[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 2/2] block/iscsi: handle failure on malloc of th
From: |
Paolo Bonzini |
Subject: |
Re: [Qemu-devel] [PATCH 2/2] block/iscsi: handle failure on malloc of the allocationmap |
Date: |
Mon, 25 Aug 2014 13:20:37 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 |
Il 25/08/2014 13:10, Peter Lieven ha scritto:
> On 25.08.2014 12:37, Paolo Bonzini wrote:
>> Il 22/08/2014 11:26, Peter Lieven ha scritto:
>>> Signed-off-by: Peter Lieven <address@hidden>
>>> ---
>>> block/iscsi.c | 22 +++++++++++++++-------
>>> 1 file changed, 15 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/block/iscsi.c b/block/iscsi.c
>>> index ed883c3..131357c 100644
>>> --- a/block/iscsi.c
>>> +++ b/block/iscsi.c
>>> @@ -325,6 +325,19 @@ static bool is_request_lun_aligned(int64_t
>>> sector_num, int nb_sectors,
>>> return 1;
>>> }
>>> +static unsigned long *iscsi_allocationmap_init(IscsiLun *iscsilun)
>>> +{
>>> + unsigned long *ptr;
>>> + ptr =
>>> bitmap_try_new(DIV_ROUND_UP(sector_lun2qemu(iscsilun->num_blocks,
>>> + iscsilun),
>>> + iscsilun->cluster_sectors));
>>> + if (ptr == NULL) {
>>> + error_report("iSCSI: could not initialize allocationmap. "
>>> + "Out of memory.");
>>> + }
>>> + return ptr;
>>> +}
>>> +
>>> static void iscsi_allocationmap_set(IscsiLun *iscsilun, int64_t
>>> sector_num,
>>> int nb_sectors)
>>> {
>>> @@ -1413,9 +1426,7 @@ static int iscsi_open(BlockDriverState *bs,
>>> QDict *options, int flags,
>>> iscsilun->cluster_sectors = (iscsilun->bl.opt_unmap_gran *
>>> iscsilun->block_size) >>
>>> BDRV_SECTOR_BITS;
>>> if (iscsilun->lbprz && !(bs->open_flags & BDRV_O_NOCACHE)) {
>>> - iscsilun->allocationmap =
>>> - bitmap_new(DIV_ROUND_UP(bs->total_sectors,
>>> - iscsilun->cluster_sectors));
>>> + iscsilun->allocationmap =
>>> iscsi_allocationmap_init(iscsilun);
>>> }
>>> }
>> iscsi_open has an Error ** argument. Please pass it to
>> iscsi_allocationmap_init and use error_setg instead of error_report.
>
> I could pass the Error argument and use error_report only if the pointer
> is null.
No, NULL means "I don't care about errors, or I don't care about precise
error messages and will use the return value to check for errors".
>>> @@ -1508,10 +1519,7 @@ static int iscsi_truncate(BlockDriverState
>>> *bs, int64_t offset)
>>> if (iscsilun->allocationmap != NULL) {
>>> g_free(iscsilun->allocationmap);
>>> - iscsilun->allocationmap =
>>> -
>>> bitmap_new(DIV_ROUND_UP(sector_lun2qemu(iscsilun->num_blocks,
>>> - iscsilun),
>>> - iscsilun->cluster_sectors));
>>> + iscsilun->allocationmap = iscsi_allocationmap_init(iscsilun);
>> Here you may have to use qerror_report_err, though I guess the failure
>> need not be fatal and you can leave the allocationmap set to NULL.
>
> That was the plan. I would also not fail on iscsi_open or would you?
Hmm, good question. If so, the patch is correct with error_report. I
thought a failure in iscsi_open would be less surprising. The question
then is, do we need an option to disable allocationmap queries?
Paolo
[Qemu-devel] [PATCH 1/2] util: introduce bitmap_try_new, Peter Lieven, 2014/08/22