/* * fs/bfs/file.c * BFS file operations. * Copyright (C) 1999,2000 Tigran Aivazian * * Make the file block allocation algorithm understand the size * of the underlying block device. * Copyright (C) 2007 Dmitri Vorobiev * */ #include #include #include "bfs.h" #undef DEBUG #ifdef DEBUG #define dprintf(x...) printf(x) #else #define dprintf(x...) #endif const struct file_operations bfs_file_operations = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .splice_read = generic_file_splice_read, }; static int bfs_move_block(unsigned long from, unsigned long to, struct super_block *sb) { struct buffer_head *bh, *new; bh = sb_bread(sb, from); if (!bh) return -EIO; new = sb_getblk(sb, to); memcpy(new->b_data, bh->b_data, bh->b_size); mark_buffer_dirty(new); bforget(bh); brelse(new); return 0; } static int bfs_move_blocks(struct super_block *sb, unsigned long start, unsigned long end, unsigned long where) { unsigned long i; dprintf("%08lx-%08lx->%08lx\n", start, end, where); for (i = start; i <= end; i++) if(bfs_move_block(i, where + i, sb)) { dprintf("failed to move block %08lx -> %08lx\n", i, where + i); return -EIO; } return 0; } static int bfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create) { unsigned long phys; int err; struct super_block *sb = inode->i_sb; struct bfs_sb_info *info = BFS_SB(sb); struct bfs_inode_info *bi = BFS_I(inode); phys = bi->i_sblock + block; if (!create) { if (phys <= bi->i_eblock) { dprintf("c=%d, b=%08lx, phys=%09lx (granted)\n", create, (unsigned long)block, phys); map_bh(bh_result, sb, phys); } return 0; } /* * If the file is not empty and the requested block is within the * range of blocks allocated for this file, we can grant it. */ if (bi->i_sblock && (phys <= bi->i_eblock)) { dprintf("c=%d, b=%08lx, phys=%08lx (interim block granted)\n", create, (unsigned long)block, phys); map_bh(bh_result, sb, phys); return 0; } /* The file will be extended, so let's see if there is enough space. */ if (phys >= info->si_blocks) return -ENOSPC; /* The rest has to be protected against itself. */ mutex_lock(&info->bfs_lock); /* * If the last data block for this file is the last allocated * block, we can extend the file trivially, without moving it * anywhere. */ if (bi->i_eblock == info->si_lf_eblk) { dprintf("c=%d, b=%08lx, phys=%08lx (simple extension)\n", create, (unsigned long)block, phys); map_bh(bh_result, sb, phys); info->si_freeb -= phys - bi->i_eblock; info->si_lf_eblk = bi->i_eblock = phys; mark_inode_dirty(inode); err = 0; goto out; } /* Ok, we have to move this entire file to the next free block. */ phys = info->si_lf_eblk + 1; if (phys + block >= info->si_blocks) { err = -ENOSPC; goto out; } if (bi->i_sblock) { err = bfs_move_blocks(inode->i_sb, bi->i_sblock, bi->i_eblock, phys); if (err) { dprintf("failed to move ino=%08lx -> fs corruption\n", inode->i_ino); goto out; } } else err = 0; dprintf("c=%d, b=%08lx, phys=%08lx (moved)\n", create, (unsigned long)block, phys); bi->i_sblock = phys; phys += block; info->si_lf_eblk = bi->i_eblock = phys; /* * This assumes nothing can write the inode back while we are here * and thus update inode->i_blocks! (XXX) */ info->si_freeb -= bi->i_eblock - bi->i_sblock + 1 - inode->i_blocks; mark_inode_dirty(inode); map_bh(bh_result, sb, phys); out: mutex_unlock(&info->bfs_lock); return err; } static int bfs_writepage(struct page *page, struct writeback_control *wbc) { return block_write_full_page(page, bfs_get_block, wbc); } static int bfs_readpage(struct file *file, struct page *page) { return block_read_full_page(page, bfs_get_block); } static void bfs_write_failed(struct address_space *mapping, loff_t to) { struct inode *inode = mapping->host; if (to > inode->i_size) truncate_pagecache(inode, inode->i_size); } static int bfs_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { int ret; ret = block_write_begin(mapping, pos, len, flags, pagep, bfs_get_block); if (unlikely(ret)) bfs_write_failed(mapping, pos + len); return ret; } static sector_t bfs_bmap(struct address_space *mapping, sector_t block) { return generic_block_bmap(mapping, block, bfs_get_block); } const struct address_space_operations bfs_aops = { .readpage = bfs_readpage, .writepage = bfs_writepage, .write_begin = bfs_write_begin, .write_end = generic_write_end, .bmap = bfs_bmap, }; const struct inode_operations bfs_file_inops; d class='ctrl'>
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2017-02-03 17:10:28 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-08 23:36:29 +1100
commitd7df2443cd5f67fc6ee7c05a88e4996e8177f91b (patch)
tree098a7c0ca4fceb8a65cb1f693c9d71990388933d /sound/soc/au1x/ac97c.c
parenta0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'sound/soc/au1x/ac97c.c')