Jens Axboe
edafccee56
io_uring: add support for pre-mapped user IO buffers ...
If we have fixed user buffers, we can map them into the kernel when we
setup the io_uring. That avoids the need to do get_user_pages() for
each and every IO.
To utilize this feature, the application must call io_uring_register()
after having setup an io_uring instance, passing in
IORING_REGISTER_BUFFERS as the opcode. The argument must be a pointer to
an iovec array, and the nr_args should contain how many iovecs the
application wishes to map.
If successful, these buffers are now mapped into the kernel, eligible
for IO. To use these fixed buffers, the application must use the
IORING_OP_READ_FIXED and IORING_OP_WRITE_FIXED opcodes, and then
set sqe->index to the desired buffer index. sqe->addr..sqe->addr+seq->len
must point to somewhere inside the indexed buffer.
The application may register buffers throughout the lifetime of the
io_uring instance. It can call io_uring_register() with
IORING_UNREGISTER_BUFFERS as the opcode to unregister the current set of
buffers, and then register a new set. The application need not
unregister buffers explicitly before shutting down the io_uring
instance.
It's perfectly valid to setup a larger buffer, and then sometimes only
use parts of it for an IO. As long as the range is within the originally
mapped region, it will work just fine.
For now, buffers must not be file backed. If file backed buffers are
passed in, the registration will fail with -1/EOPNOTSUPP. This
restriction may be relaxed in the future.
RLIMIT_MEMLOCK is used to check how much memory we can pin. A somewhat
arbitrary 1G per buffer size is also imposed.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-28 08:24:23 -07:00
afs: Fix race in async call refcounting
2019-01-17 15:17:28 +00:00
autofs: fix error return in autofs_fill_super()
2019-02-01 15:46:24 -08:00
bfs: extra sanity checking and static inode bitmap
2019-01-04 13:13:47 -08:00
Linux 5.0-rc6
2019-02-15 08:43:59 -07:00
fscache, cachefiles: remove redundant variable 'cache'
2018-11-30 16:00:58 +00:00
ceph: quota: cleanup license mess
2019-01-21 14:53:23 +01:00
cifs: update internal module version number
2019-01-31 07:05:06 -06:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
debugfs: debugfs_lookup() should return NULL if not found
2019-01-30 12:39:49 +01:00
dlm: fix invalid cluster name warning
2018-12-03 15:30:24 -06:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
exportfs: do not read dentry after free
2018-11-23 09:08:17 -05:00
\n
2018-12-27 17:00:35 -08:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
Merge branch 'akpm' (patches from Andrew)
2019-01-05 09:16:18 -08:00
fscache: fix race between enablement and dropping of object
2018-11-30 15:57:31 +00:00
fuse: decrement NR_WRITEBACK_TEMP on the right page
2019-01-16 10:27:59 +01:00
iomap: wire up the iopoll method
2019-02-24 08:20:17 -07:00
hfs: do not free node before using
2018-11-30 14:56:14 -08:00
hfsplus: return file attributes on statx
2019-01-04 13:13:47 -08:00
hugetlbfs: revert "Use i_mmap_rwsem to fix page fault/truncate race"
2019-01-08 17:15:11 -08:00
jbd2: clean up indentation issue, replace spaces with tab
2018-12-04 00:20:10 -05:00
jffs2: Fix use of uninitialized delayed_work, lockdep breakage
2018-12-02 09:20:34 +01:00
kernfs: Improve kernfs_notify() poll notification latency
2018-11-27 11:59:33 +01:00
NFS client updates for Linux 4.21
2019-01-02 16:35:23 -08:00
NFS: Fix up return value on fatal errors in nfs_page_async_flush()
2019-01-29 16:33:24 -05:00
nfsd: Fix error return values for nfsd4_clone_file_range()
2019-02-06 15:32:05 -05:00
nilfs2: Use xa_erase_irq
2018-11-05 14:57:05 -05:00
inotify: Fix fd refcount leak in inotify_add_watch().
2019-01-02 18:28:37 +01:00
mm: convert totalram_pages and totalhigh_pages variables to atomic
2018-12-28 12:11:47 -08:00
Merge branch 'akpm' (patches from Andrew)
2019-01-05 09:16:18 -08:00
fs/openpromfs: Use of_node_name_eq for node name comparisons
2018-11-18 13:35:19 -08:00
fs: don't open code lru_to_page()
2019-01-04 13:13:48 -08:00
Revert "ovl: relax permission checking on underlying layers"
2018-12-04 11:31:30 +01:00
proc: fix /proc/net/* after setns(2)
2019-02-01 15:46:22 -08:00
pstore/ram: Avoid allocation and leak of platform data
2019-01-20 14:44:52 -08:00
quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
2018-12-18 18:29:15 +01:00
sysfs: convert BUG_ON to WARN_ON
2019-01-07 08:53:32 +01:00
sysv: return 'err' instead of 0 in __sysv_write_inode
2018-11-10 08:02:40 -05:00
mm: migrate: drop unused argument of migrate_page_move_mapping()
2018-12-28 12:11:51 -08:00
\n
2018-12-27 17:00:35 -08:00
iomap: wire up the iopoll method
2019-02-24 08:20:17 -07:00
aio: initialize kiocb private in case any filesystems expect it.
2019-02-06 08:04:22 -07:00
Remove 'type' argument from access_ok() function
2019-01-03 18:57:57 -08:00
exec: load_script: don't blindly truncate shebang string
2019-01-04 13:13:47 -08:00
block: add bio_set_polled() helper
2019-02-24 08:20:17 -07:00
Linux 5.0-rc6
2019-02-15 08:43:59 -07:00
dax fix 4.21
2018-12-31 09:46:39 -08:00
fs/dcache: Track & report number of negative dentries
2019-01-30 11:02:11 -08:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
2019-02-01 15:46:24 -08:00
Merge branch 'akpm' (patches from Andrew)
2019-01-05 09:16:18 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2019-01-05 13:18:59 -08:00
fs: add fget_many() and fput_many()
2019-02-28 08:24:23 -07:00
fs: add fget_many() and fput_many()
2019-02-28 08:24:23 -07:00
writeback: synchronize sync(2) against cgroup writeback membership switches
2019-01-22 14:39:38 -07:00
y2038: more syscalls and cleanups
2018-12-28 12:45:04 -08:00
io_uring: add support for pre-mapped user IO buffers
2019-02-28 08:24:23 -07:00
Remove 'type' argument from access_ok() function
2019-01-03 18:57:57 -08:00
iomap: wire up the iopoll method
2019-02-24 08:20:17 -07:00
locks: fix error in locks_move_blocks()
2019-01-02 20:14:50 -05:00
Add io_uring IO interface
2019-02-28 08:24:23 -07:00
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
2019-02-15 08:40:11 -07:00
Revert "vfs: Allow userns root to call mknod on owned filesystems."
2018-12-22 14:18:34 -08:00
Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2019-01-05 13:25:58 -08:00
vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled
2018-12-20 16:32:56 +00:00
Remove 'type' argument from access_ok() function
2019-01-03 18:57:57 -08:00
Remove 'type' argument from access_ok() function
2019-01-03 18:57:57 -08:00
Remove 'type' argument from access_ok() function
2019-01-03 18:57:57 -08:00
splice: don't read more than available pipe space
2018-12-04 08:50:49 -08:00
mount_fs: suppress MAC on MS_SUBMOUNT as well as MS_KERNMOUNT
2018-12-21 11:51:23 -05:00
userfaultfd: clear flag if remap event not enabled
2018-12-28 12:11:51 -08:00
edafccee56