From: Dave Jiang <dave.jiang@intel.com>
To: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
vkoul@kernel.org
Cc: dan.j.williams@intel.com, tony.luck@intel.com,
jing.lin@intel.com, ashok.raj@intel.com,
sanjay.k.kumar@intel.com, megha.dey@intel.com,
jacob.jun.pan@intel.com, yi.l.liu@intel.com, axboe@kernel.dk,
akpm@linux-foundation.org, tglx@linutronix.de, mingo@redhat.com,
bp@alien8.de, fenghua.yu@intel.com, hpa@zytor.com
Subject: [PATCH RFC v2 02/14] dmaengine: break out channel registration
Date: Thu, 12 Dec 2019 11:24:22 -0700 [thread overview]
Message-ID: <157617506217.42350.158281933095533374.stgit@djiang5-desk3.ch.intel.com> (raw)
In-Reply-To: <157617487798.42350.4471714981643413895.stgit@djiang5-desk3.ch.intel.com>
In preparation for dynamic channel registration, the code segment that
does the channel registration is broken out to its own function.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
drivers/dma/dmaengine.c | 157 ++++++++++++++++++++++++++++++---------------
include/linux/dmaengine.h | 4 +
2 files changed, 107 insertions(+), 54 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 03ac4b96117c..a20ab568b637 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -900,15 +900,109 @@ static int get_dma_id(struct dma_device *device)
return 0;
}
+static int __dma_async_device_channel_register(struct dma_device *device,
+ struct dma_chan *chan,
+ int chan_id)
+{
+ int rc = 0;
+ int chancnt = device->chancnt;
+ atomic_t *idr_ref;
+ struct dma_chan *tchan;
+
+ tchan = list_first_entry_or_null(&device->channels,
+ struct dma_chan, device_node);
+ if (tchan->dev) {
+ idr_ref = tchan->dev->idr_ref;
+ } else {
+ idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL);
+ if (!idr_ref)
+ return -ENOMEM;
+ atomic_set(idr_ref, 0);
+ }
+
+ chan->local = alloc_percpu(typeof(*chan->local));
+ if (!chan->local)
+ goto err_out;
+ chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL);
+ if (!chan->dev) {
+ free_percpu(chan->local);
+ chan->local = NULL;
+ goto err_out;
+ }
+
+ /*
+ * When the chan_id is a negative value, we are dynamically adding
+ * the channel. Otherwise we are static enumerating.
+ */
+ chan->chan_id = chan_id < 0 ? chancnt : chan_id;
+ chan->dev->device.class = &dma_devclass;
+ chan->dev->device.parent = device->dev;
+ chan->dev->chan = chan;
+ chan->dev->idr_ref = idr_ref;
+ chan->dev->dev_id = device->dev_id;
+ atomic_inc(idr_ref);
+ dev_set_name(&chan->dev->device, "dma%dchan%d",
+ device->dev_id, chan->chan_id);
+
+ rc = device_register(&chan->dev->device);
+ if (rc)
+ goto err_out;
+ chan->client_count = 0;
+ device->chancnt = chan->chan_id + 1;
+
+ return 0;
+
+ err_out:
+ free_percpu(chan->local);
+ kfree(chan->dev);
+ if (atomic_dec_return(idr_ref) == 0)
+ kfree(idr_ref);
+ return rc;
+}
+
+int dma_async_device_channel_register(struct dma_device *device,
+ struct dma_chan *chan)
+{
+ int rc;
+
+ rc = __dma_async_device_channel_register(device, chan, -1);
+ if (rc < 0)
+ return rc;
+
+ dma_channel_rebalance();
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dma_async_device_channel_register);
+
+static void __dma_async_device_channel_unregister(struct dma_device *device,
+ struct dma_chan *chan)
+{
+ WARN_ONCE(chan->client_count,
+ "%s called while %d clients hold a reference\n",
+ __func__, chan->client_count);
+ mutex_lock(&dma_list_mutex);
+ chan->dev->chan = NULL;
+ mutex_unlock(&dma_list_mutex);
+ device_unregister(&chan->dev->device);
+ free_percpu(chan->local);
+}
+
+void dma_async_device_channel_unregister(struct dma_device *device,
+ struct dma_chan *chan)
+{
+ __dma_async_device_channel_unregister(device, chan);
+ dma_channel_rebalance();
+}
+EXPORT_SYMBOL_GPL(dma_async_device_channel_unregister);
+
/**
* dma_async_device_register - registers DMA devices found
* @device: &dma_device
*/
int dma_async_device_register(struct dma_device *device)
{
- int chancnt = 0, rc;
+ int rc, i = 0;
struct dma_chan* chan;
- atomic_t *idr_ref;
if (!device)
return -ENODEV;
@@ -1000,59 +1094,23 @@ int dma_async_device_register(struct dma_device *device)
if (device_has_all_tx_types(device))
dma_cap_set(DMA_ASYNC_TX, device->cap_mask);
- idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL);
- if (!idr_ref)
- return -ENOMEM;
rc = get_dma_id(device);
- if (rc != 0) {
- kfree(idr_ref);
+ if (rc != 0)
return rc;
- }
-
- atomic_set(idr_ref, 0);
/* represent channels in sysfs. Probably want devs too */
list_for_each_entry(chan, &device->channels, device_node) {
- rc = -ENOMEM;
- chan->local = alloc_percpu(typeof(*chan->local));
- if (chan->local == NULL)
+ rc = __dma_async_device_channel_register(device, chan, i++);
+ if (rc < 0)
goto err_out;
- chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL);
- if (chan->dev == NULL) {
- free_percpu(chan->local);
- chan->local = NULL;
- goto err_out;
- }
-
- chan->chan_id = chancnt++;
- chan->dev->device.class = &dma_devclass;
- chan->dev->device.parent = device->dev;
- chan->dev->chan = chan;
- chan->dev->idr_ref = idr_ref;
- chan->dev->dev_id = device->dev_id;
- atomic_inc(idr_ref);
- dev_set_name(&chan->dev->device, "dma%dchan%d",
- device->dev_id, chan->chan_id);
-
- rc = device_register(&chan->dev->device);
- if (rc) {
- free_percpu(chan->local);
- chan->local = NULL;
- kfree(chan->dev);
- atomic_dec(idr_ref);
- goto err_out;
- }
- chan->client_count = 0;
}
- if (!chancnt) {
+ if (!device->chancnt) {
dev_err(device->dev, "%s: device has no channels!\n", __func__);
rc = -ENODEV;
goto err_out;
}
- device->chancnt = chancnt;
-
mutex_lock(&dma_list_mutex);
/* take references on public channels */
if (dmaengine_ref_count && !dma_has_cap(DMA_PRIVATE, device->cap_mask))
@@ -1080,9 +1138,8 @@ int dma_async_device_register(struct dma_device *device)
err_out:
/* if we never registered a channel just release the idr */
- if (atomic_read(idr_ref) == 0) {
+ if (!device->chancnt) {
ida_free(&dma_ida, device->dev_id);
- kfree(idr_ref);
return rc;
}
@@ -1115,16 +1172,8 @@ void dma_async_device_unregister(struct dma_device *device)
dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
- list_for_each_entry(chan, &device->channels, device_node) {
- WARN_ONCE(chan->client_count,
- "%s called while %d clients hold a reference\n",
- __func__, chan->client_count);
- mutex_lock(&dma_list_mutex);
- chan->dev->chan = NULL;
- mutex_unlock(&dma_list_mutex);
- device_unregister(&chan->dev->device);
- free_percpu(chan->local);
- }
+ list_for_each_entry(chan, &device->channels, device_node)
+ __dma_async_device_channel_unregister(device, chan);
}
EXPORT_SYMBOL(dma_async_device_unregister);
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 8fcdee1c0cf9..0202d44a17a5 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -1399,6 +1399,10 @@ static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc)
int dma_async_device_register(struct dma_device *device);
int dmaenginem_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
+int dma_async_device_channel_register(struct dma_device *device,
+ struct dma_chan *chan);
+void dma_async_device_channel_unregister(struct dma_device *device,
+ struct dma_chan *chan);
void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
next prev parent reply other threads:[~2019-12-12 18:24 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-12 18:24 [PATCH RFC v2 00/14] idxd driver for Intel Data Streaming Accelerator Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 01/14] x86/asm: add iosubmit_cmds512() based on movdir64b CPU instruction Dave Jiang
2019-12-12 18:24 ` Dave Jiang [this message]
2019-12-12 18:24 ` [PATCH RFC v2 03/14] dmaengine: add new dma device registration Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 04/14] mm: create common code from request allocation based from blk-mq code Dave Jiang
2019-12-13 0:43 ` Andrew Morton
2019-12-13 22:06 ` Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 05/14] dmaengine: add dma_request support functions Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 06/14] dmaengine: add dma request submit and completion path support Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 07/14] dmaengine: update dmatest to support dma request Dave Jiang
2019-12-12 18:24 ` [PATCH RFC v2 08/14] dmaengine: idxd: Init and probe for Intel data accelerators Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 09/14] dmaengine: idxd: add configuration component of driver Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 10/14] dmaengine: idxd: add descriptor manipulation routines Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 11/14] dmaengine: idxd: connect idxd to dmaengine subsystem Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 12/14] dmaengine: request submit optimization Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 13/14] dmaengine: idxd: add char driver to expose submission portal to userland Dave Jiang
2019-12-12 18:25 ` [PATCH RFC v2 14/14] dmaengine: idxd: add sysfs ABI for idxd driver Dave Jiang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=157617506217.42350.158281933095533374.stgit@djiang5-desk3.ch.intel.com \
--to=dave.jiang@intel.com \
--cc=akpm@linux-foundation.org \
--cc=ashok.raj@intel.com \
--cc=axboe@kernel.dk \
--cc=bp@alien8.de \
--cc=dan.j.williams@intel.com \
--cc=dmaengine@vger.kernel.org \
--cc=fenghua.yu@intel.com \
--cc=hpa@zytor.com \
--cc=jacob.jun.pan@intel.com \
--cc=jing.lin@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=megha.dey@intel.com \
--cc=mingo@redhat.com \
--cc=sanjay.k.kumar@intel.com \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=vkoul@kernel.org \
--cc=yi.l.liu@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.