02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 1) // SPDX-License-Identifier: GPL-2.0-only
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 2) #include <linux/slab.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 3) #include <linux/stat.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 4) #include <linux/sched/xacct.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 5) #include <linux/fcntl.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 6) #include <linux/file.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 7) #include <linux/uio.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 8) #include <linux/fsnotify.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 9) #include <linux/security.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 10) #include <linux/export.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 11) #include <linux/syscalls.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 12) #include <linux/pagemap.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 13) #include <linux/splice.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 14) #include <linux/compat.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 15) #include <linux/mount.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 16) #include <linux/fs.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 17) #include "internal.h"
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 18)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 19) #include <linux/uaccess.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 20) #include <asm/unistd.h>
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 21)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 22) /*
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 23) * Performs necessary checks before doing a clone.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 24) *
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 25) * Can adjust amount of bytes to clone via @req_count argument.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 26) * Returns appropriate error code that caller should return or
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 27) * zero in case the clone should be allowed.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 28) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 29) static int generic_remap_checks(struct file *file_in, loff_t pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 30) struct file *file_out, loff_t pos_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 31) loff_t *req_count, unsigned int remap_flags)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 32) {
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 33) struct inode *inode_in = file_in->f_mapping->host;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 34) struct inode *inode_out = file_out->f_mapping->host;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 35) uint64_t count = *req_count;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 36) uint64_t bcount;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 37) loff_t size_in, size_out;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 38) loff_t bs = inode_out->i_sb->s_blocksize;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 39) int ret;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 40)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 41) /* The start of both ranges must be aligned to an fs block. */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 42) if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs))
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 43) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 44)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 45) /* Ensure offsets don't wrap. */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 46) if (pos_in + count < pos_in || pos_out + count < pos_out)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 47) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 48)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 49) size_in = i_size_read(inode_in);
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 50) size_out = i_size_read(inode_out);
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 51)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 52) /* Dedupe requires both ranges to be within EOF. */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 53) if ((remap_flags & REMAP_FILE_DEDUP) &&
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 54) (pos_in >= size_in || pos_in + count > size_in ||
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 55) pos_out >= size_out || pos_out + count > size_out))
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 56) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 57)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 58) /* Ensure the infile range is within the infile. */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 59) if (pos_in >= size_in)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 60) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 61) count = min(count, size_in - (uint64_t)pos_in);
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 62)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 63) ret = generic_write_check_limits(file_out, pos_out, &count);
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 64) if (ret)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 65) return ret;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 66)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 67) /*
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 68) * If the user wanted us to link to the infile's EOF, round up to the
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 69) * next block boundary for this check.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 70) *
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 71) * Otherwise, make sure the count is also block-aligned, having
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 72) * already confirmed the starting offsets' block alignment.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 73) */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 74) if (pos_in + count == size_in) {
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 75) bcount = ALIGN(size_in, bs) - pos_in;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 76) } else {
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 77) if (!IS_ALIGNED(count, bs))
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 78) count = ALIGN_DOWN(count, bs);
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 79) bcount = count;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 80) }
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 81)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 82) /* Don't allow overlapped cloning within the same file. */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 83) if (inode_in == inode_out &&
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 84) pos_out + bcount > pos_in &&
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 85) pos_out < pos_in + bcount)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 86) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 87)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 88) /*
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 89) * We shortened the request but the caller can't deal with that, so
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 90) * bounce the request back to userspace.
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 91) */
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 92) if (*req_count != count && !(remap_flags & REMAP_FILE_CAN_SHORTEN))
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 93) return -EINVAL;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 94)
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 95) *req_count = count;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 96) return 0;
02e83f46ebfaf (Darrick J. Wong 2020-10-14 16:47:08 -0700 97) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 98)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 99) static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 100) bool write)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 101) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 102) struct inode *inode = file_inode(file);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 103)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 104) if (unlikely(pos < 0 || len < 0))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 105) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 106)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 107) if (unlikely((loff_t) (pos + len) < 0))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 108) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 109)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 110) if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 111) loff_t end = len ? pos + len - 1 : OFFSET_MAX;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 112) int retval;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 113)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 114) retval = locks_mandatory_area(inode, file, pos, end,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 115) write ? F_WRLCK : F_RDLCK);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 116) if (retval < 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 117) return retval;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 118) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 119)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 120) return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 121) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 122)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 123) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 124) * Ensure that we don't remap a partial EOF block in the middle of something
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 125) * else. Assume that the offsets have already been checked for block
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 126) * alignment.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 127) *
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 128) * For clone we only link a partial EOF block above or at the destination file's
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 129) * EOF. For deduplication we accept a partial EOF block only if it ends at the
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 130) * destination file's EOF (can not link it into the middle of a file).
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 131) *
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 132) * Shorten the request if possible.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 133) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 134) static int generic_remap_check_len(struct inode *inode_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 135) struct inode *inode_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 136) loff_t pos_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 137) loff_t *len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 138) unsigned int remap_flags)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 139) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 140) u64 blkmask = i_blocksize(inode_in) - 1;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 141) loff_t new_len = *len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 142)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 143) if ((*len & blkmask) == 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 144) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 145)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 146) if (pos_out + *len < i_size_read(inode_out))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 147) new_len &= ~blkmask;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 148)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 149) if (new_len == *len)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 150) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 151)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 152) if (remap_flags & REMAP_FILE_CAN_SHORTEN) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 153) *len = new_len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 154) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 155) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 156)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 157) return (remap_flags & REMAP_FILE_DEDUP) ? -EBADE : -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 158) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 159)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 160) /* Read a page's worth of file data into the page cache. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 161) static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 162) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 163) struct page *page;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 164)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 165) page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 166) if (IS_ERR(page))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 167) return page;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 168) if (!PageUptodate(page)) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 169) put_page(page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 170) return ERR_PTR(-EIO);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 171) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 172) return page;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 173) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 174)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 175) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 176) * Lock two pages, ensuring that we lock in offset order if the pages are from
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 177) * the same file.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 178) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 179) static void vfs_lock_two_pages(struct page *page1, struct page *page2)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 180) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 181) /* Always lock in order of increasing index. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 182) if (page1->index > page2->index)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 183) swap(page1, page2);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 184)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 185) lock_page(page1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 186) if (page1 != page2)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 187) lock_page(page2);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 188) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 189)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 190) /* Unlock two pages, being careful not to unlock the same page twice. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 191) static void vfs_unlock_two_pages(struct page *page1, struct page *page2)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 192) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 193) unlock_page(page1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 194) if (page1 != page2)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 195) unlock_page(page2);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 196) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 197)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 198) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 199) * Compare extents of two files to see if they are the same.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 200) * Caller must have locked both inodes to prevent write races.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 201) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 202) static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 203) struct inode *dest, loff_t destoff,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 204) loff_t len, bool *is_same)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 205) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 206) loff_t src_poff;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 207) loff_t dest_poff;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 208) void *src_addr;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 209) void *dest_addr;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 210) struct page *src_page;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 211) struct page *dest_page;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 212) loff_t cmp_len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 213) bool same;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 214) int error;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 215)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 216) error = -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 217) same = true;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 218) while (len) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 219) src_poff = srcoff & (PAGE_SIZE - 1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 220) dest_poff = destoff & (PAGE_SIZE - 1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 221) cmp_len = min(PAGE_SIZE - src_poff,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 222) PAGE_SIZE - dest_poff);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 223) cmp_len = min(cmp_len, len);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 224) if (cmp_len <= 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 225) goto out_error;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 226)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 227) src_page = vfs_dedupe_get_page(src, srcoff);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 228) if (IS_ERR(src_page)) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 229) error = PTR_ERR(src_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 230) goto out_error;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 231) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 232) dest_page = vfs_dedupe_get_page(dest, destoff);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 233) if (IS_ERR(dest_page)) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 234) error = PTR_ERR(dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 235) put_page(src_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 236) goto out_error;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 237) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 238)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 239) vfs_lock_two_pages(src_page, dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 240)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 241) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 242) * Now that we've locked both pages, make sure they're still
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 243) * mapped to the file data we're interested in. If not,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 244) * someone is invalidating pages on us and we lose.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 245) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 246) if (!PageUptodate(src_page) || !PageUptodate(dest_page) ||
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 247) src_page->mapping != src->i_mapping ||
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 248) dest_page->mapping != dest->i_mapping) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 249) same = false;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 250) goto unlock;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 251) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 252)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 253) src_addr = kmap_atomic(src_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 254) dest_addr = kmap_atomic(dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 255)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 256) flush_dcache_page(src_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 257) flush_dcache_page(dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 258)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 259) if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 260) same = false;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 261)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 262) kunmap_atomic(dest_addr);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 263) kunmap_atomic(src_addr);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 264) unlock:
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 265) vfs_unlock_two_pages(src_page, dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 266) put_page(dest_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 267) put_page(src_page);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 268)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 269) if (!same)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 270) break;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 271)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 272) srcoff += cmp_len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 273) destoff += cmp_len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 274) len -= cmp_len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 275) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 276)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 277) *is_same = same;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 278) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 279)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 280) out_error:
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 281) return error;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 282) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 283)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 284) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 285) * Check that the two inodes are eligible for cloning, the ranges make
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 286) * sense, and then flush all dirty data. Caller must ensure that the
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 287) * inodes have been locked against any other modifications.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 288) *
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 289) * If there's an error, then the usual negative error code is returned.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 290) * Otherwise returns 0 with *len set to the request length.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 291) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 292) int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 293) struct file *file_out, loff_t pos_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 294) loff_t *len, unsigned int remap_flags)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 295) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 296) struct inode *inode_in = file_inode(file_in);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 297) struct inode *inode_out = file_inode(file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 298) bool same_inode = (inode_in == inode_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 299) int ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 300)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 301) /* Don't touch certain kinds of inodes */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 302) if (IS_IMMUTABLE(inode_out))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 303) return -EPERM;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 304)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 305) if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 306) return -ETXTBSY;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 307)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 308) /* Don't reflink dirs, pipes, sockets... */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 309) if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 310) return -EISDIR;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 311) if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 312) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 313)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 314) /* Zero length dedupe exits immediately; reflink goes to EOF. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 315) if (*len == 0) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 316) loff_t isize = i_size_read(inode_in);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 317)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 318) if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 319) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 320) if (pos_in > isize)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 321) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 322) *len = isize - pos_in;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 323) if (*len == 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 324) return 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 325) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 326)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 327) /* Check that we don't violate system file offset limits. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 328) ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 329) remap_flags);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 330) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 331) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 332)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 333) /* Wait for the completion of any pending IOs on both files */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 334) inode_dio_wait(inode_in);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 335) if (!same_inode)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 336) inode_dio_wait(inode_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 337)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 338) ret = filemap_write_and_wait_range(inode_in->i_mapping,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 339) pos_in, pos_in + *len - 1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 340) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 341) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 342)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 343) ret = filemap_write_and_wait_range(inode_out->i_mapping,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 344) pos_out, pos_out + *len - 1);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 345) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 346) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 347)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 348) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 349) * Check that the extents are the same.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 350) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 351) if (remap_flags & REMAP_FILE_DEDUP) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 352) bool is_same = false;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 353)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 354) ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 355) inode_out, pos_out, *len, &is_same);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 356) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 357) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 358) if (!is_same)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 359) return -EBADE;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 360) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 361)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 362) ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 363) remap_flags);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 364) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 365) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 366)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 367) /* If can't alter the file contents, we're done. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 368) if (!(remap_flags & REMAP_FILE_DEDUP))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 369) ret = file_modified(file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 370)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 371) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 372) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 373) EXPORT_SYMBOL(generic_remap_file_range_prep);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 374)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 375) loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 376) struct file *file_out, loff_t pos_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 377) loff_t len, unsigned int remap_flags)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 378) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 379) loff_t ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 380)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 381) WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 382)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 383) /*
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 384) * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 385) * the same mount. Practically, they only need to be on the same file
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 386) * system.
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 387) */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 388) if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 389) return -EXDEV;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 390)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 391) ret = generic_file_rw_checks(file_in, file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 392) if (ret < 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 393) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 394)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 395) if (!file_in->f_op->remap_file_range)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 396) return -EOPNOTSUPP;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 397)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 398) ret = remap_verify_area(file_in, pos_in, len, false);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 399) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 400) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 401)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 402) ret = remap_verify_area(file_out, pos_out, len, true);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 403) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 404) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 405)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 406) ret = file_in->f_op->remap_file_range(file_in, pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 407) file_out, pos_out, len, remap_flags);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 408) if (ret < 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 409) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 410)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 411) fsnotify_access(file_in);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 412) fsnotify_modify(file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 413) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 414) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 415) EXPORT_SYMBOL(do_clone_file_range);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 416)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 417) loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 418) struct file *file_out, loff_t pos_out,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 419) loff_t len, unsigned int remap_flags)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 420) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 421) loff_t ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 422)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 423) file_start_write(file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 424) ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 425) remap_flags);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 426) file_end_write(file_out);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 427)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 428) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 429) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 430) EXPORT_SYMBOL(vfs_clone_file_range);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 431)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 432) /* Check whether we are allowed to dedupe the destination file */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 433) static bool allow_file_dedupe(struct file *file)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 434) {
0f5d220b42fba (Christian Brauner 2021-01-21 14:19:40 +0100 435) struct user_namespace *mnt_userns = file_mnt_user_ns(file);
0f5d220b42fba (Christian Brauner 2021-01-21 14:19:40 +0100 436) struct inode *inode = file_inode(file);
0f5d220b42fba (Christian Brauner 2021-01-21 14:19:40 +0100 437)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 438) if (capable(CAP_SYS_ADMIN))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 439) return true;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 440) if (file->f_mode & FMODE_WRITE)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 441) return true;
0f5d220b42fba (Christian Brauner 2021-01-21 14:19:40 +0100 442) if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 443) return true;
0f5d220b42fba (Christian Brauner 2021-01-21 14:19:40 +0100 444) if (!inode_permission(mnt_userns, inode, MAY_WRITE))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 445) return true;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 446) return false;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 447) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 448)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 449) loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 450) struct file *dst_file, loff_t dst_pos,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 451) loff_t len, unsigned int remap_flags)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 452) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 453) loff_t ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 454)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 455) WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP |
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 456) REMAP_FILE_CAN_SHORTEN));
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 457)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 458) ret = mnt_want_write_file(dst_file);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 459) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 460) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 461)
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 462) /*
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 463) * This is redundant if called from vfs_dedupe_file_range(), but other
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 464) * callers need it and it's not performance sesitive...
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 465) */
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 466) ret = remap_verify_area(src_file, src_pos, len, false);
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 467) if (ret)
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 468) goto out_drop_write;
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 469)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 470) ret = remap_verify_area(dst_file, dst_pos, len, true);
3078d85c9a109 (Miklos Szeredi 2020-12-14 15:26:13 +0100 471) if (ret)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 472) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 473)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 474) ret = -EPERM;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 475) if (!allow_file_dedupe(dst_file))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 476) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 477)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 478) ret = -EXDEV;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 479) if (src_file->f_path.mnt != dst_file->f_path.mnt)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 480) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 481)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 482) ret = -EISDIR;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 483) if (S_ISDIR(file_inode(dst_file)->i_mode))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 484) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 485)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 486) ret = -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 487) if (!dst_file->f_op->remap_file_range)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 488) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 489)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 490) if (len == 0) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 491) ret = 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 492) goto out_drop_write;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 493) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 494)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 495) ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 496) dst_pos, len, remap_flags | REMAP_FILE_DEDUP);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 497) out_drop_write:
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 498) mnt_drop_write_file(dst_file);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 499)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 500) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 501) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 502) EXPORT_SYMBOL(vfs_dedupe_file_range_one);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 503)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 504) int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 505) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 506) struct file_dedupe_range_info *info;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 507) struct inode *src = file_inode(file);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 508) u64 off;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 509) u64 len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 510) int i;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 511) int ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 512) u16 count = same->dest_count;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 513) loff_t deduped;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 514)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 515) if (!(file->f_mode & FMODE_READ))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 516) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 517)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 518) if (same->reserved1 || same->reserved2)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 519) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 520)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 521) off = same->src_offset;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 522) len = same->src_length;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 523)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 524) if (S_ISDIR(src->i_mode))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 525) return -EISDIR;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 526)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 527) if (!S_ISREG(src->i_mode))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 528) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 529)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 530) if (!file->f_op->remap_file_range)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 531) return -EOPNOTSUPP;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 532)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 533) ret = remap_verify_area(file, off, len, false);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 534) if (ret < 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 535) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 536) ret = 0;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 537)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 538) if (off + len > i_size_read(src))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 539) return -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 540)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 541) /* Arbitrary 1G limit on a single dedupe request, can be raised. */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 542) len = min_t(u64, len, 1 << 30);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 543)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 544) /* pre-format output fields to sane values */
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 545) for (i = 0; i < count; i++) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 546) same->info[i].bytes_deduped = 0ULL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 547) same->info[i].status = FILE_DEDUPE_RANGE_SAME;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 548) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 549)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 550) for (i = 0, info = same->info; i < count; i++, info++) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 551) struct fd dst_fd = fdget(info->dest_fd);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 552) struct file *dst_file = dst_fd.file;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 553)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 554) if (!dst_file) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 555) info->status = -EBADF;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 556) goto next_loop;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 557) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 558)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 559) if (info->reserved) {
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 560) info->status = -EINVAL;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 561) goto next_fdput;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 562) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 563)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 564) deduped = vfs_dedupe_file_range_one(file, off, dst_file,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 565) info->dest_offset, len,
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 566) REMAP_FILE_CAN_SHORTEN);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 567) if (deduped == -EBADE)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 568) info->status = FILE_DEDUPE_RANGE_DIFFERS;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 569) else if (deduped < 0)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 570) info->status = deduped;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 571) else
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 572) info->bytes_deduped = len;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 573)
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 574) next_fdput:
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 575) fdput(dst_fd);
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 576) next_loop:
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 577) if (fatal_signal_pending(current))
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 578) break;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 579) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 580) return ret;
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 581) }
1b2c54d63cde7 (Darrick J. Wong 2020-10-14 16:38:47 -0700 582) EXPORT_SYMBOL(vfs_dedupe_file_range);
VisionFive2 Linux kernel
StarFive Tech Linux Kernel for VisionFive (JH7110) boards (mirror)
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