From dd05add7b2b6004c5fa3a1f276f56d8668f86b65 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Sat, 26 Sep 2026 19:20:30 -0300 Subject: netfs: zero the tail of a short DIO/unbuffered read The buffered read collector zero-fills the tail of a short read that stops below the inode's i_size (netfs_clear_unread()), so a read that races an extending write still returns the expected number of bytes. The non-buffered collector path does no such thing: it just records how much was transferred. Add the same zero-fill for the non-buffered case, gated on NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short result from it is known to be safe to treat as a hole, as opposed to NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of the file and should be reported short as-is. Only CLEAR_TAIL should zero-fill here; a real EOF must stay a real short read. No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest, so this is inert on its own -- a following change teaches cifs to set it in the one case that needs it. Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item") Reviewed-by: David Howells Reviewed-by: Namjae Jeon Signed-off-by: Paulo Alcantara Cc: Christian Brauner Cc: Matthew Wilcox Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- drivers/md/raid5-log.h | 151 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 151 insertions(+) create mode 100644 drivers/md/raid5-log.h (limited to 'drivers/md/raid5-log.h') diff --git a/drivers/md/raid5-log.h b/drivers/md/raid5-log.h new file mode 100644 index 000000000..c83325026 --- /dev/null +++ b/drivers/md/raid5-log.h @@ -0,0 +1,151 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _RAID5_LOG_H +#define _RAID5_LOG_H + +int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev); +void r5l_exit_log(struct r5conf *conf); +int r5l_write_stripe(struct r5l_log *log, struct stripe_head *head_sh); +void r5l_write_stripe_run(struct r5l_log *log); +void r5l_flush_stripe_to_raid(struct r5l_log *log); +void r5l_stripe_write_finished(struct stripe_head *sh); +int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio); +void r5l_quiesce(struct r5l_log *log, int quiesce); +bool r5l_log_disk_error(struct r5conf *conf); +bool r5c_is_writeback(struct r5l_log *log); +int r5c_try_caching_write(struct r5conf *conf, struct stripe_head *sh, + struct stripe_head_state *s, int disks); +void r5c_finish_stripe_write_out(struct r5conf *conf, struct stripe_head *sh, + struct stripe_head_state *s); +void r5c_release_extra_page(struct stripe_head *sh); +void r5c_use_extra_page(struct stripe_head *sh); +void r5l_wake_reclaim(struct r5l_log *log, sector_t space); +void r5c_handle_cached_data_endio(struct r5conf *conf, + struct stripe_head *sh, int disks); +int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh); +void r5c_make_stripe_write_out(struct stripe_head *sh); +void r5c_flush_cache(struct r5conf *conf, int num); +void r5c_check_stripe_cache_usage(struct r5conf *conf); +void r5c_check_cached_full_stripe(struct r5conf *conf); +extern struct md_sysfs_entry r5c_journal_mode; +void r5c_update_on_rdev_error(struct mddev *mddev, struct md_rdev *rdev); +bool r5c_big_stripe_cached(struct r5conf *conf, sector_t sect); +int r5l_start(struct r5l_log *log); + +struct dma_async_tx_descriptor * +ops_run_partial_parity(struct stripe_head *sh, struct raid5_percpu *percpu, + struct dma_async_tx_descriptor *tx); +int ppl_init_log(struct r5conf *conf); +void ppl_exit_log(struct r5conf *conf); +int ppl_write_stripe(struct r5conf *conf, struct stripe_head *sh); +void ppl_write_stripe_run(struct r5conf *conf); +void ppl_stripe_write_finished(struct stripe_head *sh); +int ppl_modify_log(struct r5conf *conf, struct md_rdev *rdev, bool add); +void ppl_quiesce(struct r5conf *conf, int quiesce); +int ppl_handle_flush_request(struct bio *bio); +extern struct md_sysfs_entry ppl_write_hint; + +static inline bool raid5_has_log(struct r5conf *conf) +{ + return test_bit(MD_HAS_JOURNAL, &conf->mddev->flags); +} + +static inline bool raid5_has_ppl(struct r5conf *conf) +{ + return test_bit(MD_HAS_PPL, &conf->mddev->flags); +} + +static inline int log_stripe(struct stripe_head *sh, struct stripe_head_state *s) +{ + struct r5conf *conf = sh->raid_conf; + + if (conf->log) { + if (!test_bit(STRIPE_R5C_CACHING, &sh->state)) { + /* writing out phase */ + if (s->waiting_extra_page) + return 0; + return r5l_write_stripe(conf->log, sh); + } else if (test_bit(STRIPE_LOG_TRAPPED, &sh->state)) { + /* caching phase */ + return r5c_cache_data(conf->log, sh); + } + } else if (raid5_has_ppl(conf)) { + return ppl_write_stripe(conf, sh); + } + + return -EAGAIN; +} + +static inline void log_stripe_write_finished(struct stripe_head *sh) +{ + struct r5conf *conf = sh->raid_conf; + + if (conf->log) + r5l_stripe_write_finished(sh); + else if (raid5_has_ppl(conf)) + ppl_stripe_write_finished(sh); +} + +static inline void log_write_stripe_run(struct r5conf *conf) +{ + if (conf->log) + r5l_write_stripe_run(conf->log); + else if (raid5_has_ppl(conf)) + ppl_write_stripe_run(conf); +} + +static inline void log_flush_stripe_to_raid(struct r5conf *conf) +{ + if (conf->log) + r5l_flush_stripe_to_raid(conf->log); + else if (raid5_has_ppl(conf)) + ppl_write_stripe_run(conf); +} + +static inline int log_handle_flush_request(struct r5conf *conf, struct bio *bio) +{ + int ret = -ENODEV; + + if (conf->log) + ret = r5l_handle_flush_request(conf->log, bio); + else if (raid5_has_ppl(conf)) + ret = ppl_handle_flush_request(bio); + + return ret; +} + +static inline void log_quiesce(struct r5conf *conf, int quiesce) +{ + if (conf->log) + r5l_quiesce(conf->log, quiesce); + else if (raid5_has_ppl(conf)) + ppl_quiesce(conf, quiesce); +} + +static inline void log_exit(struct r5conf *conf) +{ + if (conf->log) + r5l_exit_log(conf); + else if (raid5_has_ppl(conf)) + ppl_exit_log(conf); +} + +static inline int log_init(struct r5conf *conf, struct md_rdev *journal_dev, + bool ppl) +{ + if (journal_dev) + return r5l_init_log(conf, journal_dev); + else if (ppl) + return ppl_init_log(conf); + + return 0; +} + +static inline int log_modify(struct r5conf *conf, struct md_rdev *rdev, bool add) +{ + if (raid5_has_ppl(conf)) + return ppl_modify_log(conf, rdev, add); + + return 0; +} + +#endif -- cgit v1.3.1