Fix ENOSPC when unlinking multiple files from full pool

When unlinking multiple files from a pool at 100% capacity, it was
possible for ENOSPC to be returned after the first unlink.  e.g.

    rm -f /mnt/fs/test1.0.0 /mnt/fs/test1.1.0 /mnt/fs/test1.2.0
    rm: cannot remove '/mnt/fs/test1.1.0': No space left on device
    rm: cannot remove '/mnt/fs/test1.2.0': No space left on device

After waiting for the pending deferred frees from the first unlink to
be processed the remaining files can then be unlinked.  This is caused
by the quota limit in dsl_dir_tempreserve_impl() being temporarily
decreased to the allocatable pool capacity less any deferred free
space.

This is resolved using the existing mechanism of returning ERESTART
when over quota as long as we know enough space will shortly be
available after processing the pending deferred frees.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <freqlabs@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13172
This commit is contained in:
Brian Behlendorf
2022-03-08 09:16:35 -08:00
committed by Tony Hutter
parent b3b6491ce9
commit 145af480d3
6 changed files with 84 additions and 8 deletions
+1
View File
@@ -158,6 +158,7 @@ int dsl_pool_sync_context(dsl_pool_t *dp);
uint64_t dsl_pool_adjustedsize(dsl_pool_t *dp, zfs_space_check_t slop_policy);
uint64_t dsl_pool_unreserved_space(dsl_pool_t *dp,
zfs_space_check_t slop_policy);
uint64_t dsl_pool_deferred_space(dsl_pool_t *dp);
void dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx);
void dsl_pool_undirty_space(dsl_pool_t *dp, int64_t space, uint64_t txg);
void dsl_free(dsl_pool_t *dp, uint64_t txg, const blkptr_t *bpp);