diff options
| author | Christoph Hellwig <hch@lst.de> | 2017-09-11 12:08:43 -0400 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2017-09-11 12:29:37 -0400 |
| commit | 92dc689563170b90ba844b8a2eb95e8a5eda2e83 (patch) | |
| tree | 210fe88f087cd10c506106202afc3779cf685d8b | |
| parent | 608cc4b14aeadcf3e4dc325fc211b7052e74b50c (diff) | |
| download | linux-92dc689563170b90ba844b8a2eb95e8a5eda2e83.tar.bz2 | |
nvme-pci: fix host memory buffer allocation fallback
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@lst.de>
Reported-by: Akinobu Mita <akinobu.mita@gmail.com>
Tested-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Cc: stable@vger.kernel.org
| -rw-r--r-- | drivers/nvme/host/pci.c | 48 |
1 files changed, 30 insertions, 18 deletions
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 6ba955ceaec8..82e23c867e42 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1612,18 +1612,16 @@ 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; dma_addr_t descs_dma; 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; @@ -1650,15 +1648,9 @@ retry: 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 @@ out_free_descs: dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs, descs_dma); 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)) |