15b497af4SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 27b6be844SDan Williams /* 37b6be844SDan Williams * Copyright(c) 2017 Intel Corporation. All rights reserved. 47b6be844SDan Williams */ 57b6be844SDan Williams #include <linux/pagemap.h> 67b6be844SDan Williams #include <linux/module.h> 77b6be844SDan Williams #include <linux/mount.h> 875d4e06fSDavid Howells #include <linux/pseudo_fs.h> 97b6be844SDan Williams #include <linux/magic.h> 10569d0365SDan Williams #include <linux/pfn_t.h> 117b6be844SDan Williams #include <linux/cdev.h> 127b6be844SDan Williams #include <linux/slab.h> 137e026c8cSDan Williams #include <linux/uio.h> 146568b08bSDan Williams #include <linux/dax.h> 157b6be844SDan Williams #include <linux/fs.h> 1651cf784cSDan Williams #include "dax-private.h" 177b6be844SDan Williams 181b764601SChristoph Hellwig /** 191b764601SChristoph Hellwig * struct dax_device - anchor object for dax services 201b764601SChristoph Hellwig * @inode: core vfs 211b764601SChristoph Hellwig * @cdev: optional character interface for "device dax" 221b764601SChristoph Hellwig * @private: dax driver private data 231b764601SChristoph Hellwig * @flags: state and boolean properties 241b764601SChristoph Hellwig */ 251b764601SChristoph Hellwig struct dax_device { 261b764601SChristoph Hellwig struct inode inode; 271b764601SChristoph Hellwig struct cdev cdev; 281b764601SChristoph Hellwig void *private; 291b764601SChristoph Hellwig unsigned long flags; 301b764601SChristoph Hellwig const struct dax_operations *ops; 311b764601SChristoph Hellwig }; 321b764601SChristoph Hellwig 337b6be844SDan Williams static dev_t dax_devt; 347b6be844SDan Williams DEFINE_STATIC_SRCU(dax_srcu); 357b6be844SDan Williams static struct vfsmount *dax_mnt; 367b6be844SDan Williams static DEFINE_IDA(dax_minor_ida); 377b6be844SDan Williams static struct kmem_cache *dax_cache __read_mostly; 387b6be844SDan Williams static struct super_block *dax_superblock __read_mostly; 397b6be844SDan Williams 407b6be844SDan Williams int dax_read_lock(void) 417b6be844SDan Williams { 427b6be844SDan Williams return srcu_read_lock(&dax_srcu); 437b6be844SDan Williams } 447b6be844SDan Williams EXPORT_SYMBOL_GPL(dax_read_lock); 457b6be844SDan Williams 467b6be844SDan Williams void dax_read_unlock(int id) 477b6be844SDan Williams { 487b6be844SDan Williams srcu_read_unlock(&dax_srcu, id); 497b6be844SDan Williams } 507b6be844SDan Williams EXPORT_SYMBOL_GPL(dax_read_unlock); 517b6be844SDan Williams 525d2a228bSChristoph Hellwig #if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX) 53e765f13eSChristoph Hellwig #include <linux/blkdev.h> 54e765f13eSChristoph Hellwig 55fb08a190SChristoph Hellwig static DEFINE_XARRAY(dax_hosts); 56fb08a190SChristoph Hellwig 57fb08a190SChristoph Hellwig int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk) 58fb08a190SChristoph Hellwig { 59fb08a190SChristoph Hellwig return xa_insert(&dax_hosts, (unsigned long)disk, dax_dev, GFP_KERNEL); 60fb08a190SChristoph Hellwig } 61fb08a190SChristoph Hellwig EXPORT_SYMBOL_GPL(dax_add_host); 62fb08a190SChristoph Hellwig 63fb08a190SChristoph Hellwig void dax_remove_host(struct gendisk *disk) 64fb08a190SChristoph Hellwig { 65fb08a190SChristoph Hellwig xa_erase(&dax_hosts, (unsigned long)disk); 66fb08a190SChristoph Hellwig } 67fb08a190SChristoph Hellwig EXPORT_SYMBOL_GPL(dax_remove_host); 68fb08a190SChristoph Hellwig 691b764601SChristoph Hellwig /** 70fb08a190SChristoph Hellwig * fs_dax_get_by_bdev() - temporary lookup mechanism for filesystem-dax 71fb08a190SChristoph Hellwig * @bdev: block device to find a dax_device for 72cd913c76SChristoph Hellwig * @start_off: returns the byte offset into the dax_device that @bdev starts 731b764601SChristoph Hellwig */ 74cd913c76SChristoph Hellwig struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off) 7578f35473SDan Williams { 76fb08a190SChristoph Hellwig struct dax_device *dax_dev; 77cd913c76SChristoph Hellwig u64 part_size; 78fb08a190SChristoph Hellwig int id; 79fb08a190SChristoph Hellwig 80e556f6baSChristoph Hellwig if (!blk_queue_dax(bdev->bd_disk->queue)) 8178f35473SDan Williams return NULL; 82fb08a190SChristoph Hellwig 83cd913c76SChristoph Hellwig *start_off = get_start_sect(bdev) * SECTOR_SIZE; 84cd913c76SChristoph Hellwig part_size = bdev_nr_sectors(bdev) * SECTOR_SIZE; 85cd913c76SChristoph Hellwig if (*start_off % PAGE_SIZE || part_size % PAGE_SIZE) { 860c445871SChristoph Hellwig pr_info("%pg: error: unaligned partition for dax\n", bdev); 870c445871SChristoph Hellwig return NULL; 880c445871SChristoph Hellwig } 890c445871SChristoph Hellwig 90fb08a190SChristoph Hellwig id = dax_read_lock(); 91fb08a190SChristoph Hellwig dax_dev = xa_load(&dax_hosts, (unsigned long)bdev->bd_disk); 92fb08a190SChristoph Hellwig if (!dax_dev || !dax_alive(dax_dev) || !igrab(&dax_dev->inode)) 93fb08a190SChristoph Hellwig dax_dev = NULL; 94fb08a190SChristoph Hellwig dax_read_unlock(id); 95fb08a190SChristoph Hellwig 96fb08a190SChristoph Hellwig return dax_dev; 9778f35473SDan Williams } 9878f35473SDan Williams EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); 995d2a228bSChristoph Hellwig #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ 100ef510424SDan Williams 1019a60c3efSDan Williams enum dax_device_flags { 1029a60c3efSDan Williams /* !alive + rcu grace period == no new operations / mappings */ 1039a60c3efSDan Williams DAXDEV_ALIVE, 1046e0c90d6SDan Williams /* gate whether dax_flush() calls the low level flush routine */ 1056e0c90d6SDan Williams DAXDEV_WRITE_CACHE, 106fefc1d97SPankaj Gupta /* flag to check if device supports synchronous flush */ 107fefc1d97SPankaj Gupta DAXDEV_SYNC, 1089a60c3efSDan Williams }; 1099a60c3efSDan Williams 110b0686260SDan Williams /** 111b0686260SDan Williams * dax_direct_access() - translate a device pgoff to an absolute pfn 112b0686260SDan Williams * @dax_dev: a dax_device instance representing the logical memory range 113b0686260SDan Williams * @pgoff: offset in pages from the start of the device to translate 114b0686260SDan Williams * @nr_pages: number of consecutive pages caller can handle relative to @pfn 115b0686260SDan Williams * @kaddr: output parameter that returns a virtual address mapping of pfn 116b0686260SDan Williams * @pfn: output parameter that returns an absolute pfn translation of @pgoff 117b0686260SDan Williams * 118b0686260SDan Williams * Return: negative errno if an error occurs, otherwise the number of 119b0686260SDan Williams * pages accessible at the device relative @pgoff. 120b0686260SDan Williams */ 121b0686260SDan Williams long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages, 122b0686260SDan Williams void **kaddr, pfn_t *pfn) 123b0686260SDan Williams { 124b0686260SDan Williams long avail; 125b0686260SDan Williams 126b0686260SDan Williams if (!dax_dev) 127b0686260SDan Williams return -EOPNOTSUPP; 128b0686260SDan Williams 129b0686260SDan Williams if (!dax_alive(dax_dev)) 130b0686260SDan Williams return -ENXIO; 131b0686260SDan Williams 132b0686260SDan Williams if (nr_pages < 0) 133b05d4c57SIra Weiny return -EINVAL; 134b0686260SDan Williams 135b0686260SDan Williams avail = dax_dev->ops->direct_access(dax_dev, pgoff, nr_pages, 136b0686260SDan Williams kaddr, pfn); 137b0686260SDan Williams if (!avail) 138b0686260SDan Williams return -ERANGE; 139b0686260SDan Williams return min(avail, nr_pages); 140b0686260SDan Williams } 141b0686260SDan Williams EXPORT_SYMBOL_GPL(dax_direct_access); 142b0686260SDan Williams 1437e026c8cSDan Williams size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, 1447e026c8cSDan Williams size_t bytes, struct iov_iter *i) 1457e026c8cSDan Williams { 1467e026c8cSDan Williams if (!dax_alive(dax_dev)) 1477e026c8cSDan Williams return 0; 1487e026c8cSDan Williams 1497e026c8cSDan Williams return dax_dev->ops->copy_from_iter(dax_dev, pgoff, addr, bytes, i); 1507e026c8cSDan Williams } 1517e026c8cSDan Williams EXPORT_SYMBOL_GPL(dax_copy_from_iter); 1527e026c8cSDan Williams 153b3a9a0c3SDan Williams size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, 154b3a9a0c3SDan Williams size_t bytes, struct iov_iter *i) 155b3a9a0c3SDan Williams { 156b3a9a0c3SDan Williams if (!dax_alive(dax_dev)) 157b3a9a0c3SDan Williams return 0; 158b3a9a0c3SDan Williams 159b3a9a0c3SDan Williams return dax_dev->ops->copy_to_iter(dax_dev, pgoff, addr, bytes, i); 160b3a9a0c3SDan Williams } 161b3a9a0c3SDan Williams EXPORT_SYMBOL_GPL(dax_copy_to_iter); 162b3a9a0c3SDan Williams 163f605a263SVivek Goyal int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff, 164f605a263SVivek Goyal size_t nr_pages) 165f605a263SVivek Goyal { 166f605a263SVivek Goyal if (!dax_alive(dax_dev)) 167f605a263SVivek Goyal return -ENXIO; 168f605a263SVivek Goyal /* 169f605a263SVivek Goyal * There are no callers that want to zero more than one page as of now. 170f605a263SVivek Goyal * Once users are there, this check can be removed after the 171f605a263SVivek Goyal * device mapper code has been updated to split ranges across targets. 172f605a263SVivek Goyal */ 173f605a263SVivek Goyal if (nr_pages != 1) 174f605a263SVivek Goyal return -EIO; 175f605a263SVivek Goyal 176f605a263SVivek Goyal return dax_dev->ops->zero_page_range(dax_dev, pgoff, nr_pages); 177f605a263SVivek Goyal } 178f605a263SVivek Goyal EXPORT_SYMBOL_GPL(dax_zero_page_range); 179f605a263SVivek Goyal 180c3ca015fSMikulas Patocka #ifdef CONFIG_ARCH_HAS_PMEM_API 181c3ca015fSMikulas Patocka void arch_wb_cache_pmem(void *addr, size_t size); 182c3ca015fSMikulas Patocka void dax_flush(struct dax_device *dax_dev, void *addr, size_t size) 183abebfbe2SDan Williams { 184808c340bSRoss Zwisler if (unlikely(!dax_write_cache_enabled(dax_dev))) 1856e0c90d6SDan Williams return; 1866e0c90d6SDan Williams 187c3ca015fSMikulas Patocka arch_wb_cache_pmem(addr, size); 188abebfbe2SDan Williams } 189c3ca015fSMikulas Patocka #else 190c3ca015fSMikulas Patocka void dax_flush(struct dax_device *dax_dev, void *addr, size_t size) 191c3ca015fSMikulas Patocka { 192c3ca015fSMikulas Patocka } 193c3ca015fSMikulas Patocka #endif 194abebfbe2SDan Williams EXPORT_SYMBOL_GPL(dax_flush); 195abebfbe2SDan Williams 1966e0c90d6SDan Williams void dax_write_cache(struct dax_device *dax_dev, bool wc) 1976e0c90d6SDan Williams { 1986e0c90d6SDan Williams if (wc) 1996e0c90d6SDan Williams set_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); 2006e0c90d6SDan Williams else 2016e0c90d6SDan Williams clear_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); 2026e0c90d6SDan Williams } 2036e0c90d6SDan Williams EXPORT_SYMBOL_GPL(dax_write_cache); 2046e0c90d6SDan Williams 205273752c9SVivek Goyal bool dax_write_cache_enabled(struct dax_device *dax_dev) 206273752c9SVivek Goyal { 207273752c9SVivek Goyal return test_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); 208273752c9SVivek Goyal } 209273752c9SVivek Goyal EXPORT_SYMBOL_GPL(dax_write_cache_enabled); 210273752c9SVivek Goyal 211fd1d00ecSChristoph Hellwig bool dax_synchronous(struct dax_device *dax_dev) 212fefc1d97SPankaj Gupta { 213fefc1d97SPankaj Gupta return test_bit(DAXDEV_SYNC, &dax_dev->flags); 214fefc1d97SPankaj Gupta } 215fd1d00ecSChristoph Hellwig EXPORT_SYMBOL_GPL(dax_synchronous); 216fefc1d97SPankaj Gupta 217fd1d00ecSChristoph Hellwig void set_dax_synchronous(struct dax_device *dax_dev) 218fefc1d97SPankaj Gupta { 219fefc1d97SPankaj Gupta set_bit(DAXDEV_SYNC, &dax_dev->flags); 220fefc1d97SPankaj Gupta } 221fd1d00ecSChristoph Hellwig EXPORT_SYMBOL_GPL(set_dax_synchronous); 222fefc1d97SPankaj Gupta 2237b6be844SDan Williams bool dax_alive(struct dax_device *dax_dev) 2247b6be844SDan Williams { 2257b6be844SDan Williams lockdep_assert_held(&dax_srcu); 2269a60c3efSDan Williams return test_bit(DAXDEV_ALIVE, &dax_dev->flags); 2277b6be844SDan Williams } 2287b6be844SDan Williams EXPORT_SYMBOL_GPL(dax_alive); 2297b6be844SDan Williams 2307b6be844SDan Williams /* 2317b6be844SDan Williams * Note, rcu is not protecting the liveness of dax_dev, rcu is ensuring 2327b6be844SDan Williams * that any fault handlers or operations that might have seen 2337b6be844SDan Williams * dax_alive(), have completed. Any operations that start after 2347b6be844SDan Williams * synchronize_srcu() has run will abort upon seeing !dax_alive(). 2357b6be844SDan Williams */ 2367b6be844SDan Williams void kill_dax(struct dax_device *dax_dev) 2377b6be844SDan Williams { 2387b6be844SDan Williams if (!dax_dev) 2397b6be844SDan Williams return; 2407b6be844SDan Williams 2419a60c3efSDan Williams clear_bit(DAXDEV_ALIVE, &dax_dev->flags); 2427b6be844SDan Williams synchronize_srcu(&dax_srcu); 2437b6be844SDan Williams } 2447b6be844SDan Williams EXPORT_SYMBOL_GPL(kill_dax); 2457b6be844SDan Williams 2469567da0bSDan Williams void run_dax(struct dax_device *dax_dev) 2479567da0bSDan Williams { 2489567da0bSDan Williams set_bit(DAXDEV_ALIVE, &dax_dev->flags); 2499567da0bSDan Williams } 2509567da0bSDan Williams EXPORT_SYMBOL_GPL(run_dax); 2519567da0bSDan Williams 2527b6be844SDan Williams static struct inode *dax_alloc_inode(struct super_block *sb) 2537b6be844SDan Williams { 2547b6be844SDan Williams struct dax_device *dax_dev; 255b9d39d17SDan Williams struct inode *inode; 2567b6be844SDan Williams 2577b6be844SDan Williams dax_dev = kmem_cache_alloc(dax_cache, GFP_KERNEL); 2589f586fffSMikulas Patocka if (!dax_dev) 2599f586fffSMikulas Patocka return NULL; 2609f586fffSMikulas Patocka 261b9d39d17SDan Williams inode = &dax_dev->inode; 262b9d39d17SDan Williams inode->i_rdev = 0; 263b9d39d17SDan Williams return inode; 2647b6be844SDan Williams } 2657b6be844SDan Williams 2667b6be844SDan Williams static struct dax_device *to_dax_dev(struct inode *inode) 2677b6be844SDan Williams { 2687b6be844SDan Williams return container_of(inode, struct dax_device, inode); 2697b6be844SDan Williams } 2707b6be844SDan Williams 27153e22829SAl Viro static void dax_free_inode(struct inode *inode) 2727b6be844SDan Williams { 2737b6be844SDan Williams struct dax_device *dax_dev = to_dax_dev(inode); 274b9d39d17SDan Williams if (inode->i_rdev) 2756f24784fSAl Viro ida_simple_remove(&dax_minor_ida, iminor(inode)); 2767b6be844SDan Williams kmem_cache_free(dax_cache, dax_dev); 2777b6be844SDan Williams } 2787b6be844SDan Williams 2797b6be844SDan Williams static void dax_destroy_inode(struct inode *inode) 2807b6be844SDan Williams { 2817b6be844SDan Williams struct dax_device *dax_dev = to_dax_dev(inode); 2829a60c3efSDan Williams WARN_ONCE(test_bit(DAXDEV_ALIVE, &dax_dev->flags), 2837b6be844SDan Williams "kill_dax() must be called before final iput()\n"); 2847b6be844SDan Williams } 2857b6be844SDan Williams 2867b6be844SDan Williams static const struct super_operations dax_sops = { 2877b6be844SDan Williams .statfs = simple_statfs, 2887b6be844SDan Williams .alloc_inode = dax_alloc_inode, 2897b6be844SDan Williams .destroy_inode = dax_destroy_inode, 29053e22829SAl Viro .free_inode = dax_free_inode, 2917b6be844SDan Williams .drop_inode = generic_delete_inode, 2927b6be844SDan Williams }; 2937b6be844SDan Williams 29475d4e06fSDavid Howells static int dax_init_fs_context(struct fs_context *fc) 2957b6be844SDan Williams { 29675d4e06fSDavid Howells struct pseudo_fs_context *ctx = init_pseudo(fc, DAXFS_MAGIC); 29775d4e06fSDavid Howells if (!ctx) 29875d4e06fSDavid Howells return -ENOMEM; 29975d4e06fSDavid Howells ctx->ops = &dax_sops; 30075d4e06fSDavid Howells return 0; 3017b6be844SDan Williams } 3027b6be844SDan Williams 3037b6be844SDan Williams static struct file_system_type dax_fs_type = { 3047b6be844SDan Williams .name = "dax", 30575d4e06fSDavid Howells .init_fs_context = dax_init_fs_context, 3067b6be844SDan Williams .kill_sb = kill_anon_super, 3077b6be844SDan Williams }; 3087b6be844SDan Williams 3097b6be844SDan Williams static int dax_test(struct inode *inode, void *data) 3107b6be844SDan Williams { 3117b6be844SDan Williams dev_t devt = *(dev_t *) data; 3127b6be844SDan Williams 3137b6be844SDan Williams return inode->i_rdev == devt; 3147b6be844SDan Williams } 3157b6be844SDan Williams 3167b6be844SDan Williams static int dax_set(struct inode *inode, void *data) 3177b6be844SDan Williams { 3187b6be844SDan Williams dev_t devt = *(dev_t *) data; 3197b6be844SDan Williams 3207b6be844SDan Williams inode->i_rdev = devt; 3217b6be844SDan Williams return 0; 3227b6be844SDan Williams } 3237b6be844SDan Williams 3247b6be844SDan Williams static struct dax_device *dax_dev_get(dev_t devt) 3257b6be844SDan Williams { 3267b6be844SDan Williams struct dax_device *dax_dev; 3277b6be844SDan Williams struct inode *inode; 3287b6be844SDan Williams 3297b6be844SDan Williams inode = iget5_locked(dax_superblock, hash_32(devt + DAXFS_MAGIC, 31), 3307b6be844SDan Williams dax_test, dax_set, &devt); 3317b6be844SDan Williams 3327b6be844SDan Williams if (!inode) 3337b6be844SDan Williams return NULL; 3347b6be844SDan Williams 3357b6be844SDan Williams dax_dev = to_dax_dev(inode); 3367b6be844SDan Williams if (inode->i_state & I_NEW) { 3379a60c3efSDan Williams set_bit(DAXDEV_ALIVE, &dax_dev->flags); 3387b6be844SDan Williams inode->i_cdev = &dax_dev->cdev; 3397b6be844SDan Williams inode->i_mode = S_IFCHR; 3407b6be844SDan Williams inode->i_flags = S_DAX; 3417b6be844SDan Williams mapping_set_gfp_mask(&inode->i_data, GFP_USER); 3427b6be844SDan Williams unlock_new_inode(inode); 3437b6be844SDan Williams } 3447b6be844SDan Williams 3457b6be844SDan Williams return dax_dev; 3467b6be844SDan Williams } 3477b6be844SDan Williams 348*30c6828aSChristoph Hellwig struct dax_device *alloc_dax(void *private, const struct dax_operations *ops) 3497b6be844SDan Williams { 3507b6be844SDan Williams struct dax_device *dax_dev; 3517b6be844SDan Williams dev_t devt; 3527b6be844SDan Williams int minor; 3537b6be844SDan Williams 354fb08a190SChristoph Hellwig if (WARN_ON_ONCE(ops && !ops->zero_page_range)) 3554e4ced93SVivek Goyal return ERR_PTR(-EINVAL); 35672058005SDan Williams 357cf1e2289SDan Williams minor = ida_simple_get(&dax_minor_ida, 0, MINORMASK+1, GFP_KERNEL); 3587b6be844SDan Williams if (minor < 0) 359fb08a190SChristoph Hellwig return ERR_PTR(-ENOMEM); 3607b6be844SDan Williams 3617b6be844SDan Williams devt = MKDEV(MAJOR(dax_devt), minor); 3627b6be844SDan Williams dax_dev = dax_dev_get(devt); 3637b6be844SDan Williams if (!dax_dev) 36472058005SDan Williams goto err_dev; 3657b6be844SDan Williams 3666568b08bSDan Williams dax_dev->ops = ops; 3677b6be844SDan Williams dax_dev->private = private; 3687b6be844SDan Williams return dax_dev; 3697b6be844SDan Williams 37072058005SDan Williams err_dev: 3717b6be844SDan Williams ida_simple_remove(&dax_minor_ida, minor); 3724e4ced93SVivek Goyal return ERR_PTR(-ENOMEM); 3737b6be844SDan Williams } 3747b6be844SDan Williams EXPORT_SYMBOL_GPL(alloc_dax); 3757b6be844SDan Williams 3767b6be844SDan Williams void put_dax(struct dax_device *dax_dev) 3777b6be844SDan Williams { 3787b6be844SDan Williams if (!dax_dev) 3797b6be844SDan Williams return; 3807b6be844SDan Williams iput(&dax_dev->inode); 3817b6be844SDan Williams } 3827b6be844SDan Williams EXPORT_SYMBOL_GPL(put_dax); 3837b6be844SDan Williams 3847b6be844SDan Williams /** 3857b6be844SDan Williams * inode_dax: convert a public inode into its dax_dev 3867b6be844SDan Williams * @inode: An inode with i_cdev pointing to a dax_dev 3877b6be844SDan Williams * 3887b6be844SDan Williams * Note this is not equivalent to to_dax_dev() which is for private 3897b6be844SDan Williams * internal use where we know the inode filesystem type == dax_fs_type. 3907b6be844SDan Williams */ 3917b6be844SDan Williams struct dax_device *inode_dax(struct inode *inode) 3927b6be844SDan Williams { 3937b6be844SDan Williams struct cdev *cdev = inode->i_cdev; 3947b6be844SDan Williams 3957b6be844SDan Williams return container_of(cdev, struct dax_device, cdev); 3967b6be844SDan Williams } 3977b6be844SDan Williams EXPORT_SYMBOL_GPL(inode_dax); 3987b6be844SDan Williams 3997b6be844SDan Williams struct inode *dax_inode(struct dax_device *dax_dev) 4007b6be844SDan Williams { 4017b6be844SDan Williams return &dax_dev->inode; 4027b6be844SDan Williams } 4037b6be844SDan Williams EXPORT_SYMBOL_GPL(dax_inode); 4047b6be844SDan Williams 4057b6be844SDan Williams void *dax_get_private(struct dax_device *dax_dev) 4067b6be844SDan Williams { 4079567da0bSDan Williams if (!test_bit(DAXDEV_ALIVE, &dax_dev->flags)) 4089567da0bSDan Williams return NULL; 4097b6be844SDan Williams return dax_dev->private; 4107b6be844SDan Williams } 4117b6be844SDan Williams EXPORT_SYMBOL_GPL(dax_get_private); 4127b6be844SDan Williams 4137b6be844SDan Williams static void init_once(void *_dax_dev) 4147b6be844SDan Williams { 4157b6be844SDan Williams struct dax_device *dax_dev = _dax_dev; 4167b6be844SDan Williams struct inode *inode = &dax_dev->inode; 4177b6be844SDan Williams 418b9d39d17SDan Williams memset(dax_dev, 0, sizeof(*dax_dev)); 4197b6be844SDan Williams inode_init_once(inode); 4207b6be844SDan Williams } 4217b6be844SDan Williams 4229567da0bSDan Williams static int dax_fs_init(void) 4237b6be844SDan Williams { 4247b6be844SDan Williams int rc; 4257b6be844SDan Williams 4267b6be844SDan Williams dax_cache = kmem_cache_create("dax_cache", sizeof(struct dax_device), 0, 4277b6be844SDan Williams (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 4287b6be844SDan Williams SLAB_MEM_SPREAD|SLAB_ACCOUNT), 4297b6be844SDan Williams init_once); 4307b6be844SDan Williams if (!dax_cache) 4317b6be844SDan Williams return -ENOMEM; 4327b6be844SDan Williams 4337b6be844SDan Williams dax_mnt = kern_mount(&dax_fs_type); 4347b6be844SDan Williams if (IS_ERR(dax_mnt)) { 4357b6be844SDan Williams rc = PTR_ERR(dax_mnt); 4367b6be844SDan Williams goto err_mount; 4377b6be844SDan Williams } 4387b6be844SDan Williams dax_superblock = dax_mnt->mnt_sb; 4397b6be844SDan Williams 4407b6be844SDan Williams return 0; 4417b6be844SDan Williams 4427b6be844SDan Williams err_mount: 4437b6be844SDan Williams kmem_cache_destroy(dax_cache); 4447b6be844SDan Williams 4457b6be844SDan Williams return rc; 4467b6be844SDan Williams } 4477b6be844SDan Williams 4489567da0bSDan Williams static void dax_fs_exit(void) 4497b6be844SDan Williams { 4507b6be844SDan Williams kern_unmount(dax_mnt); 4517b6be844SDan Williams kmem_cache_destroy(dax_cache); 4527b6be844SDan Williams } 4537b6be844SDan Williams 4549567da0bSDan Williams static int __init dax_core_init(void) 4557b6be844SDan Williams { 4567b6be844SDan Williams int rc; 4577b6be844SDan Williams 4589567da0bSDan Williams rc = dax_fs_init(); 4597b6be844SDan Williams if (rc) 4607b6be844SDan Williams return rc; 4617b6be844SDan Williams 462cf1e2289SDan Williams rc = alloc_chrdev_region(&dax_devt, 0, MINORMASK+1, "dax"); 4637b6be844SDan Williams if (rc) 4649567da0bSDan Williams goto err_chrdev; 4659567da0bSDan Williams 4669567da0bSDan Williams rc = dax_bus_init(); 4679567da0bSDan Williams if (rc) 4689567da0bSDan Williams goto err_bus; 4699567da0bSDan Williams return 0; 4709567da0bSDan Williams 4719567da0bSDan Williams err_bus: 4729567da0bSDan Williams unregister_chrdev_region(dax_devt, MINORMASK+1); 4739567da0bSDan Williams err_chrdev: 4749567da0bSDan Williams dax_fs_exit(); 4759567da0bSDan Williams return 0; 4767b6be844SDan Williams } 4777b6be844SDan Williams 4789567da0bSDan Williams static void __exit dax_core_exit(void) 4797b6be844SDan Williams { 4801aa57431SWang Hai dax_bus_exit(); 481cf1e2289SDan Williams unregister_chrdev_region(dax_devt, MINORMASK+1); 4827b6be844SDan Williams ida_destroy(&dax_minor_ida); 4839567da0bSDan Williams dax_fs_exit(); 4847b6be844SDan Williams } 4857b6be844SDan Williams 4867b6be844SDan Williams MODULE_AUTHOR("Intel Corporation"); 4877b6be844SDan Williams MODULE_LICENSE("GPL v2"); 4889567da0bSDan Williams subsys_initcall(dax_core_init); 4899567da0bSDan Williams module_exit(dax_core_exit); 490