diff mbox

[v4,6/7] blkdebug: Add ability to override unmap geometries

Message ID 20161220191523.5779-7-eblake@redhat.com
State New
Headers show

Commit Message

Eric Blake Dec. 20, 2016, 7:15 p.m. UTC
Make it easier to simulate various unusual hardware setups (for
example, recent commits 3482b9b and b8d0a98 affect the Dell
Equallogic iSCSI with its 15M preferred and maximum unmap and
write zero sizing, or b2f95fe deals with the Linux loopback
block device having a max_transfer of 64k), by allowing blkdebug
to wrap any other device with further restrictions on various
alignments.

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v4: relax 512 byte minimum now that blkdebug is byte-based, fix doc typo
v3: improve legibility of bounds checking, improve docs
v2: new patch
---
 qapi/block-core.json | 24 +++++++++++++-
 block/blkdebug.c     | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 113 insertions(+), 2 deletions(-)

Comments

Max Reitz Jan. 28, 2017, 8:57 p.m. UTC | #1
On 20.12.2016 20:15, Eric Blake wrote:
> Make it easier to simulate various unusual hardware setups (for
> example, recent commits 3482b9b and b8d0a98 affect the Dell
> Equallogic iSCSI with its 15M preferred and maximum unmap and
> write zero sizing, or b2f95fe deals with the Linux loopback
> block device having a max_transfer of 64k), by allowing blkdebug
> to wrap any other device with further restrictions on various
> alignments.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>
> 
> ---
> v4: relax 512 byte minimum now that blkdebug is byte-based, fix doc typo
> v3: improve legibility of bounds checking, improve docs
> v2: new patch
> ---
>  qapi/block-core.json | 24 +++++++++++++-
>  block/blkdebug.c     | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 113 insertions(+), 2 deletions(-)
> 
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 6b42216..6561409 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -2072,6 +2072,26 @@
>  # @align:           #optional required alignment for requests in bytes,
>  #                   must be power of 2, or 0 for default
>  #
> +# @max-transfer:    #optional maximum size for I/O transfers in bytes,
> +#                   must be multiple of @align

...and the file's request alignment. Should that be noted here?

Max

>                                                 (but need not be a power of
> +#                   2), or 0 for default (since 2.9)
> +#
> +# @opt-write-zero:  #optional preferred alignment for write zero requests
> +#                   in bytes, must be multiple of @align (but need not be
> +#                   a power of 2), or 0 for default (since 2.9)
> +#
> +# @max-write-zero:  #optional maximum size for write zero requests in bytes,
> +#                   must be multiple of @align (but need not be a power of
> +#                   2), or 0 for default (since 2.9)
> +#
> +# @opt-discard:     #optional preferred alignment for discard requests
> +#                   in bytes, must be multiple of @align (but need not be
> +#                   a power of 2), or 0 for default (since 2.9)
> +#
> +# @max-discard:     #optional maximum size for discard requests in bytes,
> +#                   must be multiple of @align (but need not be a power of
> +#                   2), or 0 for default (since 2.9)
> +#
>  # @inject-error:    #optional array of error injection descriptions
>  #
>  # @set-state:       #optional array of state-change descriptions
Eric Blake Jan. 30, 2017, 4:54 p.m. UTC | #2
On 01/28/2017 02:57 PM, Max Reitz wrote:
> On 20.12.2016 20:15, Eric Blake wrote:
>> Make it easier to simulate various unusual hardware setups (for
>> example, recent commits 3482b9b and b8d0a98 affect the Dell
>> Equallogic iSCSI with its 15M preferred and maximum unmap and
>> write zero sizing, or b2f95fe deals with the Linux loopback
>> block device having a max_transfer of 64k), by allowing blkdebug
>> to wrap any other device with further restrictions on various
>> alignments.
>>
>> Signed-off-by: Eric Blake <eblake@redhat.com>
>>

>> +++ b/qapi/block-core.json
>> @@ -2072,6 +2072,26 @@
>>  # @align:           #optional required alignment for requests in bytes,
>>  #                   must be power of 2, or 0 for default
>>  #
>> +# @max-transfer:    #optional maximum size for I/O transfers in bytes,
>> +#                   must be multiple of @align
> 
> ...and the file's request alignment. Should that be noted here?

As in - if we set @align to 1, but the underlying file still requires an
alignment of 512, then @max-transfer has to be at least 512.  Yeah, that
makes sense to document.
diff mbox

Patch

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 6b42216..6561409 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2072,6 +2072,26 @@ 
 # @align:           #optional required alignment for requests in bytes,
 #                   must be power of 2, or 0 for default
 #
+# @max-transfer:    #optional maximum size for I/O transfers in bytes,
+#                   must be multiple of @align (but need not be a power of
+#                   2), or 0 for default (since 2.9)
+#
+# @opt-write-zero:  #optional preferred alignment for write zero requests
+#                   in bytes, must be multiple of @align (but need not be
+#                   a power of 2), or 0 for default (since 2.9)
+#
+# @max-write-zero:  #optional maximum size for write zero requests in bytes,
+#                   must be multiple of @align (but need not be a power of
+#                   2), or 0 for default (since 2.9)
+#
+# @opt-discard:     #optional preferred alignment for discard requests
+#                   in bytes, must be multiple of @align (but need not be
+#                   a power of 2), or 0 for default (since 2.9)
+#
+# @max-discard:     #optional maximum size for discard requests in bytes,
+#                   must be multiple of @align (but need not be a power of
+#                   2), or 0 for default (since 2.9)
+#
 # @inject-error:    #optional array of error injection descriptions
 #
 # @set-state:       #optional array of state-change descriptions
@@ -2081,7 +2101,9 @@ 
 { 'struct': 'BlockdevOptionsBlkdebug',
   'data': { 'image': 'BlockdevRef',
             '*config': 'str',
-            '*align': 'int',
+            '*align': 'int', '*max-transfer': 'int32',
+            '*opt-write-zero': 'int32', '*max-write-zero': 'int32',
+            '*opt-discard': 'int32', '*max-discard': 'int32',
             '*inject-error': ['BlkdebugInjectErrorOptions'],
             '*set-state': ['BlkdebugSetStateOptions'] } }

diff --git a/block/blkdebug.c b/block/blkdebug.c
index df68d0f..6f9db15 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -39,6 +39,11 @@  typedef struct BDRVBlkdebugState {
     int state;
     int new_state;
     uint64_t align;
+    uint64_t max_transfer;
+    uint64_t opt_write_zero;
+    uint64_t max_write_zero;
+    uint64_t opt_discard;
+    uint64_t max_discard;

     /* For blkdebug_refresh_filename() */
     char *config_file;
@@ -343,6 +348,31 @@  static QemuOptsList runtime_opts = {
             .type = QEMU_OPT_SIZE,
             .help = "Required alignment in bytes",
         },
+        {
+            .name = "max-transfer",
+            .type = QEMU_OPT_SIZE,
+            .help = "Maximum transfer size in bytes",
+        },
+        {
+            .name = "opt-write-zero",
+            .type = QEMU_OPT_SIZE,
+            .help = "Optimum write zero alignment in bytes",
+        },
+        {
+            .name = "max-write-zero",
+            .type = QEMU_OPT_SIZE,
+            .help = "Maximum write zero size in bytes",
+        },
+        {
+            .name = "opt-discard",
+            .type = QEMU_OPT_SIZE,
+            .help = "Optimum discard alignment in bytes",
+        },
+        {
+            .name = "max-discard",
+            .type = QEMU_OPT_SIZE,
+            .help = "Maximum discard size in bytes",
+        },
         { /* end of list */ }
     },
 };
@@ -354,6 +384,7 @@  static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
     QemuOpts *opts;
     Error *local_err = NULL;
     int ret;
+    uint64_t align;

     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
     qemu_opts_absorb_qdict(opts, options, &local_err);
@@ -387,12 +418,55 @@  static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
     bs->supported_zero_flags = (BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP) &
         bs->file->bs->supported_zero_flags;

-    /* Set request alignment */
+    /* Set alignment overrides */
     s->align = qemu_opt_get_size(opts, "align", 0);
     if (s->align && (s->align >= INT_MAX || !is_power_of_2(s->align))) {
         error_setg(errp, "Invalid alignment, align must be integer power of 2");
         goto fail_unref;
     }
+    align = MAX(s->align, bs->file->bs->bl.request_alignment);
+
+    s->max_transfer = qemu_opt_get_size(opts, "max-transfer", 0);
+    if (s->max_transfer &&
+        (s->max_transfer >= INT_MAX ||
+         !QEMU_IS_ALIGNED(s->max_transfer, align))) {
+        error_setg(errp, "Invalid max-transfer, must be multiple of align");
+        goto fail_unref;
+    }
+
+    s->opt_write_zero = qemu_opt_get_size(opts, "opt-write-zero", 0);
+    if (s->opt_write_zero &&
+        (s->opt_write_zero >= INT_MAX ||
+         !QEMU_IS_ALIGNED(s->opt_write_zero, align))) {
+        error_setg(errp, "Invalid opt-write-zero, not consistent with align");
+        goto fail_unref;
+    }
+
+    s->max_write_zero = qemu_opt_get_size(opts, "max-write-zero", 0);
+    if (s->max_write_zero &&
+        (s->max_write_zero >= INT_MAX ||
+         !QEMU_IS_ALIGNED(s->max_write_zero,
+                          MAX(s->opt_write_zero, align)))) {
+        error_setg(errp, "Invalid max-write-zero, not consistent with align");
+        goto fail_unref;
+    }
+
+    s->opt_discard = qemu_opt_get_size(opts, "opt-discard", 0);
+    if (s->opt_discard &&
+        (s->opt_discard >= INT_MAX ||
+         !QEMU_IS_ALIGNED(s->opt_discard, align))) {
+        error_setg(errp, "Invalid opt-discard, not consistent with align");
+        goto fail_unref;
+    }
+
+    s->max_discard = qemu_opt_get_size(opts, "max-discard", 0);
+    if (s->max_discard &&
+        (s->max_discard >= INT_MAX ||
+         !QEMU_IS_ALIGNED(s->max_discard,
+                          MAX(s->opt_discard, align)))) {
+        error_setg(errp, "Invalid max-discard, not consistent with align");
+        goto fail_unref;
+    }

     ret = 0;
     goto out;
@@ -819,6 +893,21 @@  static void blkdebug_refresh_limits(BlockDriverState *bs, Error **errp)
     if (s->align) {
         bs->bl.request_alignment = s->align;
     }
+    if (s->max_transfer) {
+        bs->bl.max_transfer = s->max_transfer;
+    }
+    if (s->opt_write_zero) {
+        bs->bl.pwrite_zeroes_alignment = s->opt_write_zero;
+    }
+    if (s->max_write_zero) {
+        bs->bl.max_pwrite_zeroes = s->max_write_zero;
+    }
+    if (s->opt_discard) {
+        bs->bl.pdiscard_alignment = s->opt_discard;
+    }
+    if (s->max_discard) {
+        bs->bl.max_pdiscard = s->max_discard;
+    }
 }

 static int blkdebug_reopen_prepare(BDRVReopenState *reopen_state,