diff options
| -rw-r--r-- | module/zfs/zio.c | 89 |
1 files changed, 50 insertions, 39 deletions
diff --git a/module/zfs/zio.c b/module/zfs/zio.c index a719e5492..3b3b40fa7 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -158,22 +158,23 @@ zio_init(void) zio_link_cache = kmem_cache_create("zio_link_cache", sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0); + /* + * For small buffers, we want a cache for each multiple of + * SPA_MINBLOCKSIZE. For larger buffers, we want a cache + * for each quarter-power of 2. + */ for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) { size_t size = (c + 1) << SPA_MINBLOCKSHIFT; - size_t align, cflags, data_cflags; - char name[32]; - - /* - * Create cache for each half-power of 2 size, starting from - * SPA_MINBLOCKSIZE. It should give us memory space efficiency - * of ~7/8, sufficient for transient allocations mostly using - * these caches. - */ size_t p2 = size; + size_t align = 0; + size_t data_cflags, cflags; + + data_cflags = KMC_NODEBUG; + cflags = (zio_exclude_metadata || size > zio_buf_debug_limit) ? + KMC_NODEBUG : 0; + while (!ISP2(p2)) p2 &= p2 - 1; - if (!IS_P2ALIGNED(size, p2 / 2)) - continue; #ifndef _KERNEL /* @@ -184,37 +185,47 @@ zio_init(void) */ if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE)) continue; -#endif - - if (IS_P2ALIGNED(size, PAGESIZE)) + /* + * Here's the problem - on 4K native devices in userland on + * Linux using O_DIRECT, buffers must be 4K aligned or I/O + * will fail with EINVAL, causing zdb (and others) to coredump. + * Since userland probably doesn't need optimized buffer caches, + * we just force 4K alignment on everything. + */ + align = 8 * SPA_MINBLOCKSIZE; +#else + if (size < PAGESIZE) { + align = SPA_MINBLOCKSIZE; + } else if (IS_P2ALIGNED(size, p2 >> 2)) { align = PAGESIZE; - else - align = 1 << (highbit64(size ^ (size - 1)) - 1); + } +#endif - cflags = (zio_exclude_metadata || size > zio_buf_debug_limit) ? - KMC_NODEBUG : 0; - data_cflags = KMC_NODEBUG; - if (cflags == data_cflags) { - /* - * Resulting kmem caches would be identical. - * Save memory by creating only one. - */ - (void) snprintf(name, sizeof (name), - "zio_buf_comb_%lu", (ulong_t)size); - zio_buf_cache[c] = kmem_cache_create(name, size, align, - NULL, NULL, NULL, NULL, NULL, cflags); - zio_data_buf_cache[c] = zio_buf_cache[c]; - continue; + if (align != 0) { + char name[36]; + if (cflags == data_cflags) { + /* + * Resulting kmem caches would be identical. + * Save memory by creating only one. + */ + (void) snprintf(name, sizeof (name), + "zio_buf_comb_%lu", (ulong_t)size); + zio_buf_cache[c] = kmem_cache_create(name, + size, align, NULL, NULL, NULL, NULL, NULL, + cflags); + zio_data_buf_cache[c] = zio_buf_cache[c]; + continue; + } + (void) snprintf(name, sizeof (name), "zio_buf_%lu", + (ulong_t)size); + zio_buf_cache[c] = kmem_cache_create(name, size, + align, NULL, NULL, NULL, NULL, NULL, cflags); + + (void) snprintf(name, sizeof (name), "zio_data_buf_%lu", + (ulong_t)size); + zio_data_buf_cache[c] = kmem_cache_create(name, size, + align, NULL, NULL, NULL, NULL, NULL, data_cflags); } - (void) snprintf(name, sizeof (name), "zio_buf_%lu", - (ulong_t)size); - zio_buf_cache[c] = kmem_cache_create(name, size, align, - NULL, NULL, NULL, NULL, NULL, cflags); - - (void) snprintf(name, sizeof (name), "zio_data_buf_%lu", - (ulong_t)size); - zio_data_buf_cache[c] = kmem_cache_create(name, size, align, - NULL, NULL, NULL, NULL, NULL, data_cflags); } while (--c != 0) { |