The patch titled
Subject: idr: remove _idr_rc_to_errno() hack
has been added to the -mm tree. Its filename is
idr-remove-_idr_rc_to_errno-hack.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Tejun Heo <tj@xxxxxxxxxx>
Subject: idr: remove _idr_rc_to_errno() hack
idr uses -1, IDR_NEED_TO_GROW and IDR_NOMORE_SPACE to communicate
exception conditions internally. The return value is later translated
to errno values using _idr_rc_to_errno().
This is confusing. Drop the custom ones and consistently use -EAGAIN
for "tree needs to grow", -ENOMEM for "need more memory" and -ENOSPC
for "ran out of ID space".
Due to the weird memory preloading mechanism, [ra]_get_new*() return
-EAGAIN on memory shortage, so we need to substitute -ENOMEM w/
-EAGAIN on those interface functions. They'll eventually be cleaned
up and the translations will go away.
This patch doesn't introduce any functional changes.
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/idr.h | 6 ------
lib/idr.c | 35 +++++++++++++++++++++++------------
2 files changed, 23 insertions(+), 18 deletions(-)
diff -puN include/linux/idr.h~idr-remove-_idr_rc_to_errno-hack include/linux/idr.h
--- a/include/linux/idr.h~idr-remove-_idr_rc_to_errno-hack
+++ a/include/linux/idr.h
@@ -70,12 +70,6 @@ struct idr {
}
#define DEFINE_IDR(name) struct idr name = IDR_INIT(name)
-/* Actions to be taken after a call to _idr_sub_alloc */
-#define IDR_NEED_TO_GROW -2
-#define IDR_NOMORE_SPACE -3
-
-#define _idr_rc_to_errno(rc) ((rc) == -1 ? -EAGAIN : -ENOSPC)
-
/**
* DOC: idr sync
* idr synchronization (stolen from radix-tree.h)
diff -puN lib/idr.c~idr-remove-_idr_rc_to_errno-hack lib/idr.c
--- a/lib/idr.c~idr-remove-_idr_rc_to_errno-hack
+++ a/lib/idr.c
@@ -133,6 +133,21 @@ int idr_pre_get(struct idr *idp, gfp_t g
}
EXPORT_SYMBOL(idr_pre_get);
+/**
+ * sub_alloc - try to allocate an id without growing the tree depth
+ * @idp: idr handle
+ * @starting_id: id to start search at
+ * @id: pointer to the allocated handle
+ * @pa: idr_layer[MAX_IDR_LEVEL] used as backtrack buffer
+ *
+ * Allocate an id in range [@starting_id, INT_MAX] from @idp without
+ * growing its depth. Returns
+ *
+ * the allocated id >= 0 if successful,
+ * -EAGAIN if the tree needs to grow for allocation to succeed,
+ * -ENOSPC if the id space is exhausted,
+ * -ENOMEM if more idr_layers need to be allocated.
+ */
static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
{
int n, m, sh;
@@ -161,7 +176,7 @@ static int sub_alloc(struct idr *idp, in
/* if already at the top layer, we need to grow */
if (id >= 1 << (idp->layers * IDR_BITS)) {
*starting_id = id;
- return IDR_NEED_TO_GROW;
+ return -EAGAIN;
}
p = pa[l];
BUG_ON(!p);
@@ -180,7 +195,7 @@ static int sub_alloc(struct idr *idp, in
id = ((id >> sh) ^ n ^ m) << sh;
}
if ((id >= MAX_IDR_BIT) || (id < 0))
- return IDR_NOMORE_SPACE;
+ return -ENOSPC;
if (l == 0)
break;
/*
@@ -189,7 +204,7 @@ static int sub_alloc(struct idr *idp, in
if (!p->ary[m]) {
new = get_from_free_list(idp);
if (!new)
- return -1;
+ return -ENOMEM;
new->layer = l-1;
rcu_assign_pointer(p->ary[m], new);
p->count++;
@@ -215,7 +230,7 @@ build_up:
layers = idp->layers;
if (unlikely(!p)) {
if (!(p = get_from_free_list(idp)))
- return -1;
+ return -ENOMEM;
p->layer = 0;
layers = 1;
}
@@ -246,7 +261,7 @@ build_up:
__move_to_free_list(idp, new);
}
spin_unlock_irqrestore(&idp->lock, flags);
- return -1;
+ return -ENOMEM;
}
new->ary[0] = p;
new->count = 1;
@@ -258,7 +273,7 @@ build_up:
rcu_assign_pointer(idp->top, p);
idp->layers = layers;
v = sub_alloc(idp, &id, pa);
- if (v == IDR_NEED_TO_GROW)
+ if (v == -EAGAIN)
goto build_up;
return(v);
}
@@ -306,12 +321,8 @@ int idr_get_new_above(struct idr *idp, v
int rv;
rv = idr_get_new_above_int(idp, ptr, starting_id);
- /*
- * This is a cheap hack until the IDR code can be fixed to
- * return proper error values.
- */
if (rv < 0)
- return _idr_rc_to_errno(rv);
+ return rv == -ENOMEM ? -EAGAIN : rv;
*id = rv;
return 0;
}
@@ -766,7 +777,7 @@ int ida_get_new_above(struct ida *ida, i
/* get vacant slot */
t = idr_get_empty_slot(&ida->idr, idr_id, pa);
if (t < 0)
- return _idr_rc_to_errno(t);
+ return t == -ENOMEM ? -EAGAIN : t;
if (t * IDA_BITMAP_BITS >= MAX_IDR_BIT)
return -ENOSPC;
_
Patches currently in -mm which might be from tj@xxxxxxxxxx are
linux-next.patch
cfq-fix-lock-imbalance-with-failed-allocations.patch
block-restore-proc-partitions-to-not-display-non-partitionable-removable-devices.patch
memcg-do-not-create-memsw-files-if-swap-accounting-is-disabled.patch
memcg-clean-up-swap-accounting-initialization-code.patch
memcg-prevent-changes-to-move_charge_at_immigrate-during-task-attach.patch
memcg-split-part-of-memcg-creation-to-css_online.patch
memcg-fast-hierarchy-aware-child-test.patch
memcg-fast-hierarchy-aware-child-test-fix.patch
memcg-replace-cgroup_lock-with-memcg-specific-memcg_lock.patch
memcg-increment-static-branch-right-after-limit-set.patch
memcg-avoid-dangling-reference-count-in-creation-failure.patch
idr-fix-a-subtle-bug-in-idr_get_next.patch
idr-make-idr_destroy-imply-idr_remove_all.patch
atm-nicstar-dont-use-idr_remove_all.patch
block-loop-dont-use-idr_remove_all.patch
firewire-dont-use-idr_remove_all.patch
drm-dont-use-idr_remove_all.patch
dm-dont-use-idr_remove_all.patch
remoteproc-dont-use-idr_remove_all.patch
rpmsg-dont-use-idr_remove_all.patch
dlm-use-idr_for_each_entry-in-recover_idr_clear-error-path.patch
dlm-dont-use-idr_remove_all.patch
nfs-idr_destroy-no-longer-needs-idr_remove_all.patch
inotify-dont-use-idr_remove_all.patch
cgroup-dont-use-idr_remove_all.patch
idr-deprecate-idr_remove_all.patch
idr-cosmetic-updates-to-struct-initializer-definitions.patch
idr-relocate-idr_for_each_entry-and-reorganize-id_get_new.patch
idr-remove-_idr_rc_to_errno-hack.patch
idr-refactor-idr_get_new_above.patch
idr-implement-idr_preload-and-idr_alloc.patch
block-fix-synchronization-and-limit-check-in-blk_alloc_devt.patch
block-convert-to-idr_alloc.patch
block-loop-convert-to-idr_alloc.patch
atm-nicstar-convert-to-idr_alloc.patch
drbd-convert-to-idr_alloc.patch
dca-convert-to-idr_alloc.patch
dmaengine-convert-to-idr_alloc.patch
firewire-add-minor-number-range-check-to-fw_device_init.patch
firewire-convert-to-idr_alloc.patch
gpio-convert-to-idr_alloc.patch
drm-convert-to-idr_alloc.patch
drm-exynos-convert-to-idr_alloc.patch
drm-i915-convert-to-idr_alloc.patch
drm-sis-convert-to-idr_alloc.patch
drm-via-convert-to-idr_alloc.patch
drm-vmwgfx-convert-to-idr_alloc.patch
i2c-convert-to-idr_alloc.patch
ib-core-convert-to-idr_alloc.patch
ib-amso1100-convert-to-idr_alloc.patch
ib-cxgb3-convert-to-idr_alloc.patch
ib-cxgb4-convert-to-idr_alloc.patch
ib-ehca-convert-to-idr_alloc.patch
ib-ipath-convert-to-idr_alloc.patch
ib-mlx4-convert-to-idr_alloc.patch
ib-ocrdma-convert-to-idr_alloc.patch
ib-qib-convert-to-idr_alloc.patch
dm-convert-to-idr_alloc.patch
memstick-convert-to-idr_alloc.patch
mfd-convert-to-idr_alloc.patch
misc-c2port-convert-to-idr_alloc.patch
misc-tifm_core-convert-to-idr_alloc.patch
mmc-convert-to-idr_alloc.patch
mtd-convert-to-idr_alloc.patch
macvtap-convert-to-idr_alloc.patch
ppp-convert-to-idr_alloc.patch
power-convert-to-idr_alloc.patch
pps-convert-to-idr_alloc.patch
remoteproc-convert-to-idr_alloc.patch
rpmsg-convert-to-idr_alloc.patch
scsi-bfa-convert-to-idr_alloc.patch
scsi-convert-to-idr_alloc.patch
target-iscsi-convert-to-idr_alloc.patch
scsi-lpfc-convert-to-idr_alloc.patch
thermal-convert-to-idr_alloc.patch
uio-convert-to-idr_alloc.patch
vfio-convert-to-idr_alloc.patch
dlm-convert-to-idr_alloc.patch
inotify-convert-to-idr_alloc.patch
ocfs2-convert-to-idr_alloc.patch
ipc-convert-to-idr_alloc.patch
cgroup-convert-to-idr_alloc.patch
events-convert-to-idr_alloc.patch
posix-timers-convert-to-idr_alloc.patch
net-9p-convert-to-idr_alloc.patch
mac80211-convert-to-idr_alloc.patch
sctp-convert-to-idr_alloc.patch
nfs4client-convert-to-idr_alloc.patch
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