Commit Graph

691898 Commits

Author SHA1 Message Date
Damien Le Moal
615d22a51c block: Fix __blkdev_issue_zeroout loop
The BIO issuing loop in __blkdev_issue_zeroout() is allocating BIOs
with a maximum number of bvec (pages) equal to

min(nr_sects, (sector_t)BIO_MAX_PAGES)

This works since the requested number of bvecs will always be limited
to the absolute maximum number supported (BIO_MAX_PAGES), but this is
ineficient as too many bvec entries may be requested due to the
different units being used in the min() operation (number of sectors vs
number of pages).
To fix this, introduce the helper __blkdev_sectors_to_bio_pages() to
correctly calculate the number of bvecs for zeroout BIOs as the issuing
loop progresses. The calculation is done using consistent units and
makes sure that the number of pages return is at least 1 (for cases
where the number of sectors is less that the number of sectors in
a page).

Also remove a trailing space after the bit shift in the internal loop
min() call.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-06 09:43:20 -06:00
Logan Gunthorpe
854b1dd9c3 ntb_netdev: set the net_device's parent
At present, ntb_netdev devices end up under /sys/devices/virtual/net
completely unconnected to the ntb trees below them. This patch sets the
parent of the net_device (using SET_NETDEV_DEV) to the client_dev
device. This results in a better connected sysfs path for the network
device:

/sys/devices/pci0000:00/0000:00:03.0/0000:03:00.1/0000:03:00.1/ntb_netdev0/net/eth2

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:08 -04:00
Gary R Hook
32e0f5bfa5 ntb: Add error path/handling to Debug FS entry creation
If a failure occurs when creating Debug FS entries, unroll all of
the work that's been done.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:08 -04:00
Gary R Hook
8407dd6c16 ntb: Add more debugfs support for ntb_perf testing options
The ntb_perf tool uses module parameters to control the
characteristics of its test.  Enable the changing of these
options through debugfs, and eliminating the need to unload
and reload the module to make changes and run additional tests.

Add a new module parameter that forces the DMA channel
selection onto the same node as the NTB device (default: true).

 - seg_order: Size of the NTB memory window; power of 2.
 - run_order: Size of the data buffer; power of 2.
 - use_dma:   Use DMA or memcpy? Default: 0.
 - on_node:   Only use DMA channel(s) on the NTB node. Default: true.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:08 -04:00
Gary R Hook
0b93a6dbec ntb: Remove debug-fs variables from the context structure
The Debug FS entries manage themselves; we don't need to hang onto
them in the context structure.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Gary R Hook
e9410ff810 ntb: Add a module option to control affinity of DMA channels
The DMA channel(s)/memory used to transfer data to an NTB device
may not be required to be on the same node as the device. Add a
module parameter that allows any candidate channel (aside from
node assocation) and allocated memory to be used.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
bf2a952d31 NTB: Add IDT 89HPESxNTx PCIe-switches support
IDT 89HPESxNTx device series is PCIe-switches, which support
Non-Transparent bridging between domains connected to the device ports.
Since new NTB API exposes multi-port interface and messaging API, the
IDT NT-functions can be now supported in the kernel. This driver adds
the following functionality:
1) Multi-port NTB API to have information of possible NT-functions
activated in compliance with available device ports.
2) Memory windows of direct and look up table based address translation
with all possible combinations of BARs setup.
3) Traditional doorbell NTB API.
4) One-on-one messaging NTB API.

There are some IDT PCIe-switch setups, which must be done before any of
the NTB peers started. It can be performed either by system BIOS via
IDT SMBus-slave interface or by pre-initialized IDT PCIe-switch EEPROM:
1) NT-functions of corresponding ports must be activated using
SWPARTxCTL and SWPORTxCTL registers.
2) BAR0 must be configured to expose NT-function configuration
registers map.
3) The rest of the BARs must have at least one memory window
configured, otherwise the driver will just return an error.
Temperature sensor of IDT PCIe-switches can be also optionally
activated by BIOS or EEPROM.
(See IDT documentations for details of how the pre-initialization can
be done)

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Logan Gunthorpe
48ea02184a ntb_hw_intel: Style fixes: open code macros that just obfuscate code
As per a comments in [1] by Greg Kroah-Hartman, the ndev_* macros should
be cleaned up. This makes it more clear what's actually going on when
reading the code.

[1] http://www.spinics.net/lists/linux-pci/msg56904.html

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Logan Gunthorpe
0f9bfb979a ntb_hw_amd: Style fixes: open code macros that just obfuscate code
As per a comments in [1] by Greg Kroah-Hartman, the ndev_* macros should
be cleaned up. This makes it more clear what's actually going on when
reading the code.

[1] http://www.spinics.net/lists/linux-pci/msg56904.html

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
3c69f5d673 NTB: Add ntb.h comments
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
85dce3aaae NTB: Add PCIe Gen4 link speed
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
cdcca896ae NTB: Add new Memory Windows API documentation
Since the new API slightly changes the way a typical NTB client driver
works, the documentation file needs to be appropriately updated.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
bc3e49adc2 NTB: Add Messaging NTB API
Some IDT NTB-capable PCIe-switches have message registers to communicate with
peer devices. This patch adds new NTB API callback methods, which can be used
to utilize these registers functionality:
 ntb_msg_count(); - get number of message registers
 ntb_msg_inbits(); - get bitfield of inbound message registers status
 ntb_msg_outbits(); - get bitfield of outbound message registers status
 ntb_msg_read_sts(); - read the inbound and outbound message registers status
 ntb_msg_clear_sts(); - clear status bits of message registers
 ntb_msg_set_mask(); - mask interrupts raised by status bits of message
registers.
 ntb_msg_clear_mask(); - clear interrupts mask bits of message registers
 ntb_msg_read(midx, *pidx); - read message register with specified index,
additionally getting peer port index which data received from
 ntb_msg_write(midx, pidx); - write data to the specified message register
sending it to the passed peer device connected over a pidx port
 ntb_msg_event(); - notify driver context of a new message event

Of course there is hardware which doesn't support Message registers, so
this API is made optional.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
d67288a395 NTB: Alter Scratchpads API to support multi-ports devices
Even though there is no any real NTB hardware, which would have both more
than two ports and Scratchpad registers, it is logically correct to have
Scratchpad API accepting a peer port index as well. Intel/AMD drivers utilize
Primary and Secondary topology to split Scratchpad between connected root
devices. Since port-index API introduced, Intel/AMD NTB hardware drivers can
use device port to determine which Scratchpad registers actually belong to
local and peer devices. The same approach can be used if some potential
hardware in future will be multi-port and have some set of Scratchpads.
Here are the brief of changes in the API:
 ntb_spad_count() - return number of Scratchpads per each port
 ntb_peer_spad_addr(pidx, sidx) - address of Scratchpad register of the
peer device with pidx-index
 ntb_peer_spad_read(pidx, sidx) - read specified Scratchpad register of the
peer with pidx-index
 ntb_peer_spad_write(pidx, sidx) - write data to Scratchpad register of the
peer with pidx-index

Since there is hardware which doesn't support Scratchpad registers, the
corresponding API methods are now made optional.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
443b9a14ec NTB: Alter MW API to support multi-ports devices
Multi-port NTB devices permit to share a memory between all accessible peers.
Memory Windows API is altered to correspondingly initialize and map memory
windows for such devices:
 ntb_mw_count(pidx); - number of inbound memory windows, which can be allocated
for shared buffer with specified peer device.
 ntb_mw_get_align(pidx, widx); - get alignment and size restriction parameters
to properly allocate inbound memory region.
 ntb_peer_mw_count(); - get number of outbound memory windows.
 ntb_peer_mw_get_addr(widx); - get mapping address of an outbound memory window

If hardware supports inbound translation configured on the local ntb port:
 ntb_mw_set_trans(pidx, widx); - set translation address of allocated inbound
memory window so a peer device could access it.
 ntb_mw_clear_trans(pidx, widx); - clear the translation address of an inbound
memory window.

If hardware supports outbound translation configured on the peer ntb port:
 ntb_peer_mw_set_trans(pidx, widx); - set translation address of a memory
window retrieved from a peer device
 ntb_peer_mw_clear_trans(pidx, widx); - clear the translation address of an
outbound memory window

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
4e8c11b7fd NTB: Alter link-state API to support multi-port devices
Multi-port devices permit the NTB connections between multiple domains,
so a local device can have NTB link being up with one peer and being
down with another. NTB link-state API is appropriately altered to return
a bitfield of the link-states between the local device and possible peers.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
1e5301196a NTB: Add indexed ports NTB API
There is some NTB hardware, which can combine more than just two domains
over NTB. For instance, some IDT PCIe-switches can have NTB-functions
activated on more than two-ports. The different domains are distinguished
by ports they are connected to. So the new port-related methods are added to
the NTB API:
 ntb_port_number() - return local port
 ntb_peer_port_count() - return number of peers local port can connect to
 ntb_peer_port_number(pdix) - return port number by it index
 ntb_peer_port_idx(port) - return port index by it number

Current test-drivers aren't changed much. They still support two-ports devices
for the time being while multi-ports hardware drivers aren't added.

By default port-related API is declared for two-ports hardware.
So corresponding hardware drivers won't need to implement it.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Serge Semin
60934b200d NTB: Make link-state API being declared first
Since link operations are usually performed before memory window access
operations, it's logically better to declare link-related API before any
of MW/Doorbell/Scratchpad methods.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:07 -04:00
Allen Hubbe
7c49c9855a NTB: ntb_test: add parameter for doorbell bitmask
If the test attempts to clear doorbell bits that are invalid for the
hardware, then the test will fail.  Provide a parameter to specify the
doorbell bits to clear.  Set default doorbell bits that work for XEON.

Signed-off-by: Allen Hubbe <Allen.Hubbe@dell.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:06 -04:00
Allen Hubbe
c2d42edb52 NTB: ntb_test: modprobe on remote host
Signed-off-by: Allen Hubbe <Allen.Hubbe@dell.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-07-06 11:30:06 -04:00
Thierry Reding
5ec8c48a62 Merge branch 'for-4.13/drivers' into for-next 2017-07-06 17:16:47 +02:00
Thierry Reding
72f2ebbdf4 Merge branch 'for-4.13/dt' into for-next 2017-07-06 17:16:46 +02:00
Thierry Reding
d007a00b56 Merge branch 'for-4.13/core' into for-next 2017-07-06 17:16:45 +02:00
Nick Vaccaro
e47866a177 pwm: cros-ec: Fix transposed param settings
The __cros_ec_pwm_get_duty() routine was transposing the insize and
outsize fields when calling cros_ec_cmd_xfer_status().

The original code worked without error due to size of the two particular
parameter blocks passed to cros_ec_cmd_xfer_status(), so this change is
not fixing an actual runtime problem, just correcting the calling usage.

Signed-off-by: Nick Vaccaro <nvaccaro@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-07-06 17:16:37 +02:00
Jerome Brunet
fd7b2be8cb pwm: meson: Improve PWM calculation precision
When using input clocks with high rates, such as clk81 (166MHz), the
fin_ns = NSEC_PER_SEC / fin_freq can introduce a significant error.

Ex: fin_freq = 166666667, NSEC_PER_SEC = 1000000000
    fin_ns = 5,9999999

which is, of course, rounded down to 5. This introduces an error of ~20%
on the period requested from the PWM.

This patch uses ps instead of ns (and 64 bit integers) to perform the
calculation. This should give a good enough precision.

Fixes: 211ed63075 ("pwm: Add support for Meson PWM Controller")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

squash! pwm: meson: Improve pwm calculation precision
2017-07-06 17:15:43 +02:00
Michael Sartain
99c621d704 tracing: Add saved_tgids file to show cached pid to tgid mappings
Export the cached pid / tgid mappings in debugfs tracing saved_tgids file.
This allows user apps to translate the pids from a trace to their respective
thread group.

Example saved_tgids file with pid / tgid values separated by ' ':

  # cat saved_tgids
  1048 1048
  1047 1047
  7 7
  1049 1047
  1054 1047
  1053 1047

Link: http://lkml.kernel.org/r/20170630004023.064965233@goodmis.org
Link: http://lkml.kernel.org/r/20170706040713.unwkumbta5menygi@mikesart-cos

Reviewed-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Michael Sartain <mikesart@fastmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-06 10:11:53 -04:00
Al Viro
62473a2d6f move file_{start,end}_write() out of do_iter_write()
... and do *not* grab it in vfs_write_iter().

Fixes: "fs: implement vfs_iter_read using do_iter_read"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-07-06 09:15:47 -04:00
David S. Miller
c644bd79c0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains two Netfilter fixes for your net tree,
they are:

1) Fix memleak from netns release path of conntrack protocol trackers,
   patch from Liping Zhang.

2) Uninitialized flags field in ebt_log, that results in unpredictable
   logging format in ebtables, also from Liping.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-06 14:02:22 +01:00
Huy Nguyen
d968f0f2e4 net/mlx5e: Initialize CEE's getpermhwaddr address buffer to 0xff
Latest change in open-lldp code uses bytes 6-11 of perm_addr buffer
as the Ethernet source address for the host TLV packet.
Since our driver does not fill these bytes, they stay at zero and
the open-lldp code ends up sending the TLV packet with zero source
address and the switch drops this packet.

The fix is to initialize these bytes to 0xff. The open-lldp code
considers 0xff:ff:ff:ff:ff:ff as the invalid address and falls back to
use the host's mac address as the Ethernet source address.

Fixes: 3a6a931dfb ("net/mlx5e: Support DCBX CEE API")
Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:20 +03:00
Ilan Tayari
fb000f7817 net/mlx5: Add Makefiles for subdirectories
Currently it is not possible to build just one .o file inside
a subdirectory, because the subdirectories lack a Makefile.

Add a Makefile to the mlx5 subdirectories.

Fixes: e29341fb3a ("net/mlx5: FPGA, Add basic support for Innova")
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:20 +03:00
Ilan Tayari
111a676367 net/mlx5: Build wq.o even if MLX5_CORE_EN is not selected
Both the ethernet and FPGA portions of MLX5 now require the wq functions,
and we get a link error when CONFIG_MLX5_CORE_EN is disabled:

drivers/net/ethernet/mellanox/mlx5/core/fpga/conn.o: In function `mlx5_fpga_conn_create_cq':
conn.c:(.text+0x10b3): undefined reference to `mlx5_cqwq_create'
conn.c:(.text+0x10c6): undefined reference to `mlx5_cqwq_get_size'
conn.c:(.text+0x12bc): undefined reference to `mlx5_cqwq_destroy'

Build wq.o even if MLX5_CORE_EN is not selected.

Fixes: 537a505741 ("net/mlx5: FPGA, Add high-speed connection routines")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:20 +03:00
Ilan Tayari
2a41d15b79 net/mlx5: FPGA, Fix datatype mismatch
Fix warnings when building with -Wall:
drivers/net/ethernet/mellanox/mlx5/core/fpga/ipsec.c:313:36: warning: cast to restricted __be32
drivers/net/ethernet/mellanox/mlx5/core/fpga/ipsec.c:314:37: warning: cast to restricted __be32

Fixes: bebb23e6cb ("net/mlx5: Accel, Add IPSec acceleration interface")
Reported-by: Or Gerlitz <gerlitz.or@gmail.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:20 +03:00
Ilan Tayari
c8af01692e net/mlx5: FPGA, make mlx5_fpga_device_brb static
Fix warning when building with -Wall:
drivers/net/ethernet/mellanox/mlx5/core/fpga/core.c:105:5: warning: symbol 'mlx5_fpga_device_brb' was not declared. Should it be static?

Fixes: c43051d72a ("net/mlx5: FPGA, Add SBU bypass and reset flows")
Reported-by: Or Gerlitz <gerlitz.or@gmail.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:20 +03:00
Ilan Tayari
5dfd87b67c net/mlx5: IPSec, Fix 64-bit division on 32-bit builds
Fix warnings when building 386 kernel:
>> ERROR: "__udivdi3" [drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko] undefined!

Fixes: 2ac9cfe782 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data path")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:19 +03:00
Ilan Tayari
aa07b63384 net/mlx5: Add missing include in lib/gid.c
Fix warnings when building with -Wall:
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:38:6: warning: symbol 'mlx5_init_reserved_gids' was not declared. Should it be static?
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:47:6: warning: symbol 'mlx5_cleanup_reserved_gids' was not declared. Should it be static?
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:55:5: warning: symbol 'mlx5_core_reserve_gids' was not declared. Should it be static?
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:79:6: warning: symbol 'mlx5_core_unreserve_gids' was not declared. Should it be static?
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:92:5: warning: symbol 'mlx5_core_reserved_gid_alloc' was not declared. Should it be static?
drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c:109:6: warning: symbol 'mlx5_core_reserved_gid_free' was not declared. Should it be static?

Fixes: 52ec462eca ("net/mlx5: Add reserved-gids support")
Reported-by: Or Gerlitz <gerlitz.or@gmail.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2017-07-06 15:13:19 +03:00
Jeff Layton
333427a505 btrfs: minimal conversion to errseq_t writeback error reporting on fsync
Just check and advance the errseq_t in the file before returning, and
use an errseq_t based check for writeback errors.

Other internal callers of filemap_* functions are left as-is.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:31 -04:00
Jeff Layton
1b180274f5 xfs: minimal conversion to errseq_t writeback error reporting
Just check and advance the data errseq_t in struct file before
before returning from fsync on normal files. Internal filemap_*
callers are left as-is.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:30 -04:00
Jeff Layton
6acec592c6 ext4: use errseq_t based error handling for reporting data writeback errors
Add a call to filemap_report_wb_err at the end of ext4_sync_file. This
will ensure that we check and advance the errseq_t in the file, which
allows us to track and report errors on all open fds when they occur.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:30 -04:00
Jeff Layton
383aa543c2 fs: convert __generic_file_fsync to use errseq_t based reporting
Many simple, block-based filesystems use generic_file_fsync as their
fsync operation. Some others (ext* and fat) also call this function
to handle syncing out data.

Switch this code over to use errseq_t based error reporting so that
all of these filesystems get reliable error reporting via fsync,
fdatasync and msync.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:29 -04:00
Jeff Layton
372cf243ea block: convert to errseq_t based writeback error tracking
This is a very minimal conversion to errseq_t based error tracking
for raw block device access. Just have it use the standard
file_write_and_wait_range call.

Note that there are internal callers that call sync_blockdev
and the like that are not affected by this. They'll continue
to use the AS_EIO/AS_ENOSPC flags for error reporting like
they always have for now.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:28 -04:00
Jeff Layton
819ec6b91d dax: set errors in mapping when writeback fails
Jan Kara's description for this patch is much better than mine, so I'm
quoting it verbatim here:

DAX currently doesn't set errors in the mapping when cache flushing
fails in dax_writeback_mapping_range(). Since this function can get
called only from fsync(2) or sync(2), this is actually as good as it can
currently get since we correctly propagate the error up from
dax_writeback_mapping_range() to filemap_fdatawrite()

However, in the future better writeback error handling will enable us to
properly report these errors on fsync(2) even if there are multiple file
descriptors open against the file or if sync(2) gets called before
fsync(2). So convert DAX to using standard error reporting through the
mapping.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-and-tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2017-07-06 07:02:27 -04:00
Jeff Layton
acbf3c3452 Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
Let's try to make this extra clear for fs authors.

Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:27 -04:00
Jeff Layton
8ed1e46aaf mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
When a writeback error occurs, we want later callers to be able to pick
up that fact when they go to wait on that writeback to complete.
Traditionally, we've used AS_EIO/AS_ENOSPC flags to track that, but
that's problematic since only one "checker" will be informed when an
error occurs.

In later patches, we're going to want to convert many of these callers
to check for errors since a well-defined point in time. For now, ensure
that we can handle both sorts of checks by both setting errors in both
places when there is a writeback failure.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:26 -04:00
Jeff Layton
5660e13d2f fs: new infrastructure for writeback error handling and reporting
Most filesystems currently use mapping_set_error and
filemap_check_errors for setting and reporting/clearing writeback errors
at the mapping level. filemap_check_errors is indirectly called from
most of the filemap_fdatawait_* functions and from
filemap_write_and_wait*. These functions are called from all sorts of
contexts to wait on writeback to finish -- e.g. mostly in fsync, but
also in truncate calls, getattr, etc.

The non-fsync callers are problematic. We should be reporting writeback
errors during fsync, but many places spread over the tree clear out
errors before they can be properly reported, or report errors at
nonsensical times.

If I get -EIO on a stat() call, there is no reason for me to assume that
it is because some previous writeback failed. The fact that it also
clears out the error such that a subsequent fsync returns 0 is a bug,
and a nasty one since that's potentially silent data corruption.

This patch adds a small bit of new infrastructure for setting and
reporting errors during address_space writeback. While the above was my
original impetus for adding this, I think it's also the case that
current fsync semantics are just problematic for userland. Most
applications that call fsync do so to ensure that the data they wrote
has hit the backing store.

In the case where there are multiple writers to the file at the same
time, this is really hard to determine. The first one to call fsync will
see any stored error, and the rest get back 0. The processes with open
fds may not be associated with one another in any way. They could even
be in different containers, so ensuring coordination between all fsync
callers is not really an option.

One way to remedy this would be to track what file descriptor was used
to dirty the file, but that's rather cumbersome and would likely be
slow. However, there is a simpler way to improve the semantics here
without incurring too much overhead.

This set adds an errseq_t to struct address_space, and a corresponding
one is added to struct file. Writeback errors are recorded in the
mapping's errseq_t, and the one in struct file is used as the "since"
value.

This changes the semantics of the Linux fsync implementation such that
applications can now use it to determine whether there were any
writeback errors since fsync(fd) was last called (or since the file was
opened in the case of fsync having never been called).

Note that those writeback errors may have occurred when writing data
that was dirtied via an entirely different fd, but that's the case now
with the current mapping_set_error/filemap_check_error infrastructure.
This will at least prevent you from getting a false report of success.

The new behavior is still consistent with the POSIX spec, and is more
reliable for application developers. This patch just adds some basic
infrastructure for doing this, and ensures that the f_wb_err "cursor"
is properly set when a file is opened. Later patches will change the
existing code to use this new infrastructure for reporting errors at
fsync time.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-06 07:02:25 -04:00
Jeff Layton
84cbadadc6 lib: add errseq_t type and infrastructure for handling it
An errseq_t is a way of recording errors in one place, and allowing any
number of "subscribers" to tell whether an error has been set again
since a previous time.

It's implemented as an unsigned 32-bit value that is managed with atomic
operations. The low order bits are designated to hold an error code
(max size of MAX_ERRNO). The upper bits are used as a counter.

The API works with consumers sampling an errseq_t value at a particular
point in time. Later, that value can be used to tell whether new errors
have been set since that time.

Note that there is a 1 in 512k risk of collisions here if new errors
are being recorded frequently, since we have so few bits to use as a
counter. To mitigate this, one bit is used as a flag to tell whether the
value has been sampled since a new value was recorded. That allows
us to avoid bumping the counter if no one has sampled it since it
was last bumped.

Later patches will build on this infrastructure to change how writeback
errors are tracked in the kernel.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-06 07:02:24 -04:00
Jeff Layton
5e8fcc1a0f mm: don't TestClearPageError in __filemap_fdatawait_range
The -EIO returned here can end up overriding whatever error is marked in
the address space, and be returned at fsync time, even when there is a
more appropriate error stored in the mapping.

Read errors are also sometimes tracked on a per-page level using
PG_error. Suppose we have a read error on a page, and then that page is
subsequently dirtied by overwriting the whole page. Writeback doesn't
clear PG_error, so we can then end up successfully writing back that
page and still return -EIO on fsync.

Worse yet, PG_error is cleared during a sync() syscall, but the -EIO
return from that is silently discarded. Any subsystem that is relying on
PG_error to report errors during fsync can easily lose writeback errors
due to this. All you need is a stray sync() call to wait for writeback
to complete and you've lost the error.

Since the handling of the PG_error flag is somewhat inconsistent across
subsystems, let's just rely on marking the address space when there are
writeback errors. Change the TestClearPageError call to ClearPageError,
and make __filemap_fdatawait_range a void return function.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:24 -04:00
Jeff Layton
cbeaf9510a mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
filemap_write_and_wait{_range} will return an error if writeback
initiation fails, but won't clear errors in the address_space. This is
particularly problematic on DAX, as filemap_fdatawrite* is
effectively synchronous there. Ensure that we clear the AS_EIO/AS_ENOSPC
flags when filemap_fdatawrite* returns an error.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:23 -04:00
Jeff Layton
76341cabbd jbd2: don't clear and reset errors after waiting on writeback
Resetting this flag is almost certainly racy, and will be problematic
with some coming changes.

Make filemap_fdatawait_keep_errors return int, but not clear the flag(s).
Have jbd2 call it instead of filemap_fdatawait and don't attempt to
re-set the error flag if it fails.

Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:22 -04:00
Jeff Layton
87354e5de0 buffer: set errors in mapping at the time that the error occurs
I noticed on xfs that I could still sometimes get back an error on fsync
on a fd that was opened after the error condition had been cleared.

The problem is that the buffer code sets the write_io_error flag and
then later checks that flag to set the error in the mapping. That flag
perisists for quite a while however. If the file is later opened with
O_TRUNC, the buffers will then be invalidated and the mapping's error
set such that a subsequent fsync will return error. I think this is
incorrect, as there was no writeback between the open and fsync.

Add a new mark_buffer_write_io_error operation that sets the flag and
the error in the mapping at the same time. Replace all calls to
set_buffer_write_io_error with mark_buffer_write_io_error, and remove
the places that check this flag in order to set the error in the
mapping.

This sets the error in the mapping earlier, at the time that it's first
detected.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2017-07-06 07:02:21 -04:00
Jeff Layton
dac257f741 fs: check for writeback errors after syncing out buffers in generic_file_fsync
ext2 currently does a test+clear of the AS_EIO flag, which is
is problematic for some coming changes.

What we really need to do instead is call filemap_check_errors
in __generic_file_fsync after syncing out the buffers. That
will be sufficient for this case, and help other callers detect
these errors properly as well.

With that, we don't need to twiddle it in ext2.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
2017-07-06 07:02:21 -04:00