From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yishai Hadas Subject: Re: [PATCH for-next 1/9] IB/core: Introduce peer client interface Date: Thu, 02 Oct 2014 17:37:33 +0300 Message-ID: <542D632D.407@dev.mellanox.co.il> References: <1412176717-11979-1-git-send-email-yishaih@mellanox.com> <1412176717-11979-2-git-send-email-yishaih@mellanox.com> <542C2D23.30508@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <542C2D23.30508-HInyCGIudOg@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Bart Van Assche , Yishai Hadas , roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, raindel-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org List-Id: linux-rdma@vger.kernel.org On 10/1/2014 7:34 PM, Bart Van Assche wrote: > On 10/01/14 17:18, Yishai Hadas wrote: >> +static int num_registered_peers; > > Is the only purpose of this variable to check whether or not > peer_memory_list is empty ? In that case please drop this variable and > use list_empty() instead. Agree. > >> +static int ib_invalidate_peer_memory(void *reg_handle, void >> *core_context) >> + >> +{ >> + return -ENOSYS; >> +} > Please follow the Linux kernel coding style which means no empty line > above the function body. OK > >> +#define PEER_MEM_MANDATORY_FUNC(x) {\ >> + offsetof(struct peer_memory_client, x), #x } > > Shouldn't the opening brace have been placed on the same line as the > offsetof() macro to improve readability ? > OK >> + if (invalidate_callback) { >> + *invalidate_callback = ib_invalidate_peer_memory; >> + ib_peer_client->invalidation_required = 1; >> + } >> + mutex_lock(&peer_memory_mutex); >> + list_add_tail(&ib_peer_client->core_peer_list, &peer_memory_list); >> + num_registered_peers++; >> + mutex_unlock(&peer_memory_mutex); >> + return ib_peer_client; > > Please insert an empty line before mutex_lock() and after mutex_unlock(). > OK >> +void ib_unregister_peer_memory_client(void *reg_handle) >> +{ >> + struct ib_peer_memory_client *ib_peer_client = >> + (struct ib_peer_memory_client *)reg_handle; > > No cast is needed when assigning a void pointer to a non-void pointer. > Agree. >> +struct peer_memory_client { >> + char name[IB_PEER_MEMORY_NAME_MAX]; >> + char version[IB_PEER_MEMORY_VER_MAX]; >> + /* The peer-direct controller (IB CORE) uses this callback to >> detect if a virtual address is under >> + * the responsibility of a specific peer direct client. If the >> answer is positive further calls >> + * for memory management will be directed to the callback of >> this peer driver. >> + * Any peer internal error should resulted in a zero answer, in >> case address range >> + * really belongs to the peer, no owner will be found and >> application will get an error >> + * from IB CORE as expected. >> + * Parameters: >> + addr [IN] - virtual address to be checked >> whether belongs to. >> + size [IN] - size of memory area starting >> at addr. >> + peer_mem_private_data [IN] - The contents of ib_ucontext-> >> peer_mem_private_data. >> + This parameter allows usage of the >> peer-direct >> + API in implementations where it is impossible >> + to detect if the memory belongs to the device >> + based upon the virtual address alone. In such >> + cases, the peer device can create a special >> + ib_ucontext, which will be associated with >> the >> + relevant peer memory. >> + peer_mem_name [IN] - The contents of ib_ucontext-> >> peer_mem_name. >> + Used to identify the peer memory client that >> + initialized the ib_ucontext. >> + This parameter is normally used along with >> + peer_mem_private_data. >> + client_context [OUT] - peer opaque data which holds a >> peer context for >> + the acquired address range, will be provided >> + back to the peer memory in subsequent >> + calls for that given memory. >> + >> + * Return value: >> + * 1 - virtual address belongs to the peer device, otherwise 0 >> + */ >> + int (*acquire)(unsigned long addr, size_t size, void >> *peer_mem_private_data, >> + char *peer_mem_name, void **client_context); >> + /* The peer memory client is expected to pin the physical pages >> of the given address range >> + * and to fill sg_table with the information of the >> + * physical pages associated with the given address range. This >> function is >> + * equivalent to the kernel API of get_user_pages(), but targets >> peer memory. >> + * Parameters: >> + addr [IN] - start virtual address of that given >> allocation. >> + size [IN] - size of memory area starting at addr. >> + write [IN] - indicates whether the pages will be >> written to by the caller. >> + Same meaning as of kernel API get_user_pages, >> can be >> + ignored if not relevant. >> + force [IN] - indicates whether to force write >> access even if user >> + mapping is readonly. Same meaning as of kernel >> API >> + get_user_pages, can be ignored if not relevant. >> + sg_head [IN/OUT] - pointer to head of struct sg_table. >> + The peer client should allocate a table big >> + enough to store all of the required entries. This >> + function should fill the table with physical >> addresses >> + and sizes of the memory segments composing this >> + memory mapping. >> + The table allocation can be done using >> sg_alloc_table. >> + Filling in the physical memory addresses and >> size can >> + be done using sg_set_page. >> + client_context [IN] - peer context for the given allocation, >> as received from >> + the acquire call. >> + core_context [IN] - opaque IB core context. If the peer >> client wishes to >> + invalidate any of the pages pinned through >> this API, >> + it must provide this context as an argument to >> the >> + invalidate callback. >> + >> + * Return value: >> + * 0 success, otherwise errno error code. >> + */ >> + int (*get_pages)(unsigned long addr, >> + size_t size, int write, int force, >> + struct sg_table *sg_head, >> + void *client_context, void *core_context); >> + /* The peer-direct controller (IB CORE) calls this function to >> request from the >> + * peer driver to fill the sg_table with dma address mapping for >> the peer memory exposed. >> + * The parameters provided have the parameters for calling >> dma_map_sg. >> + * Parameters: >> + sg_head [IN/OUT] - pointer to head of struct >> sg_table. The peer memory >> + should fill the dma_address & dma_length for >> + each scatter gather entry in the table. >> + client_context [IN] - peer context for the allocation mapped. >> + dma_device [IN] - the RDMA capable device which requires >> access to the >> + peer memory. >> + dmasync [IN] - flush in-flight DMA when the memory >> region is written. >> + Same meaning as with host memory mapping, can >> be ignored if not relevant. >> + nmap [OUT] - number of mapped/set entries. >> + >> + * Return value: >> + * 0 success, otherwise errno error code. >> + */ >> + int (*dma_map)(struct sg_table *sg_head, void *client_context, >> + struct device *dma_device, int dmasync, int *nmap); >> + /* This callback is the opposite of the dma map API, it should >> take relevant actions >> + * to unmap the memory. >> + * Parameters: >> + sg_head [IN/OUT] - pointer to head of struct >> sg_table. The peer memory >> + should fill the dma_address & dma_length for >> + each scatter gather entry in the table. >> + client_context [IN] - peer context for the allocation mapped. >> + dma_device [IN] - the RDMA capable device which requires >> access to the >> + peer memory. >> + dmasync [IN] - flush in-flight DMA when the memory >> region is written. >> + Same meaning as with host memory mapping, can >> be ignored if not relevant. >> + nmap [OUT] - number of mapped/set entries. >> + >> + * Return value: >> + * 0 success, otherwise errno error code. >> + */ >> + int (*dma_unmap)(struct sg_table *sg_head, void *client_context, >> + struct device *dma_device); >> + /* This callback is the opposite of the get_pages API, it should >> remove the pinning >> + * from the pages, it's the peer-direct equivalent of the kernel >> API put_page. >> + * Parameters: >> + sg_head [IN] - pointer to head of struct sg_table. >> + client_context [IN] - peer context for that given allocation. >> + */ >> + void (*put_pages)(struct sg_table *sg_head, void *client_context); >> + /* This callback returns page size for the given allocation >> + * Parameters: >> + sg_head [IN] - pointer to head of struct sg_table. >> + client_context [IN] - peer context for that given allocation. >> + * Return value: >> + * Page size in bytes >> + */ >> + unsigned long (*get_page_size)(void *client_context); >> + /* This callback is the opposite of the acquire call, let peer >> release all resources associated >> + * with the acquired context. The call will be performed only >> for contexts that have been >> + * successfully acquired (i.e. acquire returned a non-zero value). >> + * Parameters: >> + * client_context [IN] - peer context for the given allocation. >> + */ >> + void (*release)(void *client_context); >> + >> +}; > > All these comments inside a struct make a struct definition hard to > read. Please use kernel-doc style instead. See also > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/kernel-doc-nano-HOWTO.txt. > Thanks, will fix in next series to match the kernel-doc style. > Thanks, > > Bart. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html