A mirror of the official Linux kernel repository just in case
Go to file
Nikolay Borisov 4eaaec24c0 btrfs: Don't discard unwritten extents
All callers of btrfs_free_reserved_extent (respectively
__btrfs_free_reserved_extent with in set to 0) pass in extents which
have only been reserved but not yet written to. Namely,

* in cow_file_range that function is called only if create_io_em fails
  or btrfs_add_ordered_extent fail, both of which happen _before_ any IO
  is submitted to the newly reserved range

* in submit_compressed_extents the code flow is similar -
  out_free_reserve can be called only before
  btrfs_submit_compressed_write which is where any writes to the range
  could occur

* btrfs_new_extent_direct also calls btrfs_free_reserved_extent only
  if extent_map fails, before any IO is issued

* __btrfs_prealloc_file_range also calls btrfs_free_reserved_extent
  in case insertion of the metadata fails

* btrfs_alloc_tree_block again can only be called in case in-memory
  operations fail, before any IO is submitted

* btrfs_finish_ordered_io - this is the only caller where discarding
  the extent could have a material effect, since it can be called for
  an extent which was partially written.

With this change the submission of discards is optimised since discards
are now not being created for extents which are known to not have been
touched on disk.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-20 16:40:50 +01:00
arch RISC-V updates for v5.5-rc7 2020-01-19 12:10:28 -08:00
block block: fix an integer overflow in logical block size 2020-01-15 21:43:09 -07:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto tpmdd fixes for Linux v5.5-rc3 2019-12-18 17:17:36 -08:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
drivers Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
fs btrfs: Don't discard unwritten extents 2020-01-20 16:40:50 +01:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
init mm, debug_pagealloc: don't rely on static keys too early 2020-01-13 18:19:02 -08:00
ipc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
lib lib/vdso: Make __cvdso_clock_getres() static 2020-01-10 19:29:01 +01:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is valid 2020-01-13 18:19:02 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
samples samples/seccomp: Zero out members based on seccomp_notif_sizes 2020-01-02 13:03:39 -08:00
scripts Kbuild fixes for v5.5 (2nd) 2020-01-03 11:21:25 -08:00
security + Bug fixes 2020-01-04 19:28:30 -08:00
sound sound fixes for 5.5-rc7 2020-01-17 08:38:35 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
usr gen_initramfs_list.sh: fix 'bad variable name' error 2020-01-04 00:00:48 +09:00
virt PPC KVM fix for 5.5 2019-12-22 13:18:15 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap MAINTAINERS: update my email address 2020-01-11 14:33:39 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-19 12:03:53 -08:00
Makefile Linux 5.5-rc7 2020-01-19 16:02:49 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.