the sector_t usages with u64 for physical addresses.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-03 09:53:24 -07:00
Matias Bjørling cd9e9808d1 lightnvm: Support for Open-Channel SSDs
Open-channel SSDs are devices that share responsibilities with the host
in order to implement and maintain features that typical SSDs keep
strictly in firmware. These include (i) the Flash Translation Layer
(FTL), (ii) bad block management, and (iii) hardware units such as the
flash controller, the interface controller, and large amounts of flash
chips. In this way, Open-channels SSDs exposes direct access to their
physical flash storage, while keeping a subset of the internal features
of SSDs.

LightNVM is a specification that gives support to Open-channel SSDs
LightNVM allows the host to manage data placement, garbage collection,
and parallelism. Device specific responsibilities such as bad block
management, FTL extensions to support atomic IOs, or metadata
persistence are still handled by the device.

The implementation of LightNVM consists of two parts: core and
(multiple) targets. The core implements functionality shared across
targets. This is initialization, teardown and statistics. The targets
implement the interface that exposes physical flash to user-space
applications. Examples of such targets include key-value store,
object-store, as well as traditional block devices, which can be
application-specific.

Contributions in this patch from:

  Javier Gonzalez <jg@lightnvm.io>
  Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
  Jesper Madsen <jmad@itu.dk>

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-10-29 16:21:42 +09:00