[PATCH 0/7] Fixes for LightNVM

[PATCH 0/7] Fixes for LightNVM

[Matias Bjørling]

Hi Jens,

A couple of patches during the last week.

Patch 1: Fix from Keith to compile out lightnvm when it is not
         available.
Patch 2-4: Various memory and check fixes from Tao, Sudip and me.
Patch 5: Refactor device detection ids.
Patch 6: Make get_bb_tbl return converted ppa back to media manager.
Patch 7: Missing locks fixes from Tao on module iterations.

Please pick up when convenient.

Keith Busch (1):
  lightnvm: Simplify config when disabled

Matias Bjørling (2):
  lightnvm: refactor and change vendor id for qemu
  lightnvm: unconverted ppa returned in get_bb_tbl

Sudip Mukherjee (1):
  lightnvm: fix ioctl memory leaks

Wenwei Tao (3):
  lightnvm: free memory when gennvm register fails
  lightnvm: do device max sectors boundary check first
  lightnvm: missing nvm_lock acquire

 drivers/lightnvm/core.c      | 94 ++++++++++++++++++++++++++------------------
 drivers/lightnvm/gennvm.c    | 18 +++++----
 drivers/nvme/host/Makefile   |  3 +-
 drivers/nvme/host/lightnvm.c | 28 ++++++-------
 drivers/nvme/host/nvme.h     | 14 +++++++
 include/linux/lightnvm.h     |  2 +-
 6 files changed, 95 insertions(+), 64 deletions(-)

-- 
2.1.4

[PATCH 1/7] lightnvm: Simplify config when disabled

[Matias Bjørling]

From: Keith Busch <keith.busch@intel.com>

We shouldn't compile an object file to get empty implementations;
conforms to linux coding style on conditional compilation.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/nvme/host/Makefile   |  3 ++-
 drivers/nvme/host/lightnvm.c | 13 -------------
 drivers/nvme/host/nvme.h     | 14 ++++++++++++++
 3 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/nvme/host/Makefile b/drivers/nvme/host/Makefile
index 219dc206..a5fe239 100644
--- a/drivers/nvme/host/Makefile
+++ b/drivers/nvme/host/Makefile
@@ -1,4 +1,5 @@
 
 obj-$(CONFIG_BLK_DEV_NVME)     += nvme.o
 
-nvme-y		+= pci.o scsi.o lightnvm.o
+lightnvm-$(CONFIG_NVM)	:= lightnvm.o
+nvme-y		+= pci.o scsi.o $(lightnvm-y)
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 9202d1a..07451d6 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -22,8 +22,6 @@
 
 #include "nvme.h"
 
-#ifdef CONFIG_NVM
-
 #include <linux/nvme.h>
 #include <linux/bitops.h>
 #include <linux/lightnvm.h>
@@ -588,14 +586,3 @@ int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
 
 	return 0;
 }
-#else
-int nvme_nvm_register(struct request_queue *q, char *disk_name)
-{
-	return 0;
-}
-void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
-int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
-{
-	return 0;
-}
-#endif /* CONFIG_NVM */
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index fdb4e5b..044253d 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -136,8 +136,22 @@ int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
 int nvme_sg_get_version_num(int __user *ip);
 
+#ifdef CONFIG_NVM
 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
 int nvme_nvm_register(struct request_queue *q, char *disk_name);
 void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
+#else
+static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
+{
+	return 0;
+}
+
+static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
+
+static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
+{
+	return 0;
+}
+#endif /* CONFIG_NVM */
 
 #endif /* _NVME_H */
-- 
2.1.4

[PATCH 2/7] lightnvm: free memory when gennvm register fails

[Matias Bjørling]

From: Wenwei Tao <ww.tao0320@gmail.com>

free allocated nvm block and gennvm lun structures when
gennvm register fails, otherwise it will cause memory leak.

Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/lightnvm/gennvm.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/lightnvm/gennvm.c b/drivers/lightnvm/gennvm.c
index e20e74e..3969a98 100644
--- a/drivers/lightnvm/gennvm.c
+++ b/drivers/lightnvm/gennvm.c
@@ -207,6 +207,14 @@ static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
 	return 0;
 }
 
+static void gennvm_free(struct nvm_dev *dev)
+{
+	gennvm_blocks_free(dev);
+	gennvm_luns_free(dev);
+	kfree(dev->mp);
+	dev->mp = NULL;
+}
+
 static int gennvm_register(struct nvm_dev *dev)
 {
 	struct gen_nvm *gn;
@@ -234,16 +242,13 @@ static int gennvm_register(struct nvm_dev *dev)
 
 	return 1;
 err:
-	kfree(gn);
+	gennvm_free(dev);
 	return ret;
 }
 
 static void gennvm_unregister(struct nvm_dev *dev)
 {
-	gennvm_blocks_free(dev);
-	gennvm_luns_free(dev);
-	kfree(dev->mp);
-	dev->mp = NULL;
+	gennvm_free(dev);
 }
 
 static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
-- 
2.1.4

[PATCH 3/7] lightnvm: fix ioctl memory leaks

[Matias Bjørling]

From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>

If copy_to_user() fails we returned error but we missed releasing
devices.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/lightnvm/core.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 5178645..ea50fa5 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -680,8 +680,10 @@ static long nvm_ioctl_info(struct file *file, void __user *arg)
 	info->tgtsize = tgt_iter;
 	up_write(&nvm_lock);
 
-	if (copy_to_user(arg, info, sizeof(struct nvm_ioctl_info)))
+	if (copy_to_user(arg, info, sizeof(struct nvm_ioctl_info))) {
+		kfree(info);
 		return -EFAULT;
+	}
 
 	kfree(info);
 	return 0;
@@ -724,8 +726,11 @@ static long nvm_ioctl_get_devices(struct file *file, void __user *arg)
 
 	devices->nr_devices = i;
 
-	if (copy_to_user(arg, devices, sizeof(struct nvm_ioctl_get_devices)))
+	if (copy_to_user(arg, devices,
+			 sizeof(struct nvm_ioctl_get_devices))) {
+		kfree(devices);
 		return -EFAULT;
+	}
 
 	kfree(devices);
 	return 0;
-- 
2.1.4

[PATCH 4/7] lightnvm: do device max sectors boundary check first

[Matias Bjørling]

From: Wenwei Tao <ww.tao0320@gmail.com>

do device max_phys_sect boundary check first, otherwise
we will allocate dma_pools for devices whose max sectors
are beyond lightnvm support and register them.

Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/lightnvm/core.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index ea50fa5..ea6dba5 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -308,6 +308,12 @@ int nvm_register(struct request_queue *q, char *disk_name,
 	if (ret)
 		goto err_init;
 
+	if (dev->ops->max_phys_sect > 256) {
+		pr_info("nvm: max sectors supported is 256.\n");
+		ret = -EINVAL;
+		goto err_init;
+	}
+
 	if (dev->ops->max_phys_sect > 1) {
 		dev->ppalist_pool = dev->ops->create_dma_pool(dev->q,
 								"ppalist");
@@ -316,10 +322,6 @@ int nvm_register(struct request_queue *q, char *disk_name,
 			ret = -ENOMEM;
 			goto err_init;
 		}
-	} else if (dev->ops->max_phys_sect > 256) {
-		pr_info("nvm: max sectors supported is 256.\n");
-		ret = -EINVAL;
-		goto err_init;
 	}
 
 	down_write(&nvm_lock);
-- 
2.1.4

[PATCH 5/7] lightnvm: refactor and change vendor id for qemu

[Matias Bjørling]

The QEMU NVMe implementation uses Intel vendor, Intel device id, and the
first vendor specific byte to identify a LightNVM compatible nvme
instance.

Instead of using the Intel specific, use a preallocated from CNEX Labs
instead. This lets us uniquely identify a QEMU lightnvm device without
breaking other vendor specific work in the qemu device driver.

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/nvme/host/lightnvm.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 07451d6..b9e5cc7 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -569,18 +569,25 @@ void nvme_nvm_unregister(struct request_queue *q, char *disk_name)
 	nvm_unregister(disk_name);
 }
 
+/* move to shared place when used in multiple places. */
+#define PCI_VENDOR_ID_CNEX 0x1d1d
+#define PCI_DEVICE_ID_CNEX_WL 0x2807
+#define PCI_DEVICE_ID_CNEX_QEMU 0x1f1f
+
 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
 {
 	struct nvme_dev *dev = ns->dev;
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
 	/* QEMU NVMe simulator - PCI ID + Vendor specific bit */
-	if (pdev->vendor == PCI_VENDOR_ID_INTEL && pdev->device == 0x5845 &&
+	if (pdev->vendor == PCI_VENDOR_ID_CNEX &&
+				pdev->device == PCI_DEVICE_ID_CNEX_QEMU &&
 							id->vs[0] == 0x1)
 		return 1;
 
 	/* CNEX Labs - PCI ID + Vendor specific bit */
-	if (pdev->vendor == 0x1d1d && pdev->device == 0x2807 &&
+	if (pdev->vendor == PCI_VENDOR_ID_CNEX &&
+				pdev->device == PCI_DEVICE_ID_CNEX_WL &&
 							id->vs[0] == 0x1)
 		return 1;
 
-- 
2.1.4

[PATCH 6/7] lightnvm: unconverted ppa returned in get_bb_tbl

[Matias Bjørling]

The get_bb_tbl function takes ppa as a generic address, which is
converted to the ppa device address within the device driver. When
the update_bbtbl callback is called from get_bb_tbl, the device
specific ppa is used, instead of the generic ppa.

Make sure to pass the generic ppa.

Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/lightnvm/gennvm.c    | 3 +--
 drivers/nvme/host/lightnvm.c | 4 +++-
 include/linux/lightnvm.h     | 2 +-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/lightnvm/gennvm.c b/drivers/lightnvm/gennvm.c
index 3969a98..35dde84 100644
--- a/drivers/lightnvm/gennvm.c
+++ b/drivers/lightnvm/gennvm.c
@@ -75,7 +75,6 @@ static int gennvm_block_bb(struct ppa_addr ppa, int nr_blocks, u8 *blks,
 	struct nvm_block *blk;
 	int i;
 
-	ppa = dev_to_generic_addr(gn->dev, ppa);
 	lun = &gn->luns[(dev->nr_luns * ppa.g.ch) + ppa.g.lun];
 
 	for (i = 0; i < nr_blocks; i++) {
@@ -187,7 +186,7 @@ static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
 			ppa.g.lun = lun->vlun.id;
 			ppa = generic_to_dev_addr(dev, ppa);
 
-			ret = dev->ops->get_bb_tbl(dev->q, ppa,
+			ret = dev->ops->get_bb_tbl(dev, ppa,
 						dev->blks_per_lun,
 						gennvm_block_bb, gn);
 			if (ret)
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index b9e5cc7..06c3364 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -355,10 +355,11 @@ out:
 	return ret;
 }
 
-static int nvme_nvm_get_bb_tbl(struct request_queue *q, struct ppa_addr ppa,
+static int nvme_nvm_get_bb_tbl(struct nvm_dev *nvmdev, struct ppa_addr ppa,
 				int nr_blocks, nvm_bb_update_fn *update_bbtbl,
 				void *priv)
 {
+	struct request_queue *q = nvmdev->q;
 	struct nvme_ns *ns = q->queuedata;
 	struct nvme_dev *dev = ns->dev;
 	struct nvme_nvm_command c = {};
@@ -402,6 +403,7 @@ static int nvme_nvm_get_bb_tbl(struct request_queue *q, struct ppa_addr ppa,
 		goto out;
 	}
 
+	ppa = dev_to_generic_addr(nvmdev, ppa);
 	ret = update_bbtbl(ppa, nr_blocks, bb_tbl->blk, priv);
 	if (ret) {
 		ret = -EINTR;
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index 3db5552..c6916ae 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -179,7 +179,7 @@ typedef int (nvm_bb_update_fn)(struct ppa_addr, int, u8 *, void *);
 typedef int (nvm_id_fn)(struct request_queue *, struct nvm_id *);
 typedef int (nvm_get_l2p_tbl_fn)(struct request_queue *, u64, u32,
 				nvm_l2p_update_fn *, void *);
-typedef int (nvm_op_bb_tbl_fn)(struct request_queue *, struct ppa_addr, int,
+typedef int (nvm_op_bb_tbl_fn)(struct nvm_dev *, struct ppa_addr, int,
 				nvm_bb_update_fn *, void *);
 typedef int (nvm_op_set_bb_fn)(struct request_queue *, struct nvm_rq *, int);
 typedef int (nvm_submit_io_fn)(struct request_queue *, struct nvm_rq *);
-- 
2.1.4

[PATCH 7/7] lightnvm: missing nvm_lock acquire

[Matias Bjørling]

From: Wenwei Tao <ww.tao0320@gmail.com>

To avoid race conditions, traverse dev, media manager,
and target lists and also register, unregister entries
to/from them, should be always under the nvm_lock control.

Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/lightnvm/core.c | 75 +++++++++++++++++++++++++++----------------------
 1 file changed, 42 insertions(+), 33 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index ea6dba5..86ce887 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -123,6 +123,26 @@ void nvm_unregister_mgr(struct nvmm_type *mt)
 }
 EXPORT_SYMBOL(nvm_unregister_mgr);
 
+/* register with device with a supported manager */
+static int register_mgr(struct nvm_dev *dev)
+{
+	struct nvmm_type *mt;
+	int ret = 0;
+
+	list_for_each_entry(mt, &nvm_mgrs, list) {
+		ret = mt->register_mgr(dev);
+		if (ret > 0) {
+			dev->mt = mt;
+			break; /* successfully initialized */
+		}
+	}
+
+	if (!ret)
+		pr_info("nvm: no compatible nvm manager found.\n");
+
+	return ret;
+}
+
 static struct nvm_dev *nvm_find_nvm_dev(const char *name)
 {
 	struct nvm_dev *dev;
@@ -221,7 +241,6 @@ static void nvm_free(struct nvm_dev *dev)
 
 static int nvm_init(struct nvm_dev *dev)
 {
-	struct nvmm_type *mt;
 	int ret = -EINVAL;
 
 	if (!dev->q || !dev->ops)
@@ -252,21 +271,13 @@ static int nvm_init(struct nvm_dev *dev)
 		goto err;
 	}
 
-	/* register with device with a supported manager */
-	list_for_each_entry(mt, &nvm_mgrs, list) {
-		ret = mt->register_mgr(dev);
-		if (ret < 0)
-			goto err; /* initialization failed */
-		if (ret > 0) {
-			dev->mt = mt;
-			break; /* successfully initialized */
-		}
-	}
-
-	if (!ret) {
-		pr_info("nvm: no compatible manager found.\n");
+	down_write(&nvm_lock);
+	ret = register_mgr(dev);
+	up_write(&nvm_lock);
+	if (ret < 0)
+		goto err;
+	if (!ret)
 		return 0;
-	}
 
 	pr_info("nvm: registered %s [%u/%u/%u/%u/%u/%u]\n",
 			dev->name, dev->sec_per_pg, dev->nr_planes,
@@ -337,15 +348,17 @@ EXPORT_SYMBOL(nvm_register);
 
 void nvm_unregister(char *disk_name)
 {
-	struct nvm_dev *dev = nvm_find_nvm_dev(disk_name);
+	struct nvm_dev *dev;
 
+	down_write(&nvm_lock);
+	dev = nvm_find_nvm_dev(disk_name);
 	if (!dev) {
 		pr_err("nvm: could not find device %s to unregister\n",
 								disk_name);
+		up_write(&nvm_lock);
 		return;
 	}
 
-	down_write(&nvm_lock);
 	list_del(&dev->devices);
 	up_write(&nvm_lock);
 
@@ -363,38 +376,30 @@ static int nvm_create_target(struct nvm_dev *dev,
 {
 	struct nvm_ioctl_create_simple *s = &create->conf.s;
 	struct request_queue *tqueue;
-	struct nvmm_type *mt;
 	struct gendisk *tdisk;
 	struct nvm_tgt_type *tt;
 	struct nvm_target *t;
 	void *targetdata;
 	int ret = 0;
 
+	down_write(&nvm_lock);
 	if (!dev->mt) {
-		/* register with device with a supported NVM manager */
-		list_for_each_entry(mt, &nvm_mgrs, list) {
-			ret = mt->register_mgr(dev);
-			if (ret < 0)
-				return ret; /* initialization failed */
-			if (ret > 0) {
-				dev->mt = mt;
-				break; /* successfully initialized */
-			}
-		}
-
-		if (!ret) {
-			pr_info("nvm: no compatible nvm manager found.\n");
-			return -ENODEV;
+		ret = register_mgr(dev);
+		if (!ret)
+			ret = -ENODEV;
+		if (ret < 0) {
+			up_write(&nvm_lock);
+			return ret;
 		}
 	}
 
 	tt = nvm_find_target_type(create->tgttype);
 	if (!tt) {
 		pr_err("nvm: target type %s not found\n", create->tgttype);
+		up_write(&nvm_lock);
 		return -EINVAL;
 	}
 
-	down_write(&nvm_lock);
 	list_for_each_entry(t, &dev->online_targets, list) {
 		if (!strcmp(create->tgtname, t->disk->disk_name)) {
 			pr_err("nvm: target name already exists.\n");
@@ -478,7 +483,9 @@ static int __nvm_configure_create(struct nvm_ioctl_create *create)
 	struct nvm_dev *dev;
 	struct nvm_ioctl_create_simple *s;
 
+	down_write(&nvm_lock);
 	dev = nvm_find_nvm_dev(create->dev);
+	up_write(&nvm_lock);
 	if (!dev) {
 		pr_err("nvm: device not found\n");
 		return -EINVAL;
@@ -537,7 +544,9 @@ static int nvm_configure_show(const char *val)
 		return -EINVAL;
 	}
 
+	down_write(&nvm_lock);
 	dev = nvm_find_nvm_dev(devname);
+	up_write(&nvm_lock);
 	if (!dev) {
 		pr_err("nvm: device not found\n");
 		return -EINVAL;
-- 
2.1.4

Re: [PATCH 0/7] Fixes for LightNVM

[Jens Axboe]

On 11/28/2015 08:49 AM, Matias Bjørling wrote:
> Hi Jens,
>
> A couple of patches during the last week.
>
> Patch 1: Fix from Keith to compile out lightnvm when it is not
>           available.
> Patch 2-4: Various memory and check fixes from Tao, Sudip and me.
> Patch 5: Refactor device detection ids.
> Patch 6: Make get_bb_tbl return converted ppa back to media manager.
> Patch 7: Missing locks fixes from Tao on module iterations.
>
> Please pick up when convenient.

Added, thanks.

-- 
Jens Axboe