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* Merge tag 'vfs-6.8.iov_iter' of ↵Linus Torvalds2024-01-081-13/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs iov_iter cleanups from Christian Brauner: "This contains a minor cleanup. The patches drop an unused argument from import_single_range() allowing to replace import_single_range() with import_ubuf() and dropping import_single_range() completely" * tag 'vfs-6.8.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: iov_iter: replace import_single_range() with import_ubuf() iov_iter: remove unused 'iov' argument from import_single_range()
| * iov_iter: replace import_single_range() with import_ubuf()Jens Axboe2023-12-051-13/+0
| | | | | | | | | | | | | | | | | | | | With the removal of the 'iov' argument to import_single_range(), the two functions are now fully identical. Convert the import_single_range() callers to import_ubuf(), and remove the former fully. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20231204174827.1258875-3-axboe@kernel.dk Signed-off-by: Christian Brauner <brauner@kernel.org>
| * iov_iter: remove unused 'iov' argument from import_single_range()Jens Axboe2023-12-051-1/+1
| | | | | | | | | | | | | | | | It is entirely unused, just get rid of it. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20231204174827.1258875-2-axboe@kernel.dk Signed-off-by: Christian Brauner <brauner@kernel.org>
* | iov_iter: fix copy_page_to_iter_nofault()Omar Sandoval2023-11-181-1/+1
|/ | | | | | | | | | | | | | | | | The recent conversion to inline functions made two mistakes: 1. It tries to copy the full amount requested (bytes), not just what's available in the kmap'd page (n). 2. It's not applying the offset in the first page. Note that copy_page_to_iter_nofault() is only used by /proc/kcore. This was detected by drgn's test suite. Fixes: f1982740f5e7 ("iov_iter: Convert iterate*() to inline funcs") Signed-off-by: Omar Sandoval <osandov@fb.com> Link: https://lore.kernel.org/r/c1616e06b5248013cbbb1881bb4fef85a7a69ccb.1700257019.git.osandov@fb.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter, net: Move hash_and_copy_to_iter() to net/David Howells2023-10-091-20/+0
| | | | | | | | | | | | | | | | | | | | | | | Move hash_and_copy_to_iter() to be with its only caller in networking code. Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230925120309.1731676-13-dhowells@redhat.com cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <christian@brauner.io> cc: Matthew Wilcox <willy@infradead.org> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: David Laight <David.Laight@ACULAB.COM> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: Paolo Abeni <pabeni@redhat.com> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org cc: netdev@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter, net: Move csum_and_copy_to/from_iter() to net/David Howells2023-10-091-89/+0
| | | | | | | | | | | | | | | | | | | | | | | | Move csum_and_copy_to/from_iter() to net code now that the iteration framework can be #included. Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230925120309.1731676-10-dhowells@redhat.com cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <christian@brauner.io> cc: Matthew Wilcox <willy@infradead.org> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: David Laight <David.Laight@ACULAB.COM> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: Paolo Abeni <pabeni@redhat.com> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org cc: netdev@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter: Don't deal with iter->copy_mc in memcpy_from_iter_mc()David Howells2023-10-091-12/+23
| | | | | | | | | | | | | | | | | | | | | iter->copy_mc is only used with a bvec iterator and only by dump_emit_page() in fs/coredump.c so rather than handle this in memcpy_from_iter_mc() where it is checked repeatedly by _copy_from_iter() and copy_page_from_iter_atomic(), Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230925120309.1731676-9-dhowells@redhat.com cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <christian@brauner.io> cc: Matthew Wilcox <willy@infradead.org> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: David Laight <David.Laight@ACULAB.COM> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter: Convert iterate*() to inline funcsDavid Howells2023-09-251-241/+175
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert the iov_iter iteration macros to inline functions to make the code easier to follow. The functions are marked __always_inline as we don't want to end up with indirect calls in the code. This, however, leaves dealing with ->copy_mc in an awkard situation since the step function (memcpy_from_iter_mc()) needs to test the flag in the iterator, but isn't passed the iterator. This will be dealt with in a follow-up patch. The variable names in the per-type iterator functions have been harmonised as much as possible and made clearer as to the variable purpose. The iterator functions are also moved to a header file so that other operations that need to scan over an iterator can be added. For instance, the rbd driver could use this to scan a buffer to see if it is all zeros and libceph could use this to generate a crc. Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/3710261.1691764329@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/855.1692047347@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/20230816120741.534415-1-dhowells@redhat.com/ # v3 Link: https://lore.kernel.org/r/20230925120309.1731676-8-dhowells@redhat.com cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <christian@brauner.io> cc: Matthew Wilcox <willy@infradead.org> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: David Laight <David.Laight@ACULAB.COM> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter: Derive user-backedness from the iterator typeDavid Howells2023-09-251-1/+0
| | | | | | | | | | | | | | | | | | | | Use the iterator type to determine whether an iterator is user-backed or not rather than using a special flag for it. Now that ITER_UBUF and ITER_IOVEC are 0 and 1, they can be checked with a single comparison. Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230925120309.1731676-7-dhowells@redhat.com cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <christian@brauner.io> cc: Matthew Wilcox <willy@infradead.org> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: David Laight <David.Laight@ACULAB.COM> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* iov_iter: Fix iov_iter_extract_pages() with zero-sized entriesDavid Howells2023-09-101-15/+15
| | | | | | | | | | | | | | | | | | | | | iov_iter_extract_pages() doesn't correctly handle skipping over initial zero-length entries in ITER_KVEC and ITER_BVEC-type iterators. The problem is that it accidentally reduces maxsize to 0 when it skipping and thus runs to the end of the array and returns 0. Fix this by sticking the calculated size-to-copy in a new variable rather than back in maxsize. Fixes: 7d58fe731028 ("iov_iter: Add a function to extract a page list from an iterator") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Christian Brauner <brauner@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: David Hildenbrand <david@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'sound-6.6-rc1' of ↵Linus Torvalds2023-08-301-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound updates from Takashi Iwai: "We've received a fairly wide range of changes at this time, including for ALSA and ASoC core, but all of them are rather small changes. Here are some highlights: ALSA / ASoC Core: - Fixes of inconsistent locking around control API helpers - A few new control API functions and cleanups - Workarounds for potential UAFs by delayed kobj releases - Unified PCM copy ops with iov_iter - Continued efforts for ASoC API cleanups ASoC: - An adaptor to allow use of IIO DACs and ADCs in ASoC which pulls in some IIO changes - Create a library function for intlog10() and use it in the NAU8825 driver - Convert drivers to use the more modern maple tree register cache - Lots of work on the SOF framework, AMD and Intel drivers, including a lot of cleanup and new device support - Standardization of the presentation of jacks from drivers - Provision of some generic sound card DT properties - Support for AMD Van Gogh, AMD machines with MAX98388 and NAU8821, AWInic AW88261, Cirrus Logic CS35L36 and CS42L43, various Intel platforms including AVS machines with ES8336 and RT5663, Mediatek MT7986, NXP i.MX93, RealTek RT1017 and StarFive JH7110 Others: - New test coverage including ASoC and topology tests in KUnit; this also involves enabling UML builds of ALSA since that's the default KUnit test environment which pulls in the addition of some stubs to the driver - More enhancement of pcmtest driver - A few fixes / enhancements of MIDI 2.0 UMP core - Using PCI definitions in allover HD-audio code - Support for Cirrus CS35L56 and TI TAS2781 HD-audio sub-codecs - CS35L41 HD-audio sub-codec improvements - Continued emu10k1 improvements" * tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (693 commits) ALSA: pcm: Fix missing fixup call in compat hw_refine ioctl ASoC: dwc: i2s: Fix unused functions ALSA: usb-audio: Don't try to submit URBs after disconnection ALSA: emu10k1: add separate documentation for E-MU cards ALSA: emu10k1: more documentation updates ALSA: emu10k1: de-duplicate audigy-mixer.rst vs. sb-live-mixer.rst ALSA: ump: Fix -Wformat-truncation warnings ALSA: hda: Add missing dependency on CONFIG_EFI for Cirrus/TI sub-codecs ALSA: doc: Fix missing backquote in midi-2.0.rst ALSA: hda/realtek: Add quirk for mute LEDs on HP ENVY x360 15-eu0xxx ALSA: hda/tas2781: Switch back to use struct i2c_driver's .probe() ASoC: soc-core.c: Do not error if a DAI link component is not found ASoC: codecs: Fix error code in aw88261_i2c_probe() ASoC: audio-graph-card.c: move audio_graph_parse_of() ASoC: cs42l43: Use new-style PM runtime macros ALSA: documentation: Add description for USB MIDI 2.0 gadget driver ALSA: ump: Don't create unused substreams for static blocks ALSA: ump: Fill group names for legacy rawmidi substreams ALSA: usb-audio: Attach legacy rawmidi after probing all UMP EPs ALSA: ac97: Fix possible error value of *rac97 ...
| * iov_iter: Export import_ubuf()Takashi Iwai2023-08-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | Export import_ubuf() to be used in sound subsystem for generic memory handling as Linus suggested. It's used for constructing an iov_iter of a single segment user-space copy for PCM data. Cc: Alexander Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/CAHk-=wh-mUL6mp4chAc6E_UjwpPLyCPRCJK+iB4ZMD2BqjwGHA@mail.gmail.com Link: https://lore.kernel.org/r/20230815190136.8987-2-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | iov_iter: Add copy_folio_from_iter_atomic()Matthew Wilcox (Oracle)2023-07-251-1/+1
| | | | | | | | | | | | | | Add a folio wrapper around copy_page_from_iter_atomic(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
* | iov_iter: Handle compound highmem pages in copy_page_from_iter_atomic()Matthew Wilcox (Oracle)2023-07-251-10/+23
| | | | | | | | | | | | | | | | | | | | | | | | copy_page_from_iter_atomic() already handles !highmem compound pages correctly, but if we are passed a highmem compound page, each base page needs to be mapped & unmapped individually. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Tested-by: Kent Overstreet <kent.overstreet@linux.dev>
* | iov_iter: Map the page later in copy_page_from_iter_atomic()Matthew Wilcox (Oracle)2023-07-251-8/+8
|/ | | | | | | | | Remove a couple of calls to kunmap_atomic() in the rare error cases. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
* iov_iter: Mark copy_iovec_from_user() noclonePeter Zijlstra2023-07-101-1/+1
| | | | | | | | | | | | | | | | Extend commit 50f9a76ef127 ("iov_iter: Mark copy_compat_iovec_from_user() noinline") to also cover copy_iovec_from_user(). Different compiler versions cause the same problem on different functions. lib/iov_iter.o: warning: objtool: .altinstr_replacement+0x1f: redundant UACCESS disable lib/iov_iter.o: warning: objtool: iovec_from_user+0x84: call to copy_iovec_from_user.part.0() with UACCESS enabled lib/iov_iter.o: warning: objtool: __import_iovec+0x143: call to copy_iovec_from_user.part.0() with UACCESS enabled Fixes: 50f9a76ef127 ("iov_iter: Mark copy_compat_iovec_from_user() noinline") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lkml.kernel.org/r/20230616124354.GD4253@hirez.programming.kicks-ass.net
* iov_iter: remove iov_iter_get_pages and iov_iter_get_pages_allocChristoph Hellwig2023-06-161-28/+7
| | | | | | | | | | | Now that the direct I/O helpers have switched to use iov_iter_extract_pages, these helpers are unused. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Reviewed-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230614140341.521331-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* iov_iter: Kill ITER_PIPEDavid Howells2023-05-241-428/+3
| | | | | | | | | | | | | | | | | | | The ITER_PIPE-type iterator was only used by generic_file_splice_read() and that has been replaced and removed. This leaves ITER_PIPE unused - so remove it too. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: David Hildenbrand <david@redhat.com> cc: John Hubbard <jhubbard@nvidia.com> cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-31-dhowells@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* mm: hwpoison: coredump: support recovery from dump_user_range()Kefeng Wang2023-05-031-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dump_user_range() is used to copy the user page to a coredump file, but if a hardware memory error occurred during copy, which called from __kernel_write_iter() in dump_user_range(), it crashes, CPU: 112 PID: 7014 Comm: mca-recover Not tainted 6.3.0-rc2 #425 pc : __memcpy+0x110/0x260 lr : _copy_from_iter+0x3bc/0x4c8 ... Call trace: __memcpy+0x110/0x260 copy_page_from_iter+0xcc/0x130 pipe_write+0x164/0x6d8 __kernel_write_iter+0x9c/0x210 dump_user_range+0xc8/0x1d8 elf_core_dump+0x308/0x368 do_coredump+0x2e8/0xa40 get_signal+0x59c/0x788 do_signal+0x118/0x1f8 do_notify_resume+0xf0/0x280 el0_da+0x130/0x138 el0t_64_sync_handler+0x68/0xc0 el0t_64_sync+0x188/0x190 Generally, the '->write_iter' of file ops will use copy_page_from_iter() and copy_page_from_iter_atomic(), change memcpy() to copy_mc_to_kernel() in both of them to handle #MC during source read, which stop coredump processing and kill the task instead of kernel panic, but the source address may not always a user address, so introduce a new copy_mc flag in struct iov_iter{} to indicate that the iter could do a safe memory copy, also introduce the helpers to set/cleck the flag, for now, it's only used in coredump's dump_user_range(), but it could expand to any other scenarios to fix the similar issue. Link: https://lkml.kernel.org/r/20230417045323.11054-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Tong Tiangen <tongtiangen@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'mm-stable-2023-04-27-15-30' of ↵Linus Torvalds2023-04-281-0/+48
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of switching from a user process to a kernel thread. - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav. - zsmalloc performance improvements from Sergey Senozhatsky. - Yue Zhao has found and fixed some data race issues around the alteration of memcg userspace tunables. - VFS rationalizations from Christoph Hellwig: - removal of most of the callers of write_one_page() - make __filemap_get_folio()'s return value more useful - Luis Chamberlain has changed tmpfs so it no longer requires swap backing. Use `mount -o noswap'. - Qi Zheng has made the slab shrinkers operate locklessly, providing some scalability benefits. - Keith Busch has improved dmapool's performance, making part of its operations O(1) rather than O(n). - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd, permitting userspace to wr-protect anon memory unpopulated ptes. - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather than exclusive, and has fixed a bunch of errors which were caused by its unintuitive meaning. - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature, which causes minor faults to install a write-protected pte. - Vlastimil Babka has done some maintenance work on vma_merge(): cleanups to the kernel code and improvements to our userspace test harness. - Cleanups to do_fault_around() by Lorenzo Stoakes. - Mike Rapoport has moved a lot of initialization code out of various mm/ files and into mm/mm_init.c. - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for DRM, but DRM doesn't use it any more. - Lorenzo has also coverted read_kcore() and vread() to use iterators and has thereby removed the use of bounce buffers in some cases. - Lorenzo has also contributed further cleanups of vma_merge(). - Chaitanya Prakash provides some fixes to the mmap selftesting code. - Matthew Wilcox changes xfs and afs so they no longer take sleeping locks in ->map_page(), a step towards RCUification of pagefaults. - Suren Baghdasaryan has improved mmap_lock scalability by switching to per-VMA locking. - Frederic Weisbecker has reworked the percpu cache draining so that it no longer causes latency glitches on cpu isolated workloads. - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig logic. - Liu Shixin has changed zswap's initialization so we no longer waste a chunk of memory if zswap is not being used. - Yosry Ahmed has improved the performance of memcg statistics flushing. - David Stevens has fixed several issues involving khugepaged, userfaultfd and shmem. - Christoph Hellwig has provided some cleanup work to zram's IO-related code paths. - David Hildenbrand has fixed up some issues in the selftest code's testing of our pte state changing. - Pankaj Raghav has made page_endio() unneeded and has removed it. - Peter Xu contributed some rationalizations of the userfaultfd selftests. - Yosry Ahmed has fixed an issue around memcg's page recalim accounting. - Chaitanya Prakash has fixed some arm-related issues in the selftests/mm code. - Longlong Xia has improved the way in which KSM handles hwpoisoned pages. - Peter Xu fixes a few issues with uffd-wp at fork() time. - Stefan Roesch has changed KSM so that it may now be used on a per-process and per-cgroup basis. * tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm,unmap: avoid flushing TLB in batch if PTE is inaccessible shmem: restrict noswap option to initial user namespace mm/khugepaged: fix conflicting mods to collapse_file() sparse: remove unnecessary 0 values from rc mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area() hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() maple_tree: fix allocation in mas_sparse_area() mm: do not increment pgfault stats when page fault handler retries zsmalloc: allow only one active pool compaction context selftests/mm: add new selftests for KSM mm: add new KSM process and sysfs knobs mm: add new api to enable ksm per process mm: shrinkers: fix debugfs file permissions mm: don't check VMA write permissions if the PTE/PMD indicates write permissions migrate_pages_batch: fix statistics for longterm pin retry userfaultfd: use helper function range_in_vma() lib/show_mem.c: use for_each_populated_zone() simplify code mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() fs/buffer: convert create_page_buffers to folio_create_buffers fs/buffer: add folio_create_empty_buffers helper ...
| * iov_iter: add copy_page_to_iter_nofault()Lorenzo Stoakes2023-04-061-0/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a means to copy a page to user space from an iterator, aborting if a page fault would occur. This supports compound pages, but may be passed a tail page with an offset extending further into the compound page, so we cannot pass a folio. This allows for this function to be called from atomic context and _try_ to user pages if they are faulted in, aborting if not. The function does not use _copy_to_iter() in order to not specify might_fault(), this is similar to copy_page_from_iter_atomic(). This is being added in order that an iteratable form of vread() can be implemented while holding spinlocks. Link: https://lkml.kernel.org/r/19734729defb0f498a76bdec1bef3ac48a3af3e8.1679511146.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | iov: improve copy_iovec_from_user() code generationLinus Torvalds2023-04-241-9/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the same pattern as the compat version of this code does: instead of copying the whole array to a kernel buffer and then having a separate phase of verifying it, just do it one entry at a time, verifying as you go. On Jens' /dev/zero readv() test this improves performance by ~6%. [ This was obviously triggered by Jens' ITER_UBUF updates series ] Reported-and-tested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/all/de35d11d-bce7-e976-7372-1f2caf417103@kernel.dk/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | iov_iter: Mark copy_compat_iovec_from_user() noinlineJosh Poimboeuf2023-04-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 6376ce56feb6 ("iov_iter: import single vector iovecs as ITER_UBUF"), GCC does an inter-procedural compiler optimization which moves the user_access_begin() out of copy_compat_iovec_from_user() and into its callers: lib/iov_iter.o: warning: objtool: .altinstr_replacement+0x0: redundant UACCESS disable lib/iov_iter.o: warning: objtool: iovec_from_user.part.0+0xc7: call to copy_compat_iovec_from_user.part.0() with UACCESS enabled lib/iov_iter.o: warning: objtool: __import_iovec+0x21d: call to copy_compat_iovec_from_user.part.0() with UACCESS enabled Enforce the "no UACCESS enable across function boundaries" rule by disabling cloning for copy_compat_iovec_from_user(). Fixes: 6376ce56feb6 ("iov_iter: import single vector iovecs as ITER_UBUF") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> https://lkml.kernel.org/lkml/20230327120017.6bb826d7@canb.auug.org.au Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Tested-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | iov_iter: import single vector iovecs as ITER_UBUFJens Axboe2023-03-301-0/+27
| | | | | | | | | | | | | | | | | | Add a special case to __import_iovec(), which imports a single segment iovec as an ITER_UBUF rather than an ITER_IOVEC. ITER_UBUF is cheaper to iterate than ITER_IOVEC, and for a single segment iovec, there's no point in using a segmented iterator. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | iov_iter: convert import_single_range() to ITER_UBUFJens Axboe2023-03-301-3/+1
| | | | | | | | | | | | | | | | Since we're just importing a single vector, we don't have to turn it into an ITER_IOVEC. Instead turn it into an ITER_UBUF, which is cheaper to iterate. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | iov_iter: add iter_iovec() helperJens Axboe2023-03-301-26/+30
|/ | | | | | | | | | | | This returns a pointer to the current iovec entry in the iterator. Only useful with ITER_IOVEC right now, but it prepares us to treat ITER_UBUF and ITER_IOVEC identically for the first segment. Rename struct iov_iter->iov to iov_iter->__iov to find any potentially troublesome spots, and also to prevent anyone from adding new code that accesses iter->iov directly. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag '6.3-rc-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2023-02-231-12/+272
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull cifs client updates from Steve French: "The largest subset of this is from David Howells et al: making the cifs/smb3 driver pass iov_iters down to the lowest layers, directly to the network transport rather than passing lists of pages around, helping multiple areas: - Pin user pages, thereby fixing the race between concurrent DIO read and fork, where the pages containing the DIO read buffer may end up belonging to the child process and not the parent - with the result that the parent might not see the retrieved data. - cifs shouldn't take refs on pages extracted from non-user-backed iterators (eg. KVEC). With these changes, cifs will apply the appropriate cleanup. - Making it easier to transition to using folios in cifs rather than pages by dealing with them through BVEC and XARRAY iterators. - Allowing cifs to use the new splice function The remainder are: - fixes for stable, including various fixes for uninitialized memory, wrong length field causing mount issue to very old servers, important directory lease fixes and reconnect fixes - cleanups (unused code removal, change one element array usage, and a change form strtobool to kstrtobool, and Kconfig cleanups) - SMBDIRECT (RDMA) fixes including iov_iter integration and UAF fixes - reconnect fixes - multichannel fixes, including improving channel allocation (to least used channel) - remove the last use of lock_page_killable by moving to folio_lock_killable" * tag '6.3-rc-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: (46 commits) update internal module version number for cifs.ko cifs: update ip_addr for ses only for primary chan setup cifs: use tcon allocation functions even for dummy tcon cifs: use the least loaded channel for sending requests cifs: DIO to/from KVEC-type iterators should now work cifs: Remove unused code cifs: Build the RDMA SGE list directly from an iterator cifs: Change the I/O paths to use an iterator rather than a page list cifs: Add a function to read into an iter from a socket cifs: Add some helper functions cifs: Add a function to Hash the contents of an iterator cifs: Add a function to build an RDMA SGE list from an iterator netfs: Add a function to extract an iterator into a scatterlist netfs: Add a function to extract a UBUF or IOVEC into a BVEC iterator cifs: Implement splice_read to pass down ITER_BVEC not ITER_PIPE splice: Export filemap/direct_splice_read() iov_iter: Add a function to extract a page list from an iterator iov_iter: Define flags to qualify page extraction. splice: Add a func to do a splice from an O_DIRECT file without ITER_PIPE splice: Add a func to do a splice from a buffered file without ITER_PIPE ...
| * iov_iter: Add a function to extract a page list from an iteratorDavid Howells2023-02-211-0/+264
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a function, iov_iter_extract_pages(), to extract a list of pages from an iterator. The pages may be returned with a pin added or nothing, depending on the type of iterator. Add a second function, iov_iter_extract_will_pin(), to determine how the cleanup should be done. There are two cases: (1) ITER_IOVEC or ITER_UBUF iterator. Extracted pages will have pins (FOLL_PIN) obtained on them so that a concurrent fork() will forcibly copy the page so that DMA is done to/from the parent's buffer and is unavailable to/unaffected by the child process. iov_iter_extract_will_pin() will return true for this case. The caller should use something like unpin_user_page() to dispose of the page. (2) Any other sort of iterator. No refs or pins are obtained on the page, the assumption is made that the caller will manage page retention. iov_iter_extract_will_pin() will return false. The pages don't need additional disposal. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: John Hubbard <jhubbard@nvidia.com> cc: David Hildenbrand <david@redhat.com> cc: Matthew Wilcox <willy@infradead.org> cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Signed-off-by: Steve French <stfrench@microsoft.com>
| * iov_iter: Define flags to qualify page extraction.David Howells2023-02-211-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Define flags to qualify page extraction to pass into iov_iter_*_pages*() rather than passing in FOLL_* flags. For now only a flag to allow peer-to-peer DMA is supported. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: Logan Gunthorpe <logang@deltatee.com> cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
| * splice: Add a func to do a splice from a buffered file without ITER_PIPEDavid Howells2023-02-211-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a function to do splice read from a buffered file, pulling the folios out of the pagecache directly by calling filemap_get_pages() to do any required reading and then pasting the returned folios into the pipe. A helper function is provided to do the actual folio pasting and will handle multipage folios by splicing as many of the relevant subpages as will fit into the pipe. The code is loosely based on filemap_read() and might belong in mm/filemap.c with that as it needs to use filemap_get_pages(). Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> cc: Christoph Hellwig <hch@lst.de> cc: Al Viro <viro@zeniv.linux.org.uk> cc: David Hildenbrand <david@redhat.com> cc: John Hubbard <jhubbard@nvidia.com> cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
* | iov_iter: move iter_ubuf check inside restore WARNKeith Busch2023-01-091-2/+2
| | | | | | | | | | | | | | | | | | | | io_uring is using iter_ubuf types for single vector requests. We expect state restore may happen for this type now, and it is already handled correctly, so suppress the warning. Signed-off-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Christoph Hellwig <hch@lst.de>
* | iov: add import_ubuf()Jens Axboe2023-01-091-0/+11
|/ | | | | | | | Like import_single_range(), but for ITER_UBUF. Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
* Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linuxLinus Torvalds2022-12-131-8/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block updates from Jens Axboe: - NVMe pull requests via Christoph: - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan Joshi) - Refactor PCIe probing and reset (Christoph Hellwig) - Various fabrics authentication fixes and improvements (Sagi Grimberg) - Avoid fallback to sequential scan due to transient issues (Uday Shankar) - Implement support for the DEAC bit in Write Zeroes (Christoph Hellwig) - Allow overriding the IEEE OUI and firmware revision in configfs for nvmet (Aleksandr Miloserdov) - Force reconnect when number of queue changes in nvmet (Daniel Wagner) - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi Grimberg, Christoph Hellwig, Christophe JAILLET) - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni) - Use the common tagset helpers in nvme-pci driver (Christoph Hellwig) - Cleanup the nvme-pci removal path (Christoph Hellwig) - Use kstrtobool() instead of strtobool (Christophe JAILLET) - Allow unprivileged passthrough of Identify Controller (Joel Granados) - Support io stats on the mpath device (Sagi Grimberg) - Minor nvmet cleanup (Sagi Grimberg) - MD pull requests via Song: - Code cleanups (Christoph) - Various fixes - Floppy pull request from Denis: - Fix a memory leak in the init error path (Yuan) - Series fixing some batch wakeup issues with sbitmap (Gabriel) - Removal of the pktcdvd driver that was deprecated more than 5 years ago, and subsequent removal of the devnode callback in struct block_device_operations as no users are now left (Greg) - Fix for partition read on an exclusively opened bdev (Jan) - Series of elevator API cleanups (Jinlong, Christoph) - Series of fixes and cleanups for blk-iocost (Kemeng) - Series of fixes and cleanups for blk-throttle (Kemeng) - Series adding concurrent support for sync queues in BFQ (Yu) - Series bringing drbd a bit closer to the out-of-tree maintained version (Christian, Joel, Lars, Philipp) - Misc drbd fixes (Wang) - blk-wbt fixes and tweaks for enable/disable (Yu) - Fixes for mq-deadline for zoned devices (Damien) - Add support for read-only and offline zones for null_blk (Shin'ichiro) - Series fixing the delayed holder tracking, as used by DM (Yu, Christoph) - Series enabling bio alloc caching for IRQ based IO (Pavel) - Series enabling userspace peer-to-peer DMA (Logan) - BFQ waker fixes (Khazhismel) - Series fixing elevator refcount issues (Christoph, Jinlong) - Series cleaning up references around queue destruction (Christoph) - Series doing quiesce by tagset, enabling cleanups in drivers (Christoph, Chao) - Series untangling the queue kobject and queue references (Christoph) - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye, Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph) * tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits) blktrace: Fix output non-blktrace event when blk_classic option enabled block: sed-opal: Don't include <linux/kernel.h> sed-opal: allow using IOC_OPAL_SAVE for locking too blk-cgroup: Fix typo in comment block: remove bio_set_op_attrs nvmet: don't open-code NVME_NS_ATTR_RO enumeration nvme-pci: use the tagset alloc/free helpers nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers nvme: consolidate setting the tagset flags nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set block: bio_copy_data_iter nvme-pci: split out a nvme_pci_ctrl_is_dead helper nvme-pci: return early on ctrl state mismatch in nvme_reset_work nvme-pci: rename nvme_disable_io_queues nvme-pci: cleanup nvme_suspend_queue nvme-pci: remove nvme_pci_disable nvme-pci: remove nvme_disable_admin_queue nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl nvme: use nvme_wait_ready in nvme_shutdown_ctrl ...
| * iov_iter: introduce iov_iter_get_pages_[alloc_]flags()Logan Gunthorpe2022-11-091-8/+24
| | | | | | | | | | | | | | | | | | | | | | | | Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags() which take a flags argument that is passed to get_user_pages_fast(). This is so that FOLL_PCI_P2PDMA can be passed when appropriate. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20221021174116.7200-4-logang@deltatee.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | iov_iter: saner checks for attempt to copy to/from iteratorAl Viro2022-11-251-14/+17
| | | | | | | | | | | | | | | | instead of "don't do it to ITER_PIPE" check for ->data_source being false on copying from iterator. Check for !->data_source for copying to iterator, while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | csum_and_copy_to_iter(): handle ITER_DISCARDAl Viro2022-11-251-2/+6
| | | | | | | | | | | | | | | | Not hard to implement - we are not copying anything here, so csum_and_memcpy() is not usable, but calculating a checksum of source directly is trivial... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | get rid of unlikely() on page_copy_sane() callsAl Viro2022-11-251-6/+5
|/ | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* instrumented.h: allow instrumenting both sides of copy_from_user()Alexander Potapenko2022-10-031-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce instrument_copy_from_user_before() and instrument_copy_from_user_after() hooks to be invoked before and after the call to copy_from_user(). KASAN and KCSAN will be only using instrument_copy_from_user_before(), but for KMSAN we'll need to insert code after copy_from_user(). Link: https://lkml.kernel.org/r/20220915150417.722975-4-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* fix copy_page_from_iter() for compound destinationsAl Viro2022-08-091-4/+18
| | | | | | | had been broken for ITER_BVEC et.al. since ever (OK, v3.17 when ITER_BVEC had first appeared)... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* copy_page_to_iter(): don't split high-order page in case of ITER_PIPEAl Viro2022-08-091-15/+6
| | | | | | ... just shove it into one pipe_buffer. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* expand those iov_iter_advance()...Al Viro2022-08-091-2/+9
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* pipe_get_pages(): switch to append_pipe()Al Viro2022-08-091-29/+6
| | | | | | | | now that we are advancing the iterator, there's no need to treat the first page separately - just call append_pipe() in a loop. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* get rid of non-advancing variantsAl Viro2022-08-091-9/+18
| | | | | | | mechanical change; will be further massaged in subsequent commits Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* iov_iter: saner helper for page array allocationAl Viro2022-08-091-45/+32
| | | | | | | | | | | | All call sites of get_pages_array() are essenitally identical now. Replace with common helper... Returns number of slots available in resulting array or 0 on OOM; it's up to the caller to make sure it doesn't ask to zero-entry array (i.e. neither maxpages nor size are allowed to be zero). Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fold __pipe_get_pages() into pipe_get_pages()Al Viro2022-08-091-37/+38
| | | | | | | | | | | | | | | | ... and don't mangle maxsize there - turn the loop into counting one instead. Easier to see that we won't run out of array that way. Note that special treatment of the partial buffer in that thing is an artifact of the non-advancing semantics of iov_iter_get_pages() - if not for that, it would be append_pipe(), same as the body of the loop that follows it. IOW, once we make iov_iter_get_pages() advancing, the whole thing will turn into calculate how many pages do we want allocate an array (if needed) call append_pipe() that many times. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ITER_XARRAY: don't open-code DIV_ROUND_UP()Al Viro2022-08-091-9/+1
| | | | | Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() gutsAl Viro2022-08-091-59/+27
| | | | | | | same as for pipes and xarrays; after that iov_iter_get_pages() becomes a wrapper for __iov_iter_get_pages_alloc(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* unify xarray_get_pages() and xarray_get_pages_alloc()Al Viro2022-08-091-39/+10
| | | | | | | same as for pipes Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* unify pipe_get_pages() and pipe_get_pages_alloc()Al Viro2022-08-091-32/+17
| | | | | | | | | | | | | | | | The differences between those two are * pipe_get_pages() gets a non-NULL struct page ** value pointing to preallocated array + array size. * pipe_get_pages_alloc() gets an address of struct page ** variable that contains NULL, allocates the array and (on success) stores its address in that variable. Not hard to combine - always pass struct page ***, have the previous pipe_get_pages_alloc() caller pass ~0U as cap for array size. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* iov_iter_get_pages(): sanity-check argumentsAl Viro2022-08-091-7/+2
| | | | | | | | | | zero maxpages is bogus, but best treated as "just return 0"; NULL pages, OTOH, should be treated as a hard bug. get rid of now completely useless checks in xarray_get_pages{,_alloc}(). Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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