diff options
Diffstat (limited to 'drivers/block/zram/zram_drv.c')
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index b09acdb753ee..f92965c4229b 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -650,7 +650,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, { int ret = 0; size_t clen; - unsigned long handle; + unsigned long handle = 0; struct page *page; unsigned char *user_mem, *cmem, *src, *uncmem = NULL; struct zram_meta *meta = zram->meta; @@ -673,9 +673,8 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, goto out; } - zstrm = zcomp_strm_find(zram->comp); +compress_again: user_mem = kmap_atomic(page); - if (is_partial_io(bvec)) { memcpy(uncmem + offset, user_mem + bvec->bv_offset, bvec->bv_len); @@ -699,6 +698,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, goto out; } + zstrm = zcomp_strm_find(zram->comp); ret = zcomp_compress(zram->comp, zstrm, uncmem, &clen); if (!is_partial_io(bvec)) { kunmap_atomic(user_mem); @@ -710,6 +710,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, pr_err("Compression failed! err=%d\n", ret); goto out; } + src = zstrm->buffer; if (unlikely(clen > max_zpage_size)) { clen = PAGE_SIZE; @@ -717,8 +718,33 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, src = uncmem; } - handle = zs_malloc(meta->mem_pool, clen, GFP_NOIO | __GFP_HIGHMEM); + /* + * handle allocation has 2 paths: + * a) fast path is executed with preemption disabled (for + * per-cpu streams) and has __GFP_DIRECT_RECLAIM bit clear, + * since we can't sleep; + * b) slow path enables preemption and attempts to allocate + * the page with __GFP_DIRECT_RECLAIM bit set. we have to + * put per-cpu compression stream and, thus, to re-do + * the compression once handle is allocated. + * + * if we have a 'non-null' handle here then we are coming + * from the slow path and handle has already been allocated. + */ + if (!handle) + handle = zs_malloc(meta->mem_pool, clen, + __GFP_KSWAPD_RECLAIM | + __GFP_NOWARN | + __GFP_HIGHMEM); if (!handle) { + zcomp_strm_release(zram->comp, zstrm); + zstrm = NULL; + + handle = zs_malloc(meta->mem_pool, clen, + GFP_NOIO | __GFP_HIGHMEM); + if (handle) + goto compress_again; + pr_err("Error allocating memory for compressed page: %u, size=%zu\n", index, clen); ret = -ENOMEM; @@ -1038,7 +1064,7 @@ static ssize_t disksize_store(struct device *dev, if (!meta) return -ENOMEM; - comp = zcomp_create(zram->compressor, zram->max_comp_streams); + comp = zcomp_create(zram->compressor); if (IS_ERR(comp)) { pr_err("Cannot initialise %s compressing backend\n", zram->compressor); |