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authorRalph Campbell <rcampbell@nvidia.com>2019-05-06 16:29:39 -0700
committerJason Gunthorpe <jgg@mellanox.com>2019-06-06 16:31:40 -0300
commit085ea25064a9169eba5f2ed6484c111ab0f3ee79 (patch)
tree61544b61dea76b4b3379cc7c0203aa07bfbc108e /mm/hmm.c
parent2076e5c0451ca943ff8ecc6def7239c84c77e070 (diff)
mm/hmm: clean up some coding style and comments
There are no functional changes, just some coding style clean ups and minor comment changes. Cc: John Hubbard <jhubbard@nvidia.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Reviewed-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'mm/hmm.c')
-rw-r--r--mm/hmm.c62
1 files changed, 32 insertions, 30 deletions
diff --git a/mm/hmm.c b/mm/hmm.c
index c62ae414a3a2..4db5dcf110ba 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -153,9 +153,8 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm)
/* Wake-up everyone waiting on any range. */
mutex_lock(&hmm->lock);
- list_for_each_entry(range, &hmm->ranges, list) {
+ list_for_each_entry(range, &hmm->ranges, list)
range->valid = false;
- }
wake_up_all(&hmm->wq);
mutex_unlock(&hmm->lock);
@@ -166,9 +165,10 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm)
list_del_init(&mirror->list);
if (mirror->ops->release) {
/*
- * Drop mirrors_sem so callback can wait on any pending
- * work that might itself trigger mmu_notifier callback
- * and thus would deadlock with us.
+ * Drop mirrors_sem so the release callback can wait
+ * on any pending work that might itself trigger a
+ * mmu_notifier callback and thus would deadlock with
+ * us.
*/
up_write(&hmm->mirrors_sem);
mirror->ops->release(mirror);
@@ -223,11 +223,8 @@ static int hmm_invalidate_range_start(struct mmu_notifier *mn,
int ret;
ret = mirror->ops->sync_cpu_device_pagetables(mirror, &update);
- if (!update.blockable && ret == -EAGAIN) {
- up_read(&hmm->mirrors_sem);
- ret = -EAGAIN;
- goto out;
- }
+ if (!update.blockable && ret == -EAGAIN)
+ break;
}
up_read(&hmm->mirrors_sem);
@@ -271,6 +268,7 @@ static const struct mmu_notifier_ops hmm_mmu_notifier_ops = {
*
* @mirror: new mirror struct to register
* @mm: mm to register against
+ * Return: 0 on success, -ENOMEM if no memory, -EINVAL if invalid arguments
*
* To start mirroring a process address space, the device driver must register
* an HMM mirror struct.
@@ -298,7 +296,7 @@ EXPORT_SYMBOL(hmm_mirror_register);
/*
* hmm_mirror_unregister() - unregister a mirror
*
- * @mirror: new mirror struct to register
+ * @mirror: mirror struct to unregister
*
* Stop mirroring a process address space, and cleanup.
*/
@@ -372,7 +370,7 @@ static int hmm_pfns_bad(unsigned long addr,
* @fault: should we fault or not ?
* @write_fault: write fault ?
* @walk: mm_walk structure
- * Returns: 0 on success, -EBUSY after page fault, or page fault error
+ * Return: 0 on success, -EBUSY after page fault, or page fault error
*
* This function will be called whenever pmd_none() or pte_none() returns true,
* or whenever there is no page directory covering the virtual address range.
@@ -911,6 +909,7 @@ int hmm_range_register(struct hmm_range *range,
unsigned page_shift)
{
unsigned long mask = ((1UL << page_shift) - 1UL);
+ struct hmm *hmm;
range->valid = false;
range->hmm = NULL;
@@ -924,28 +923,29 @@ int hmm_range_register(struct hmm_range *range,
range->start = start;
range->end = end;
- range->hmm = hmm_get_or_create(mm);
- if (!range->hmm)
+ hmm = hmm_get_or_create(mm);
+ if (!hmm)
return -EFAULT;
/* Check if hmm_mm_destroy() was call. */
- if (range->hmm->mm == NULL || range->hmm->dead) {
- hmm_put(range->hmm);
+ if (hmm->mm == NULL || hmm->dead) {
+ hmm_put(hmm);
return -EFAULT;
}
- /* Initialize range to track CPU page table update */
- mutex_lock(&range->hmm->lock);
+ /* Initialize range to track CPU page table updates. */
+ mutex_lock(&hmm->lock);
- list_add_rcu(&range->list, &range->hmm->ranges);
+ range->hmm = hmm;
+ list_add_rcu(&range->list, &hmm->ranges);
/*
* If there are any concurrent notifiers we have to wait for them for
* the range to be valid (see hmm_range_wait_until_valid()).
*/
- if (!range->hmm->notifiers)
+ if (!hmm->notifiers)
range->valid = true;
- mutex_unlock(&range->hmm->lock);
+ mutex_unlock(&hmm->lock);
return 0;
}
@@ -960,17 +960,19 @@ EXPORT_SYMBOL(hmm_range_register);
*/
void hmm_range_unregister(struct hmm_range *range)
{
+ struct hmm *hmm = range->hmm;
+
/* Sanity check this really should not happen. */
- if (range->hmm == NULL || range->end <= range->start)
+ if (hmm == NULL || range->end <= range->start)
return;
- mutex_lock(&range->hmm->lock);
+ mutex_lock(&hmm->lock);
list_del_rcu(&range->list);
- mutex_unlock(&range->hmm->lock);
+ mutex_unlock(&hmm->lock);
/* Drop reference taken by hmm_range_register() */
range->valid = false;
- hmm_put(range->hmm);
+ hmm_put(hmm);
range->hmm = NULL;
}
EXPORT_SYMBOL(hmm_range_unregister);
@@ -978,7 +980,7 @@ EXPORT_SYMBOL(hmm_range_unregister);
/*
* hmm_range_snapshot() - snapshot CPU page table for a range
* @range: range
- * Returns: -EINVAL if invalid argument, -ENOMEM out of memory, -EPERM invalid
+ * Return: -EINVAL if invalid argument, -ENOMEM out of memory, -EPERM invalid
* permission (for instance asking for write and range is read only),
* -EAGAIN if you need to retry, -EFAULT invalid (ie either no valid
* vma or it is illegal to access that range), number of valid pages
@@ -1061,7 +1063,7 @@ EXPORT_SYMBOL(hmm_range_snapshot);
* hmm_range_fault() - try to fault some address in a virtual address range
* @range: range being faulted
* @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem)
- * Returns: number of valid pages in range->pfns[] (from range start
+ * Return: number of valid pages in range->pfns[] (from range start
* address). This may be zero. If the return value is negative,
* then one of the following values may be returned:
*
@@ -1179,7 +1181,7 @@ EXPORT_SYMBOL(hmm_range_fault);
* @device: device against to dma map page to
* @daddrs: dma address of mapped pages
* @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem)
- * Returns: number of pages mapped on success, -EAGAIN if mmap_sem have been
+ * Return: number of pages mapped on success, -EAGAIN if mmap_sem have been
* drop and you need to try again, some other error value otherwise
*
* Note same usage pattern as hmm_range_fault().
@@ -1267,7 +1269,7 @@ EXPORT_SYMBOL(hmm_range_dma_map);
* @device: device against which dma map was done
* @daddrs: dma address of mapped pages
* @dirty: dirty page if it had the write flag set
- * Returns: number of page unmapped on success, -EINVAL otherwise
+ * Return: number of page unmapped on success, -EINVAL otherwise
*
* Note that caller MUST abide by mmu notifier or use HMM mirror and abide
* to the sync_cpu_device_pagetables() callback so that it is safe here to
@@ -1390,7 +1392,7 @@ static void hmm_devmem_free(struct page *page, void *data)
* @ops: memory event device driver callback (see struct hmm_devmem_ops)
* @device: device struct to bind the resource too
* @size: size in bytes of the device memory to add
- * Returns: pointer to new hmm_devmem struct ERR_PTR otherwise
+ * Return: pointer to new hmm_devmem struct ERR_PTR otherwise
*
* This function first finds an empty range of physical address big enough to
* contain the new resource, and then hotplugs it as ZONE_DEVICE memory, which