engines/libblkio: Allow setting option mem/iomem

[fio.git] / engines / libblkio.c

diff --git a/engines/libblkio.c b/engines/libblkio.c
index 7a5d4271808eed0ad2c9b9178ca2f36abc6b614f..11f45e2a59f17d4382b977d714d284a86d0c4d63 100644 (file)
--- a/engines/libblkio.c
+++ b/engines/libblkio.c
@@ -26,7 +26,7 @@ struct fio_blkio_data {
        struct blkioq *q;
 
        bool has_mem_region; /* whether mem_region is valid */
-       struct blkio_mem_region mem_region;
+       struct blkio_mem_region mem_region; /* only if allocated by libblkio */
 
        struct blkio_completion *completions;
 };
@@ -271,6 +271,47 @@ err_free:
        return 1;
 }
 
+static int fio_blkio_post_init(struct thread_data *td)
+{
+       struct fio_blkio_data *data = td->io_ops_data;
+
+       if (!data->has_mem_region) {
+               /*
+                * Memory was allocated by the fio core and not iomem_alloc(),
+                * so we need to register it as a memory region here.
+                *
+                * `td->orig_buffer_size` is computed like `len` below, but then
+                * fio can add some padding to it to make sure it is
+                * sufficiently aligned to the page size and the mem_align
+                * option. However, this can make it become unaligned to the
+                * "mem-region-alignment" property in ways that the user can't
+                * control, so we essentially recompute `td->orig_buffer_size`
+                * here but without adding that padding.
+                */
+
+               unsigned long long max_block_size;
+               struct blkio_mem_region region;
+
+               max_block_size = max(td->o.max_bs[DDIR_READ],
+                                    max(td->o.max_bs[DDIR_WRITE],
+                                        td->o.max_bs[DDIR_TRIM]));
+
+               region = (struct blkio_mem_region) {
+                       .addr   = td->orig_buffer,
+                       .len    = (size_t)max_block_size *
+                                       (size_t)td->o.iodepth,
+                       .fd     = -1,
+               };
+
+               if (blkio_map_mem_region(data->b, &region) != 0) {
+                       fio_blkio_log_err(blkio_map_mem_region);
+                       return 1;
+               }
+       }
+
+       return 0;
+}
+
 static void fio_blkio_cleanup(struct thread_data *td)
 {
        struct fio_blkio_data *data = td->io_ops_data;
@@ -403,10 +444,11 @@ FIO_STATIC struct ioengine_ops ioengine = {
        .name                   = "libblkio",
        .version                = FIO_IOOPS_VERSION,
        .flags                  = FIO_DISKLESSIO | FIO_NOEXTEND |
-                                 FIO_NO_OFFLOAD,
+                                 FIO_NO_OFFLOAD | FIO_SKIPPABLE_IOMEM_ALLOC,
 
        .setup                  = fio_blkio_setup,
        .init                   = fio_blkio_init,
+       .post_init              = fio_blkio_post_init,
        .cleanup                = fio_blkio_cleanup,
 
        .iomem_alloc            = fio_blkio_iomem_alloc,