From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Inform userspace how many fences are in the sync_fence_info field.
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com --- drivers/staging/android/sync.c | 2 ++ drivers/staging/android/uapi/sync.h | 2 ++ 2 files changed, 4 insertions(+)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 3a8f210..31aa462 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -525,6 +525,8 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (info->status >= 0) info->status = !info->status;
+ info->num_fences = sync_file->num_fences; + len = sizeof(struct sync_file_info);
for (i = 0; i < sync_file->num_fences; ++i) { diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index a0cf357..4ffb7cc 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -47,12 +47,14 @@ struct sync_fence_info { * userspace including pt_info. * @name: name of fence * @status: status of fence. 1: signaled 0:active <0:error + * @num_fences number of fences in the sync_file * @sync_fence_info: array of sync_fence_info for every fence in the sync_file */ struct sync_file_info { __u32 len; char name[32]; __s32 status; + __u32 num_fences;
__u8 sync_fence_info[0]; };
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
We don't use the 'fence' name to refer to sync_file anymore. So rename it to SYNC_IOC_FILE_INFO.
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com --- drivers/staging/android/sync.c | 2 +- drivers/staging/android/uapi/sync.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 31aa462..dc5f382 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -562,7 +562,7 @@ static long sync_file_ioctl(struct file *file, unsigned int cmd, case SYNC_IOC_MERGE: return sync_file_ioctl_merge(sync_file, arg);
- case SYNC_IOC_FENCE_INFO: + case SYNC_IOC_FILE_INFO: return sync_file_ioctl_fence_info(sync_file, arg);
default: diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index 4ffb7cc..dd0dd84 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -81,6 +81,6 @@ struct sync_file_info { * pt_info is a buffer containing sync_pt_infos for every sync_pt in the fence. * To iterate over the sync_pt_infos, use the sync_pt_info.len field. */ -#define SYNC_IOC_FENCE_INFO _IOWR(SYNC_IOC_MAGIC, 2, struct sync_file_info) +#define SYNC_IOC_FILE_INFO _IOWR(SYNC_IOC_MAGIC, 2, struct sync_file_info)
#endif /* _UAPI_LINUX_SYNC_H */
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
struct sync_merge_data already have documentation on top of the struct definition. No need to duplicate it.
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com --- drivers/staging/android/uapi/sync.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index dd0dd84..f0b41ce 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -21,9 +21,9 @@ * @fence: returns the fd of the new fence to userspace */ struct sync_merge_data { - __s32 fd2; /* fd of second fence */ - char name[32]; /* name of new fence */ - __s32 fence; /* fd on newly created fence */ + __s32 fd2; + char name[32]; + __s32 fence; };
/**
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Change SYNC_IOC_FILE_INFO behaviour to avoid future API breaks and optimize buffer
Now num_fences can be filled by the caller to inform how many fences it wants to retrieve from the kernel. If the num_fences passed is greater than zero info->sync_fence_info should point to a buffer with enough space to fit all fences.
However if num_fences passed to the kernel is 0, the kernel will reply with number of fences of the sync_file.
Sending first an ioctl with num_fences = 0 can optimize buffer allocation, in a first call with num_fences = 0 userspace will receive the actual number of fences in the num_fences filed.
Then it can allocate a buffer with the correct size on sync_fence_info and call SYNC_IOC_FILE_INFO again, but now with the actual value of num_fences in the sync_file.
Also, info->sync_fence_info was converted to __u64 pointer to prevent 32bit compatibility issues.
An example userspace code for the later would be:
struct sync_file_info *info; int err, size, num_fences;
info = malloc(sizeof(*info));
info.flags = 0; err = ioctl(fd, SYNC_IOC_FILE_INFO, info); num_fences = info->num_fences;
if (num_fences) { info.flags = 0; size = sizeof(struct sync_fence_info) * num_fences; info->num_fences = num_fences; info->sync_fence_info = (uint64_t) calloc(num_fences, sizeof(struct sync_fence_info));
err = ioctl(fd, SYNC_IOC_FILE_INFO, info); }
v2: fix fence_info memory leak
v3: Comments from Emil Velikov - improve commit message - remove __u64 cast - remove check for output fields in file_info - clean up sync_fill_fence_info()
Comments from Maarten Lankhorst - remove in.num_fences && !in.sync_fence_info check - remove info->len and use only num_fences to calculate size
Comments from Dan Carpenter - fix info->sync_fence_info documentation
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk --- drivers/staging/android/sync.c | 64 ++++++++++++++++++++----------------- drivers/staging/android/uapi/sync.h | 9 ++---- 2 files changed, 38 insertions(+), 35 deletions(-)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index dc5f382..3604e453 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -479,13 +479,9 @@ err_put_fd: return err; }
-static int sync_fill_fence_info(struct fence *fence, void *data, int size) +static void sync_fill_fence_info(struct fence *fence, + struct sync_fence_info *info) { - struct sync_fence_info *info = data; - - if (size < sizeof(*info)) - return -ENOMEM; - strlcpy(info->obj_name, fence->ops->get_timeline_name(fence), sizeof(info->obj_name)); strlcpy(info->driver_name, fence->ops->get_driver_name(fence), @@ -495,28 +491,20 @@ static int sync_fill_fence_info(struct fence *fence, void *data, int size) else info->status = 0; info->timestamp_ns = ktime_to_ns(fence->timestamp); - - return sizeof(*info); }
static long sync_file_ioctl_fence_info(struct sync_file *sync_file, unsigned long arg) { - struct sync_file_info *info; + struct sync_file_info in, *info; + struct sync_fence_info *fence_info = NULL; __u32 size; - __u32 len = 0; int ret, i;
- if (copy_from_user(&size, (void __user *)arg, sizeof(size))) + if (copy_from_user(&in, (void __user *)arg, sizeof(in))) return -EFAULT;
- if (size < sizeof(struct sync_file_info)) - return -EINVAL; - - if (size > 4096) - size = 4096; - - info = kzalloc(size, GFP_KERNEL); + info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM;
@@ -525,29 +513,47 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (info->status >= 0) info->status = !info->status;
- info->num_fences = sync_file->num_fences; - - len = sizeof(struct sync_file_info); + /* + * Passing num_fences = 0 means that userspace doesn't want to + * retrieve any sync_fence_info. If num_fences = 0 we skip filling + * sync_fence_info and return the actual number of fences on + * info->num_fences. + */ + if (!in.num_fences) + goto no_fences;
- for (i = 0; i < sync_file->num_fences; ++i) { - struct fence *fence = sync_file->cbs[i].fence; + if (in.num_fences < sync_file->num_fences) { + ret = -EINVAL; + goto out; + }
- ret = sync_fill_fence_info(fence, (u8 *)info + len, size - len); + size = sync_file->num_fences * sizeof(*fence_info); + fence_info = kzalloc(size, GFP_KERNEL); + if (!fence_info) { + ret = -ENOMEM; + goto out; + }
- if (ret < 0) - goto out; + for (i = 0; i < sync_file->num_fences; ++i) + sync_fill_fence_info(sync_file->cbs[i].fence, &fence_info[i]);
- len += ret; + if (copy_to_user((void __user *)in.sync_fence_info, fence_info, size)) { + ret = -EFAULT; + goto out; }
- info->len = len; + info->sync_fence_info = in.sync_fence_info; + +no_fences: + info->num_fences = sync_file->num_fences;
- if (copy_to_user((void __user *)arg, info, len)) + if (copy_to_user((void __user *)arg, info, sizeof(*info))) ret = -EFAULT; else ret = 0;
out: + kfree(fence_info); kfree(info);
return ret; diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index f0b41ce..a122bb5 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -42,21 +42,18 @@ struct sync_fence_info {
/** * struct sync_file_info - data returned from fence info ioctl - * @len: ioctl caller writes the size of the buffer its passing in. - * ioctl returns length of sync_file_info returned to - * userspace including pt_info. * @name: name of fence * @status: status of fence. 1: signaled 0:active <0:error * @num_fences number of fences in the sync_file - * @sync_fence_info: array of sync_fence_info for every fence in the sync_file + * @sync_fence_info: pointer to array of structs sync_fence_info with all + * fences in the sync_file */ struct sync_file_info { - __u32 len; char name[32]; __s32 status; __u32 num_fences;
- __u8 sync_fence_info[0]; + __u64 sync_fence_info; };
#define SYNC_IOC_MAGIC '>'
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Play safe and add flags member to all structs. So we don't need to break API or create new IOCTL in the future if new features that requires flags arises.
v2: check if flags are valid (zero, in this case)
v3: return -EINVAL if flags are not zero'ed
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk --- drivers/staging/android/sync.c | 8 ++++++++ drivers/staging/android/uapi/sync.h | 6 ++++++ 2 files changed, 14 insertions(+)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 3604e453..3c265ed 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -445,6 +445,11 @@ static long sync_file_ioctl_merge(struct sync_file *sync_file, goto err_put_fd; }
+ if (data.flags) { + err = -EINVAL; + goto err_put_fd; + } + fence2 = sync_file_fdget(data.fd2); if (!fence2) { err = -ENOENT; @@ -504,6 +509,9 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (copy_from_user(&in, (void __user *)arg, sizeof(in))) return -EFAULT;
+ if (in.flags) + return -EINVAL; + info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM; diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index a122bb5..11e2d28 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -19,11 +19,13 @@ * @fd2: file descriptor of second fence * @name: name of new fence * @fence: returns the fd of the new fence to userspace + * @flags: merge_data flags */ struct sync_merge_data { __s32 fd2; char name[32]; __s32 fence; + __u32 flags; };
/** @@ -31,12 +33,14 @@ struct sync_merge_data { * @obj_name: name of parent sync_timeline * @driver_name: name of driver implementing the parent * @status: status of the fence 0:active 1:signaled <0:error + * @flags: fence_info flags * @timestamp_ns: timestamp of status change in nanoseconds */ struct sync_fence_info { char obj_name[32]; char driver_name[32]; __s32 status; + __u32 flags; __u64 timestamp_ns; };
@@ -44,6 +48,7 @@ struct sync_fence_info { * struct sync_file_info - data returned from fence info ioctl * @name: name of fence * @status: status of fence. 1: signaled 0:active <0:error + * @flags: sync_file_info flags * @num_fences number of fences in the sync_file * @sync_fence_info: pointer to array of structs sync_fence_info with all * fences in the sync_file @@ -51,6 +56,7 @@ struct sync_fence_info { struct sync_file_info { char name[32]; __s32 status; + __u32 flags; __u32 num_fences;
__u64 sync_fence_info;
On 1 March 2016 at 13:13, Gustavo Padovan gustavo@padovan.org wrote:
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Play safe and add flags member to all structs. So we don't need to break API or create new IOCTL in the future if new features that requires flags arises.
v2: check if flags are valid (zero, in this case)
v3: return -EINVAL if flags are not zero'ed
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk
drivers/staging/android/sync.c | 8 ++++++++ drivers/staging/android/uapi/sync.h | 6 ++++++ 2 files changed, 14 insertions(+)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 3604e453..3c265ed 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -445,6 +445,11 @@ static long sync_file_ioctl_merge(struct sync_file *sync_file, goto err_put_fd; }
if (data.flags) {err = -EINVAL;goto err_put_fd;}fence2 = sync_file_fdget(data.fd2); if (!fence2) { err = -ENOENT;@@ -504,6 +509,9 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (copy_from_user(&in, (void __user *)arg, sizeof(in))) return -EFAULT;
if (in.flags)return -EINVAL;info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM;diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index a122bb5..11e2d28 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -19,11 +19,13 @@
- @fd2: file descriptor of second fence
- @name: name of new fence
- @fence: returns the fd of the new fence to userspace
*/
- @flags: merge_data flags
struct sync_merge_data { __s32 fd2; char name[32]; __s32 fence;
__u32 flags;
The comment from last round still stands, struct size must be multiple of 64bits. As is the struct will be broken whenever/if we decide to extend it. See [1] for an alternative wording.
};
/** @@ -31,12 +33,14 @@ struct sync_merge_data {
- @obj_name: name of parent sync_timeline
- @driver_name: name of driver implementing the parent
- @status: status of the fence 0:active 1:signaled <0:error
*/
- @flags: fence_info flags
- @timestamp_ns: timestamp of status change in nanoseconds
struct sync_fence_info { char obj_name[32]; char driver_name[32]; __s32 status;
__u32 flags; __u64 timestamp_ns;};
@@ -44,6 +48,7 @@ struct sync_fence_info {
- struct sync_file_info - data returned from fence info ioctl
- @name: name of fence
- @status: status of fence. 1: signaled 0:active <0:error
- @flags: sync_file_info flags
- @num_fences number of fences in the sync_file
- @sync_fence_info: pointer to array of structs sync_fence_info with all
fences in the sync_file@@ -51,6 +56,7 @@ struct sync_fence_info { struct sync_file_info { char name[32]; __s32 status;
__u32 flags; __u32 num_fences; __u64 sync_fence_info;
Thanks for taking my suggestion and dropping len. Although I fear that we introduced a hole which we should be explicitly padded [2].
In both cases the pad should be checked for 0 and -EINVAL should be returned if that's not the case. This will allow us to potentially reuse in the future.
Other than that I believe the series looks pretty much spot on.
Cheers, Emil
[1] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documen... [2] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documen...
Hi Emil,
2016-03-02 Emil Velikov emil.l.velikov@gmail.com:
On 1 March 2016 at 13:13, Gustavo Padovan gustavo@padovan.org wrote:
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Play safe and add flags member to all structs. So we don't need to break API or create new IOCTL in the future if new features that requires flags arises.
v2: check if flags are valid (zero, in this case)
v3: return -EINVAL if flags are not zero'ed
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk
drivers/staging/android/sync.c | 8 ++++++++ drivers/staging/android/uapi/sync.h | 6 ++++++ 2 files changed, 14 insertions(+)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 3604e453..3c265ed 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -445,6 +445,11 @@ static long sync_file_ioctl_merge(struct sync_file *sync_file, goto err_put_fd; }
if (data.flags) {err = -EINVAL;goto err_put_fd;}fence2 = sync_file_fdget(data.fd2); if (!fence2) { err = -ENOENT;@@ -504,6 +509,9 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (copy_from_user(&in, (void __user *)arg, sizeof(in))) return -EFAULT;
if (in.flags)return -EINVAL;info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM;diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index a122bb5..11e2d28 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -19,11 +19,13 @@
- @fd2: file descriptor of second fence
- @name: name of new fence
- @fence: returns the fd of the new fence to userspace
*/
- @flags: merge_data flags
struct sync_merge_data { __s32 fd2; char name[32]; __s32 fence;
__u32 flags;The comment from last round still stands, struct size must be multiple of 64bits. As is the struct will be broken whenever/if we decide to extend it. See [1] for an alternative wording.
};
/** @@ -31,12 +33,14 @@ struct sync_merge_data {
- @obj_name: name of parent sync_timeline
- @driver_name: name of driver implementing the parent
- @status: status of the fence 0:active 1:signaled <0:error
*/
- @flags: fence_info flags
- @timestamp_ns: timestamp of status change in nanoseconds
struct sync_fence_info { char obj_name[32]; char driver_name[32]; __s32 status;
__u32 flags; __u64 timestamp_ns;};
@@ -44,6 +48,7 @@ struct sync_fence_info {
- struct sync_file_info - data returned from fence info ioctl
- @name: name of fence
- @status: status of fence. 1: signaled 0:active <0:error
- @flags: sync_file_info flags
- @num_fences number of fences in the sync_file
- @sync_fence_info: pointer to array of structs sync_fence_info with all
fences in the sync_file@@ -51,6 +56,7 @@ struct sync_fence_info { struct sync_file_info { char name[32]; __s32 status;
__u32 flags; __u32 num_fences; __u64 sync_fence_info;Thanks for taking my suggestion and dropping len. Although I fear that we introduced a hole which we should be explicitly padded [2].
In both cases the pad should be checked for 0 and -EINVAL should be returned if that's not the case. This will allow us to potentially reuse in the future.
Other than that I believe the series looks pretty much spot on.
I agree with both suggestions, a new version of the patches is on the way.
Gustavo
dri-devel@lists.freedesktop.org
-
Emil Velikov -
Gustavo Padovan