The patch titled Subject: md: convert to kvmalloc has been added to the -mm tree. Its filename is md-convert-to-kvmalloc.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/md-convert-to-kvmalloc.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/md-convert-to-kvmalloc.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Kent Overstreet <kent.overstreet@xxxxxxxxx> Subject: md: convert to kvmalloc The code really just wants a big flat buffer, so just do that. Link: http://lkml.kernel.org/r/20181217131929.11727-3-kent.overstreet@xxxxxxxxx Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx> Reviewed-by: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Shaohua Li <shli@xxxxxxxxxx> Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Eric Paris <eparis@xxxxxxxxxxxxxx> Cc: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> Cc: Neil Horman <nhorman@xxxxxxxxxxxxx> Cc: Paul Moore <paul@xxxxxxxxxxxxxx> Cc: Pravin B Shelar <pshelar@xxxxxxx> Cc: Stephen Smalley <sds@xxxxxxxxxxxxx> Cc: Vlad Yasevich <vyasevich@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/md/raid5-ppl.c | 6 -- drivers/md/raid5.c | 85 +++++++++++++++++---------------------- drivers/md/raid5.h | 9 ++-- 3 files changed, 45 insertions(+), 55 deletions(-) --- a/drivers/md/raid5.c~md-convert-to-kvmalloc +++ a/drivers/md/raid5.c @@ -54,7 +54,6 @@ #include <linux/slab.h> #include <linux/ratelimit.h> #include <linux/nodemask.h> -#include <linux/flex_array.h> #include <trace/events/block.h> #include <linux/list_sort.h> @@ -1394,22 +1393,16 @@ static void ops_complete_compute(void *s } /* return a pointer to the address conversion region of the scribble buffer */ -static addr_conv_t *to_addr_conv(struct stripe_head *sh, - struct raid5_percpu *percpu, int i) +static struct page **to_addr_page(struct raid5_percpu *percpu, int i) { - void *addr; - - addr = flex_array_get(percpu->scribble, i); - return addr + sizeof(struct page *) * (sh->disks + 2); + return percpu->scribble + i * percpu->scribble_obj_size; } /* return a pointer to the address conversion region of the scribble buffer */ -static struct page **to_addr_page(struct raid5_percpu *percpu, int i) +static addr_conv_t *to_addr_conv(struct stripe_head *sh, + struct raid5_percpu *percpu, int i) { - void *addr; - - addr = flex_array_get(percpu->scribble, i); - return addr; + return (void *) (to_addr_page(percpu, i) + sh->disks + 2); } static struct dma_async_tx_descriptor * @@ -2238,21 +2231,23 @@ static int grow_stripes(struct r5conf *c * calculate over all devices (not just the data blocks), using zeros in place * of the P and Q blocks. */ -static struct flex_array *scribble_alloc(int num, int cnt, gfp_t flags) +static int scribble_alloc(struct raid5_percpu *percpu, + int num, int cnt, gfp_t flags) { - struct flex_array *ret; - size_t len; + size_t obj_size = + sizeof(struct page *) * (num+2) + + sizeof(addr_conv_t) * (num+2); + void *scribble; - len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2); - ret = flex_array_alloc(len, cnt, flags); - if (!ret) - return NULL; - /* always prealloc all elements, so no locking is required */ - if (flex_array_prealloc(ret, 0, cnt, flags)) { - flex_array_free(ret); - return NULL; - } - return ret; + scribble = kvmalloc_array(cnt, obj_size, flags); + if (!scribble) + return -ENOMEM; + + kvfree(percpu->scribble); + + percpu->scribble = scribble; + percpu->scribble_obj_size = obj_size; + return 0; } static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors) @@ -2270,23 +2265,18 @@ static int resize_chunks(struct r5conf * return 0; mddev_suspend(conf->mddev); get_online_cpus(); + for_each_present_cpu(cpu) { struct raid5_percpu *percpu; - struct flex_array *scribble; percpu = per_cpu_ptr(conf->percpu, cpu); - scribble = scribble_alloc(new_disks, - new_sectors / STRIPE_SECTORS, - GFP_NOIO); - - if (scribble) { - flex_array_free(percpu->scribble); - percpu->scribble = scribble; - } else { - err = -ENOMEM; + err = scribble_alloc(percpu, new_disks, + new_sectors / STRIPE_SECTORS, + GFP_NOIO); + if (err) break; - } } + put_online_cpus(); mddev_resume(conf->mddev); if (!err) { @@ -6738,25 +6728,26 @@ raid5_size(struct mddev *mddev, sector_t static void free_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu) { safe_put_page(percpu->spare_page); - if (percpu->scribble) - flex_array_free(percpu->scribble); percpu->spare_page = NULL; + kvfree(percpu->scribble); percpu->scribble = NULL; } static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu) { - if (conf->level == 6 && !percpu->spare_page) + if (conf->level == 6 && !percpu->spare_page) { percpu->spare_page = alloc_page(GFP_KERNEL); - if (!percpu->scribble) - percpu->scribble = scribble_alloc(max(conf->raid_disks, - conf->previous_raid_disks), - max(conf->chunk_sectors, - conf->prev_chunk_sectors) - / STRIPE_SECTORS, - GFP_KERNEL); + if (!percpu->spare_page) + return -ENOMEM; + } - if (!percpu->scribble || (conf->level == 6 && !percpu->spare_page)) { + if (scribble_alloc(percpu, + max(conf->raid_disks, + conf->previous_raid_disks), + max(conf->chunk_sectors, + conf->prev_chunk_sectors) + / STRIPE_SECTORS, + GFP_KERNEL)) { free_scratch_buffer(conf, percpu); return -ENOMEM; } --- a/drivers/md/raid5.h~md-convert-to-kvmalloc +++ a/drivers/md/raid5.h @@ -638,10 +638,11 @@ struct r5conf { /* per cpu variables */ struct raid5_percpu { struct page *spare_page; /* Used when checking P/Q in raid6 */ - struct flex_array *scribble; /* space for constructing buffer - * lists and performing address - * conversions - */ + void *scribble; /* space for constructing buffer + * lists and performing address + * conversions + */ + int scribble_obj_size; } __percpu *percpu; int scribble_disks; int scribble_sectors; --- a/drivers/md/raid5-ppl.c~md-convert-to-kvmalloc +++ a/drivers/md/raid5-ppl.c @@ -16,7 +16,6 @@ #include <linux/blkdev.h> #include <linux/slab.h> #include <linux/crc32c.h> -#include <linux/flex_array.h> #include <linux/async_tx.h> #include <linux/raid/md_p.h> #include "md.h" @@ -165,7 +164,7 @@ ops_run_partial_parity(struct stripe_hea struct dma_async_tx_descriptor *tx) { int disks = sh->disks; - struct page **srcs = flex_array_get(percpu->scribble, 0); + struct page **srcs = percpu->scribble; int count = 0, pd_idx = sh->pd_idx, i; struct async_submit_ctl submit; @@ -196,8 +195,7 @@ ops_run_partial_parity(struct stripe_hea } init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, tx, - NULL, sh, flex_array_get(percpu->scribble, 0) - + sizeof(struct page *) * (sh->disks + 2)); + NULL, sh, (void *) (srcs + sh->disks + 2)); if (count == 1) tx = async_memcpy(sh->ppl_page, srcs[0], 0, 0, PAGE_SIZE, _ Patches currently in -mm which might be from kent.overstreet@xxxxxxxxx are openvswitch-convert-to-kvmalloc.patch md-convert-to-kvmalloc.patch selinux-convert-to-kvmalloc.patch generic-radix-trees.patch proc-commit-to-genradix.patch sctp-convert-to-genradix.patch drop-flex_arrays.patch