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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /mm/page_io.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'mm/page_io.c')
-rw-r--r-- | mm/page_io.c | 533 |
1 files changed, 533 insertions, 0 deletions
diff --git a/mm/page_io.c b/mm/page_io.c new file mode 100644 index 000000000..233f6e6eb --- /dev/null +++ b/mm/page_io.c @@ -0,0 +1,533 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/mm/page_io.c + * + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * + * Swap reorganised 29.12.95, + * Asynchronous swapping added 30.12.95. Stephen Tweedie + * Removed race in async swapping. 14.4.1996. Bruno Haible + * Add swap of shared pages through the page cache. 20.2.1998. Stephen Tweedie + * Always use brw_page, life becomes simpler. 12 May 1998 Eric Biederman + */ + +#include <linux/mm.h> +#include <linux/kernel_stat.h> +#include <linux/gfp.h> +#include <linux/pagemap.h> +#include <linux/swap.h> +#include <linux/bio.h> +#include <linux/swapops.h> +#include <linux/buffer_head.h> +#include <linux/writeback.h> +#include <linux/frontswap.h> +#include <linux/blkdev.h> +#include <linux/psi.h> +#include <linux/uio.h> +#include <linux/sched/task.h> +#include <linux/delayacct.h> +#include "swap.h" + +static void end_swap_bio_write(struct bio *bio) +{ + struct page *page = bio_first_page_all(bio); + + if (bio->bi_status) { + SetPageError(page); + /* + * We failed to write the page out to swap-space. + * Re-dirty the page in order to avoid it being reclaimed. + * Also print a dire warning that things will go BAD (tm) + * very quickly. + * + * Also clear PG_reclaim to avoid folio_rotate_reclaimable() + */ + set_page_dirty(page); + pr_alert_ratelimited("Write-error on swap-device (%u:%u:%llu)\n", + MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)), + (unsigned long long)bio->bi_iter.bi_sector); + ClearPageReclaim(page); + } + end_page_writeback(page); + bio_put(bio); +} + +static void end_swap_bio_read(struct bio *bio) +{ + struct page *page = bio_first_page_all(bio); + struct task_struct *waiter = bio->bi_private; + + if (bio->bi_status) { + SetPageError(page); + ClearPageUptodate(page); + pr_alert_ratelimited("Read-error on swap-device (%u:%u:%llu)\n", + MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)), + (unsigned long long)bio->bi_iter.bi_sector); + goto out; + } + + SetPageUptodate(page); +out: + unlock_page(page); + WRITE_ONCE(bio->bi_private, NULL); + bio_put(bio); + if (waiter) { + blk_wake_io_task(waiter); + put_task_struct(waiter); + } +} + +int generic_swapfile_activate(struct swap_info_struct *sis, + struct file *swap_file, + sector_t *span) +{ + struct address_space *mapping = swap_file->f_mapping; + struct inode *inode = mapping->host; + unsigned blocks_per_page; + unsigned long page_no; + unsigned blkbits; + sector_t probe_block; + sector_t last_block; + sector_t lowest_block = -1; + sector_t highest_block = 0; + int nr_extents = 0; + int ret; + + blkbits = inode->i_blkbits; + blocks_per_page = PAGE_SIZE >> blkbits; + + /* + * Map all the blocks into the extent tree. This code doesn't try + * to be very smart. + */ + probe_block = 0; + page_no = 0; + last_block = i_size_read(inode) >> blkbits; + while ((probe_block + blocks_per_page) <= last_block && + page_no < sis->max) { + unsigned block_in_page; + sector_t first_block; + + cond_resched(); + + first_block = probe_block; + ret = bmap(inode, &first_block); + if (ret || !first_block) + goto bad_bmap; + + /* + * It must be PAGE_SIZE aligned on-disk + */ + if (first_block & (blocks_per_page - 1)) { + probe_block++; + goto reprobe; + } + + for (block_in_page = 1; block_in_page < blocks_per_page; + block_in_page++) { + sector_t block; + + block = probe_block + block_in_page; + ret = bmap(inode, &block); + if (ret || !block) + goto bad_bmap; + + if (block != first_block + block_in_page) { + /* Discontiguity */ + probe_block++; + goto reprobe; + } + } + + first_block >>= (PAGE_SHIFT - blkbits); + if (page_no) { /* exclude the header page */ + if (first_block < lowest_block) + lowest_block = first_block; + if (first_block > highest_block) + highest_block = first_block; + } + + /* + * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks + */ + ret = add_swap_extent(sis, page_no, 1, first_block); + if (ret < 0) + goto out; + nr_extents += ret; + page_no++; + probe_block += blocks_per_page; +reprobe: + continue; + } + ret = nr_extents; + *span = 1 + highest_block - lowest_block; + if (page_no == 0) + page_no = 1; /* force Empty message */ + sis->max = page_no; + sis->pages = page_no - 1; + sis->highest_bit = page_no - 1; +out: + return ret; +bad_bmap: + pr_err("swapon: swapfile has holes\n"); + ret = -EINVAL; + goto out; +} + +/* + * We may have stale swap cache pages in memory: notice + * them here and get rid of the unnecessary final write. + */ +int swap_writepage(struct page *page, struct writeback_control *wbc) +{ + struct folio *folio = page_folio(page); + int ret = 0; + + if (folio_free_swap(folio)) { + folio_unlock(folio); + goto out; + } + /* + * Arch code may have to preserve more data than just the page + * contents, e.g. memory tags. + */ + ret = arch_prepare_to_swap(&folio->page); + if (ret) { + folio_mark_dirty(folio); + folio_unlock(folio); + goto out; + } + if (frontswap_store(&folio->page) == 0) { + folio_start_writeback(folio); + folio_unlock(folio); + folio_end_writeback(folio); + goto out; + } + ret = __swap_writepage(&folio->page, wbc); +out: + return ret; +} + +static inline void count_swpout_vm_event(struct page *page) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (unlikely(PageTransHuge(page))) + count_vm_event(THP_SWPOUT); +#endif + count_vm_events(PSWPOUT, thp_nr_pages(page)); +} + +#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) +static void bio_associate_blkg_from_page(struct bio *bio, struct page *page) +{ + struct cgroup_subsys_state *css; + struct mem_cgroup *memcg; + + memcg = page_memcg(page); + if (!memcg) + return; + + rcu_read_lock(); + css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys); + bio_associate_blkg_from_css(bio, css); + rcu_read_unlock(); +} +#else +#define bio_associate_blkg_from_page(bio, page) do { } while (0) +#endif /* CONFIG_MEMCG && CONFIG_BLK_CGROUP */ + +struct swap_iocb { + struct kiocb iocb; + struct bio_vec bvec[SWAP_CLUSTER_MAX]; + int pages; + int len; +}; +static mempool_t *sio_pool; + +int sio_pool_init(void) +{ + if (!sio_pool) { + mempool_t *pool = mempool_create_kmalloc_pool( + SWAP_CLUSTER_MAX, sizeof(struct swap_iocb)); + if (cmpxchg(&sio_pool, NULL, pool)) + mempool_destroy(pool); + } + if (!sio_pool) + return -ENOMEM; + return 0; +} + +static void sio_write_complete(struct kiocb *iocb, long ret) +{ + struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb); + struct page *page = sio->bvec[0].bv_page; + int p; + + if (ret != sio->len) { + /* + * In the case of swap-over-nfs, this can be a + * temporary failure if the system has limited + * memory for allocating transmit buffers. + * Mark the page dirty and avoid + * folio_rotate_reclaimable but rate-limit the + * messages but do not flag PageError like + * the normal direct-to-bio case as it could + * be temporary. + */ + pr_err_ratelimited("Write error %ld on dio swapfile (%llu)\n", + ret, page_file_offset(page)); + for (p = 0; p < sio->pages; p++) { + page = sio->bvec[p].bv_page; + set_page_dirty(page); + ClearPageReclaim(page); + } + } else { + for (p = 0; p < sio->pages; p++) + count_swpout_vm_event(sio->bvec[p].bv_page); + } + + for (p = 0; p < sio->pages; p++) + end_page_writeback(sio->bvec[p].bv_page); + + mempool_free(sio, sio_pool); +} + +static int swap_writepage_fs(struct page *page, struct writeback_control *wbc) +{ + struct swap_iocb *sio = NULL; + struct swap_info_struct *sis = page_swap_info(page); + struct file *swap_file = sis->swap_file; + loff_t pos = page_file_offset(page); + + set_page_writeback(page); + unlock_page(page); + if (wbc->swap_plug) + sio = *wbc->swap_plug; + if (sio) { + if (sio->iocb.ki_filp != swap_file || + sio->iocb.ki_pos + sio->len != pos) { + swap_write_unplug(sio); + sio = NULL; + } + } + if (!sio) { + sio = mempool_alloc(sio_pool, GFP_NOIO); + init_sync_kiocb(&sio->iocb, swap_file); + sio->iocb.ki_complete = sio_write_complete; + sio->iocb.ki_pos = pos; + sio->pages = 0; + sio->len = 0; + } + bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0); + sio->len += thp_size(page); + sio->pages += 1; + if (sio->pages == ARRAY_SIZE(sio->bvec) || !wbc->swap_plug) { + swap_write_unplug(sio); + sio = NULL; + } + if (wbc->swap_plug) + *wbc->swap_plug = sio; + + return 0; +} + +int __swap_writepage(struct page *page, struct writeback_control *wbc) +{ + struct bio *bio; + int ret; + struct swap_info_struct *sis = page_swap_info(page); + + VM_BUG_ON_PAGE(!PageSwapCache(page), page); + /* + * ->flags can be updated non-atomicially (scan_swap_map_slots), + * but that will never affect SWP_FS_OPS, so the data_race + * is safe. + */ + if (data_race(sis->flags & SWP_FS_OPS)) + return swap_writepage_fs(page, wbc); + + ret = bdev_write_page(sis->bdev, swap_page_sector(page), page, wbc); + if (!ret) { + count_swpout_vm_event(page); + return 0; + } + + bio = bio_alloc(sis->bdev, 1, + REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc), + GFP_NOIO); + bio->bi_iter.bi_sector = swap_page_sector(page); + bio->bi_end_io = end_swap_bio_write; + bio_add_page(bio, page, thp_size(page), 0); + + bio_associate_blkg_from_page(bio, page); + count_swpout_vm_event(page); + set_page_writeback(page); + unlock_page(page); + submit_bio(bio); + + return 0; +} + +void swap_write_unplug(struct swap_iocb *sio) +{ + struct iov_iter from; + struct address_space *mapping = sio->iocb.ki_filp->f_mapping; + int ret; + + iov_iter_bvec(&from, ITER_SOURCE, sio->bvec, sio->pages, sio->len); + ret = mapping->a_ops->swap_rw(&sio->iocb, &from); + if (ret != -EIOCBQUEUED) + sio_write_complete(&sio->iocb, ret); +} + +static void sio_read_complete(struct kiocb *iocb, long ret) +{ + struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb); + int p; + + if (ret == sio->len) { + for (p = 0; p < sio->pages; p++) { + struct page *page = sio->bvec[p].bv_page; + + SetPageUptodate(page); + unlock_page(page); + } + count_vm_events(PSWPIN, sio->pages); + } else { + for (p = 0; p < sio->pages; p++) { + struct page *page = sio->bvec[p].bv_page; + + SetPageError(page); + ClearPageUptodate(page); + unlock_page(page); + } + pr_alert_ratelimited("Read-error on swap-device\n"); + } + mempool_free(sio, sio_pool); +} + +static void swap_readpage_fs(struct page *page, + struct swap_iocb **plug) +{ + struct swap_info_struct *sis = page_swap_info(page); + struct swap_iocb *sio = NULL; + loff_t pos = page_file_offset(page); + + if (plug) + sio = *plug; + if (sio) { + if (sio->iocb.ki_filp != sis->swap_file || + sio->iocb.ki_pos + sio->len != pos) { + swap_read_unplug(sio); + sio = NULL; + } + } + if (!sio) { + sio = mempool_alloc(sio_pool, GFP_KERNEL); + init_sync_kiocb(&sio->iocb, sis->swap_file); + sio->iocb.ki_pos = pos; + sio->iocb.ki_complete = sio_read_complete; + sio->pages = 0; + sio->len = 0; + } + bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0); + sio->len += thp_size(page); + sio->pages += 1; + if (sio->pages == ARRAY_SIZE(sio->bvec) || !plug) { + swap_read_unplug(sio); + sio = NULL; + } + if (plug) + *plug = sio; +} + +int swap_readpage(struct page *page, bool synchronous, + struct swap_iocb **plug) +{ + struct bio *bio; + int ret = 0; + struct swap_info_struct *sis = page_swap_info(page); + bool workingset = PageWorkingset(page); + unsigned long pflags; + bool in_thrashing; + + VM_BUG_ON_PAGE(!PageSwapCache(page) && !synchronous, page); + VM_BUG_ON_PAGE(!PageLocked(page), page); + VM_BUG_ON_PAGE(PageUptodate(page), page); + + /* + * Count submission time as memory stall and delay. When the device + * is congested, or the submitting cgroup IO-throttled, submission + * can be a significant part of overall IO time. + */ + if (workingset) { + delayacct_thrashing_start(&in_thrashing); + psi_memstall_enter(&pflags); + } + delayacct_swapin_start(); + + if (frontswap_load(page) == 0) { + SetPageUptodate(page); + unlock_page(page); + goto out; + } + + if (data_race(sis->flags & SWP_FS_OPS)) { + swap_readpage_fs(page, plug); + goto out; + } + + if (sis->flags & SWP_SYNCHRONOUS_IO) { + ret = bdev_read_page(sis->bdev, swap_page_sector(page), page); + if (!ret) { + count_vm_event(PSWPIN); + goto out; + } + } + + ret = 0; + bio = bio_alloc(sis->bdev, 1, REQ_OP_READ, GFP_KERNEL); + bio->bi_iter.bi_sector = swap_page_sector(page); + bio->bi_end_io = end_swap_bio_read; + bio_add_page(bio, page, thp_size(page), 0); + /* + * Keep this task valid during swap readpage because the oom killer may + * attempt to access it in the page fault retry time check. + */ + if (synchronous) { + get_task_struct(current); + bio->bi_private = current; + } + count_vm_event(PSWPIN); + bio_get(bio); + submit_bio(bio); + while (synchronous) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (!READ_ONCE(bio->bi_private)) + break; + + blk_io_schedule(); + } + __set_current_state(TASK_RUNNING); + bio_put(bio); + +out: + if (workingset) { + delayacct_thrashing_end(&in_thrashing); + psi_memstall_leave(&pflags); + } + delayacct_swapin_end(); + return ret; +} + +void __swap_read_unplug(struct swap_iocb *sio) +{ + struct iov_iter from; + struct address_space *mapping = sio->iocb.ki_filp->f_mapping; + int ret; + + iov_iter_bvec(&from, ITER_DEST, sio->bvec, sio->pages, sio->len); + ret = mapping->a_ops->swap_rw(&sio->iocb, &from); + if (ret != -EIOCBQUEUED) + sio_read_complete(&sio->iocb, ret); +} |