On 5/4/2023 10:34 AM, Jason Gunthorpe wrote:
Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding. On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:+static struct pds_vfio_lm_file * +pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size) +{ + struct pds_vfio_lm_file *lm_file = NULL; + unsigned long long npages; + struct page **pages; + int err = 0; + + if (!size) + return NULL; + + /* Alloc file structure */ + lm_file = kzalloc(sizeof(*lm_file), GFP_KERNEL); + if (!lm_file) + return NULL; + + /* Create file */ + lm_file->filep = anon_inode_getfile("pds_vfio_lm", fops, lm_file, flags); + if (!lm_file->filep) + goto err_get_file; + + stream_open(lm_file->filep->f_inode, lm_file->filep); + mutex_init(&lm_file->lock); + + lm_file->size = size; + + /* Allocate memory for file pages */ + npages = DIV_ROUND_UP_ULL(lm_file->size, PAGE_SIZE); + + pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL); + if (!pages) + goto err_alloc_pages; + + for (unsigned long long i = 0; i < npages; i++) { + pages[i] = alloc_page(GFP_KERNEL); + if (!pages[i]) + goto err_alloc_page; + } + + lm_file->pages = pages; + lm_file->npages = npages; + lm_file->alloc_size = npages * PAGE_SIZE; + + /* Create scatterlist of file pages to use for DMA mapping later */ + err = sg_alloc_table_from_pages(&lm_file->sg_table, pages, npages, + 0, size, GFP_KERNEL); + if (err) + goto err_alloc_sg_table; + + /* prevent file from being released before we are done with it */ + get_file(lm_file->filep); + + return lm_file; + +err_alloc_sg_table: +err_alloc_page:What is with these double error out labels? I see it in a few places, that is not the kernel style. In VFIO we have been trying to label the err outs based on what they free, it is not a 'call from' scheme. Jason
Yeah this is kind of ugly. Thanks for pointing it out. I will fix it and any other occurrences in the next revision.
Brett
