nvme_alloc_host_mem currently contains two loops that are interwinded,
and the outer retry loop turns out to be broken. Fix this by untangling
the two.
Based on a report an initial patch from Akinobu Mita.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reported-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Tested-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/nvme/host/pci.c | 48 ++++++++++++++++++++++++++++++------------------
1 file changed, 30 insertions(+), 18 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 11874afb2422..e3252bcbc58e 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1616,17 +1616,15 @@ static void nvme_free_host_mem(struct nvme_dev *dev)
dev->host_mem_descs = NULL;
}
-static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
+static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
+ u32 chunk_size)
{
struct nvme_host_mem_buf_desc *descs;
- u32 chunk_size, max_entries, len;
+ u32 max_entries, len;
int i = 0;
void **bufs;
u64 size = 0, tmp;
- /* start big and work our way down */
- chunk_size = min(preferred, (u64)PAGE_SIZE << MAX_ORDER);
-retry:
tmp = (preferred + chunk_size - 1);
do_div(tmp, chunk_size);
max_entries = tmp;
@@ -1652,15 +1650,9 @@ static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
i++;
}
- if (!size || (min && size < min)) {
- dev_warn(dev->ctrl.device,
- "failed to allocate host memory buffer.\n");
+ if (!size)
goto out_free_bufs;
- }
- dev_info(dev->ctrl.device,
- "allocated %lld MiB host memory buffer.\n",
- size >> ilog2(SZ_1M));
dev->nr_host_mem_descs = i;
dev->host_mem_size = size;
dev->host_mem_descs = descs;
@@ -1679,15 +1671,28 @@ static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
out_free_descs:
kfree(descs);
out:
- /* try a smaller chunk size if we failed early */
- if (chunk_size >= PAGE_SIZE * 2 && (i == 0 || size < min)) {
- chunk_size /= 2;
- goto retry;
- }
dev->host_mem_descs = NULL;
return -ENOMEM;
}
+static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
+{
+ u32 chunk_size;
+
+ /* start big and work our way down */
+ for (chunk_size = min_t(u64, preferred, PAGE_SIZE << MAX_ORDER);
+ chunk_size >= PAGE_SIZE * 2;
+ chunk_size /= 2) {
+ if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
+ if (!min || dev->host_mem_size >= min)
+ return 0;
+ nvme_free_host_mem(dev);
+ }
+ }
+
+ return -ENOMEM;
+}
+
static void nvme_setup_host_mem(struct nvme_dev *dev)
{
u64 max = (u64)max_host_mem_size_mb * SZ_1M;
@@ -1715,8 +1720,15 @@ static void nvme_setup_host_mem(struct nvme_dev *dev)
}
if (!dev->host_mem_descs) {
- if (nvme_alloc_host_mem(dev, min, preferred))
+ if (nvme_alloc_host_mem(dev, min, preferred)) {
+ dev_warn(dev->ctrl.device,
+ "failed to allocate host memory buffer.\n");
return;
+ }
+
+ dev_info(dev->ctrl.device,
+ "allocated %lld MiB host memory buffer.\n",
+ dev->host_mem_size >> ilog2(SZ_1M));
}
if (nvme_set_host_mem(dev, enable_bits))
--
2.11.0