c0b2462597
Ext4 needs to pass through error from its iomap handler to the page fault handler so that it can properly detect ENOSPC and force transaction commit and retry the fault (and block allocation). Add argument to dax_iomap_fault() for passing such error. Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
128 lines
3.7 KiB
C
128 lines
3.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_DAX_H
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#define _LINUX_DAX_H
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/radix-tree.h>
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#include <asm/pgtable.h>
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struct iomap_ops;
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struct dax_device;
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struct dax_operations {
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/*
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* direct_access: translate a device-relative
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* logical-page-offset into an absolute physical pfn. Return the
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* number of pages available for DAX at that pfn.
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*/
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long (*direct_access)(struct dax_device *, pgoff_t, long,
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void **, pfn_t *);
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/* copy_from_iter: required operation for fs-dax direct-i/o */
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size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
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struct iov_iter *);
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};
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extern struct attribute_group dax_attribute_group;
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#if IS_ENABLED(CONFIG_DAX)
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struct dax_device *dax_get_by_host(const char *host);
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void put_dax(struct dax_device *dax_dev);
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#else
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static inline struct dax_device *dax_get_by_host(const char *host)
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{
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return NULL;
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}
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static inline void put_dax(struct dax_device *dax_dev)
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{
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}
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#endif
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int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
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#if IS_ENABLED(CONFIG_FS_DAX)
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int __bdev_dax_supported(struct super_block *sb, int blocksize);
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static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
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{
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return __bdev_dax_supported(sb, blocksize);
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}
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static inline struct dax_device *fs_dax_get_by_host(const char *host)
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{
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return dax_get_by_host(host);
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}
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static inline void fs_put_dax(struct dax_device *dax_dev)
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{
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put_dax(dax_dev);
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}
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struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
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#else
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static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
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{
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return -EOPNOTSUPP;
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}
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static inline struct dax_device *fs_dax_get_by_host(const char *host)
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{
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return NULL;
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}
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static inline void fs_put_dax(struct dax_device *dax_dev)
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{
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}
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static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
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{
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return NULL;
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}
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#endif
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int dax_read_lock(void);
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void dax_read_unlock(int id);
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struct dax_device *alloc_dax(void *private, const char *host,
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const struct dax_operations *ops);
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bool dax_alive(struct dax_device *dax_dev);
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void kill_dax(struct dax_device *dax_dev);
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void *dax_get_private(struct dax_device *dax_dev);
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long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
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void **kaddr, pfn_t *pfn);
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size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
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size_t bytes, struct iov_iter *i);
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void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
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void dax_write_cache(struct dax_device *dax_dev, bool wc);
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bool dax_write_cache_enabled(struct dax_device *dax_dev);
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ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
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const struct iomap_ops *ops);
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int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
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pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
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int dax_finish_sync_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
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pfn_t pfn);
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int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
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int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
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pgoff_t index);
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#ifdef CONFIG_FS_DAX
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int __dax_zero_page_range(struct block_device *bdev,
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struct dax_device *dax_dev, sector_t sector,
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unsigned int offset, unsigned int length);
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#else
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static inline int __dax_zero_page_range(struct block_device *bdev,
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struct dax_device *dax_dev, sector_t sector,
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unsigned int offset, unsigned int length)
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{
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return -ENXIO;
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}
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#endif
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static inline bool dax_mapping(struct address_space *mapping)
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{
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return mapping->host && IS_DAX(mapping->host);
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}
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struct writeback_control;
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int dax_writeback_mapping_range(struct address_space *mapping,
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struct block_device *bdev, struct writeback_control *wbc);
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#endif
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