VisionFive2 Linux kernel

56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   1) // SPDX-License-Identifier: GPL-2.0
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   2) /*
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   3)  * Copyright (C) 2017 Red Hat, Inc.
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   4)  * Copyright (c) 2018 Christoph Hellwig.
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   5)  */
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   6) #include <linux/module.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   7) #include <linux/compiler.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   8) #include <linux/fs.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700   9) #include <linux/iomap.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  10) #include <linux/pagemap.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  11) #include <linux/pagevec.h>
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  12) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  13) static loff_t
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  14) iomap_seek_hole_actor(struct inode *inode, loff_t start, loff_t length,
c039b99792726 (Goldwyn Rodrigues       2019-10-18 16:44:10 -0700  15) 		      void *data, struct iomap *iomap, struct iomap *srcmap)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  16) {
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  17) 	loff_t offset = start;
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  18) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  19) 	switch (iomap->type) {
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  20) 	case IOMAP_UNWRITTEN:
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  21) 		offset = mapping_seek_hole_data(inode->i_mapping, start,
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  22) 				start + length, SEEK_HOLE);
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  23) 		if (offset == start + length)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  24) 			return length;
df561f6688fef (Gustavo A. R. Silva     2020-08-23 17:36:59 -0500  25) 		fallthrough;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  26) 	case IOMAP_HOLE:
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  27) 		*(loff_t *)data = offset;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  28) 		return 0;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  29) 	default:
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  30) 		return length;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  31) 	}
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  32) }
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  33) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  34) loff_t
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  35) iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  36) {
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  37) 	loff_t size = i_size_read(inode);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  38) 	loff_t ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  39) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  40) 	/* Nothing to be found before or beyond the end of the file. */
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  41) 	if (offset < 0 || offset >= size)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  42) 		return -ENXIO;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  43) 
0ad0e62e74cec (Christoph Hellwig       2021-07-15 09:58:04 -0700  44) 	while (offset < size) {
0ad0e62e74cec (Christoph Hellwig       2021-07-15 09:58:04 -0700  45) 		ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT,
0ad0e62e74cec (Christoph Hellwig       2021-07-15 09:58:04 -0700  46) 				  ops, &offset, iomap_seek_hole_actor);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  47) 		if (ret < 0)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  48) 			return ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  49) 		if (ret == 0)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  50) 			break;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  51) 		offset += ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  52) 	}
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  53) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  54) 	return offset;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  55) }
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  56) EXPORT_SYMBOL_GPL(iomap_seek_hole);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  57) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  58) static loff_t
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  59) iomap_seek_data_actor(struct inode *inode, loff_t start, loff_t length,
c039b99792726 (Goldwyn Rodrigues       2019-10-18 16:44:10 -0700  60) 		      void *data, struct iomap *iomap, struct iomap *srcmap)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  61) {
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  62) 	loff_t offset = start;
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  63) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  64) 	switch (iomap->type) {
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  65) 	case IOMAP_HOLE:
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  66) 		return length;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  67) 	case IOMAP_UNWRITTEN:
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  68) 		offset = mapping_seek_hole_data(inode->i_mapping, start,
54fa39ac2e00b (Matthew Wilcox (Oracle) 2021-02-25 17:15:52 -0800  69) 				start + length, SEEK_DATA);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  70) 		if (offset < 0)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  71) 			return length;
df561f6688fef (Gustavo A. R. Silva     2020-08-23 17:36:59 -0500  72) 		fallthrough;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  73) 	default:
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  74) 		*(loff_t *)data = offset;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  75) 		return 0;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  76) 	}
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  77) }
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  78) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  79) loff_t
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  80) iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  81) {
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  82) 	loff_t size = i_size_read(inode);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  83) 	loff_t ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  84) 
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  85) 	/* Nothing to be found before or beyond the end of the file. */
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  86) 	if (offset < 0 || offset >= size)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  87) 		return -ENXIO;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  88) 
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700  89) 	while (offset < size) {
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700  90) 		ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT,
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700  91) 				  ops, &offset, iomap_seek_data_actor);
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  92) 		if (ret < 0)
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  93) 			return ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  94) 		if (ret == 0)
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700  95) 			return offset;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  96) 		offset += ret;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  97) 	}
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700  98) 
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700  99) 	/* We've reached the end of the file without finding data */
521168b44c085 (Christoph Hellwig       2021-07-15 09:58:04 -0700 100) 	return -ENXIO;
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700 101) }
56a178981d470 (Darrick J. Wong         2019-07-15 08:50:58 -0700 102) EXPORT_SYMBOL_GPL(iomap_seek_data);