Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Copyright (C) 2018 Oracle.  All Rights Reserved.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Author: Darrick J. Wong <darrick.wong@oracle.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include <linux/compiler.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/iomap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/swap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) /* Swapfile activation */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) struct iomap_swapfile_info {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) 	struct iomap iomap;		/* accumulated iomap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 	struct swap_info_struct *sis;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 	uint64_t lowest_ppage;		/* lowest physical addr seen (pages) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 	uint64_t highest_ppage;		/* highest physical addr seen (pages) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 	unsigned long nr_pages;		/* number of pages collected */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 	int nr_extents;			/* extent count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24)  * Collect physical extents for this swap file.  Physical extents reported to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25)  * the swap code must be trimmed to align to a page boundary.  The logical
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26)  * offset within the file is irrelevant since the swapfile code maps logical
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27)  * page numbers of the swap device to the physical page-aligned extents.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	struct iomap *iomap = &isi->iomap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	unsigned long nr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	unsigned long max_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	uint64_t first_ppage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	uint64_t first_ppage_reported;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	uint64_t next_ppage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	int error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	if (unlikely(isi->nr_pages >= isi->sis->max))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	max_pages = isi->sis->max - isi->nr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	 * Round the start up and the end down so that the physical
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	 * extent aligns to a page boundary.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	first_ppage = ALIGN(iomap->addr, PAGE_SIZE) >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	next_ppage = ALIGN_DOWN(iomap->addr + iomap->length, PAGE_SIZE) >>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 			PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	/* Skip too-short physical extents. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	if (first_ppage >= next_ppage)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	nr_pages = next_ppage - first_ppage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	nr_pages = min(nr_pages, max_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	 * Calculate how much swap space we're adding; the first page contains
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	 * the swap header and doesn't count.  The mm still wants that first
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	 * page fed to add_swap_extent, however.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	first_ppage_reported = first_ppage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	if (iomap->offset == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 		first_ppage_reported++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	if (isi->lowest_ppage > first_ppage_reported)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 		isi->lowest_ppage = first_ppage_reported;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	if (isi->highest_ppage < (next_ppage - 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		isi->highest_ppage = next_ppage - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	/* Add extent, set up for the next call. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	error = add_swap_extent(isi->sis, isi->nr_pages, nr_pages, first_ppage);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	if (error < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	isi->nr_extents += error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	isi->nr_pages += nr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80)  * Accumulate iomaps for this swap file.  We have to accumulate iomaps because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81)  * swap only cares about contiguous page-aligned physical extents and makes no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82)  * distinction between written and unwritten extents.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 		loff_t count, void *data, struct iomap *iomap,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 		struct iomap *srcmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	struct iomap_swapfile_info *isi = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	int error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	switch (iomap->type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	case IOMAP_MAPPED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	case IOMAP_UNWRITTEN:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 		/* Only real or unwritten extents. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	case IOMAP_INLINE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		/* No inline data. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		pr_err("swapon: file is inline\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		pr_err("swapon: file has unallocated extents\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	/* No uncommitted metadata or shared blocks. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	if (iomap->flags & IOMAP_F_DIRTY) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		pr_err("swapon: file is not committed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	if (iomap->flags & IOMAP_F_SHARED) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 		pr_err("swapon: file has shared extents\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	/* Only one bdev per swap file. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	if (iomap->bdev != isi->sis->bdev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 		pr_err("swapon: file is on multiple devices\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	if (isi->iomap.length == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 		/* No accumulated extent, so just store it. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 		memcpy(&isi->iomap, iomap, sizeof(isi->iomap));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	} else if (isi->iomap.addr + isi->iomap.length == iomap->addr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 		/* Append this to the accumulated extent. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 		isi->iomap.length += iomap->length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 		/* Otherwise, add the retained iomap and store this one. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		error = iomap_swapfile_add_extent(isi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 		if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 			return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 		memcpy(&isi->iomap, iomap, sizeof(isi->iomap));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)  * Iterate a swap file's iomaps to construct physical extents that can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)  * passed to the swapfile subsystem.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) int iomap_swapfile_activate(struct swap_info_struct *sis,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 		struct file *swap_file, sector_t *pagespan,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		const struct iomap_ops *ops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	struct iomap_swapfile_info isi = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 		.sis = sis,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 		.lowest_ppage = (sector_t)-1ULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	struct address_space *mapping = swap_file->f_mapping;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	struct inode *inode = mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	loff_t pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	loff_t len = ALIGN_DOWN(i_size_read(inode), PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	loff_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	 * Persist all file mapping metadata so that we won't have any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	 * IOMAP_F_DIRTY iomaps.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	ret = vfs_fsync(swap_file, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 		return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	while (len > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 		ret = iomap_apply(inode, pos, len, IOMAP_REPORT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 				ops, &isi, iomap_swapfile_activate_actor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 		if (ret <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 			return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 		pos += ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 		len -= ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	if (isi.iomap.length) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 		ret = iomap_swapfile_add_extent(&isi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 			return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	 * If this swapfile doesn't contain even a single page-aligned
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	 * contiguous range of blocks, reject this useless swapfile to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	 * prevent confusion later on.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	if (isi.nr_pages == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		pr_warn("swapon: Cannot find a single usable page in file.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	*pagespan = 1 + isi.highest_ppage - isi.lowest_ppage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	sis->max = isi.nr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	sis->pages = isi.nr_pages - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	sis->highest_bit = isi.nr_pages - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	return isi.nr_extents;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) EXPORT_SYMBOL_GPL(iomap_swapfile_activate);