#include #include #include #include #include "omfs.h" unsigned long omfs_count_free(struct super_block *sb) { unsigned int i; unsigned long sum = 0; struct omfs_sb_info *sbi = OMFS_SB(sb); int nbits = sb->s_blocksize * 8; for (i = 0; i < sbi->s_imap_size; i++) sum += nbits - bitmap_weight(sbi->s_imap[i], nbits); return sum; } /* * Counts the run of zero bits starting at bit up to max. * It handles the case where a run might spill over a buffer. * Called with bitmap lock. */ static int count_run(unsigned long **addr, int nbits, int addrlen, int bit, int max) { int count = 0; int x; for (; addrlen > 0; addrlen--, addr++) { x = find_next_bit(*addr, nbits, bit); count += x - bit; if (x < nbits || count > max) return min(count, max); bit = 0; } return min(count, max); } /* * Sets or clears the run of count bits starting with bit. * Called with bitmap lock. */ static int set_run(struct super_block *sb, int map, int nbits, int bit, int count, int set) { int i; int err; struct buffer_head *bh; struct omfs_sb_info *sbi = OMFS_SB(sb); err = -ENOMEM; bh = sb_bread(sb, clus_to_blk(sbi, sbi->s_bitmap_ino) + map); if (!bh) goto out; for (i = 0; i < count; i++, bit++) { if (bit >= nbits) { bit = 0; map++; mark_buffer_dirty(bh); brelse(bh); bh = sb_bread(sb, clus_to_blk(sbi, sbi->s_bitmap_ino) + map); if (!bh) goto out; } if (set) { set_bit(bit, sbi->s_imap[map]); set_bit(bit, (unsigned long *)bh->b_data); } else { clear_bit(bit, sbi->s_imap[map]); clear_bit(bit, (unsigned long *)bh->b_data); } } mark_buffer_dirty(bh); brelse(bh); err = 0; out: return err; } /* * Tries to allocate exactly one block. Returns true if successful. */ int omfs_allocate_block(struct super_block *sb, u64 block) { struct buffer_head *bh; struct omfs_sb_info *sbi = OMFS_SB(sb); int bits_per_entry = 8 * sb->s_blocksize; unsigned int map, bit; int ret = 0; u64 tmp; tmp = block; bit = do_div(tmp, bits_per_entry); map = tmp; mutex_lock(&sbi->s_bitmap_lock); if (map >= sbi->s_imap_size || test_and_set_bit(bit, sbi->s_imap[map])) goto out; if (sbi->s_bitmap_ino > 0) { bh = sb_bread(sb, clus_to_blk(sbi, sbi->s_bitmap_ino) + map); if (!bh) goto out; set_bit(bit, (unsigned long *)bh->b_data); mark_buffer_dirty(bh); brelse(bh); } ret = 1; out: mutex_unlock(&sbi->s_bitmap_lock); return ret; } /* * Tries to allocate a set of blocks. The request size depends on the * type: for inodes, we must allocate sbi->s_mirrors blocks, and for file * blocks, we try to allocate sbi->s_clustersize, but can always get away * with just one block. */ int omfs_allocate_range(struct super_block *sb, int min_request, int max_request, u64 *return_block, int *return_size) { struct omfs_sb_info *sbi = OMFS_SB(sb); int bits_per_entry = 8 * sb->s_blocksize; int ret = 0; int i, run, bit; mutex_lock(&sbi->s_bitmap_lock); for (i = 0; i < sbi->s_imap_size; i++) { bit = 0; while (bit < bits_per_entry) { bit = find_next_zero_bit(sbi->s_imap[i], bits_per_entry, bit); if (bit == bits_per_entry) break; run = count_run(&sbi->s_imap[i], bits_per_entry, sbi->s_imap_size-i, bit, max_request); if (run >= min_request) goto found; bit += run; } } ret = -ENOSPC; goto out; found: *return_block = (u64) i * bits_per_entry + bit; *return_size = run; ret = set_run(sb, i, bits_per_entry, bit, run, 1); out: mutex_unlock(&sbi->s_bitmap_lock); return ret; } /* * Clears count bits starting at a given block. */ int omfs_clear_range(struct super_block *sb, u64 block, int count) { struct omfs_sb_info *sbi = OMFS_SB(sb); int bits_per_entry = 8 * sb->s_blocksize; u64 tmp; unsigned int map, bit; int ret; tmp = block; bit = do_div(tmp, bits_per_entry); map = tmp; if (map >= sbi->s_imap_size) return 0; mutex_lock(&sbi->s_bitmap_lock); ret = set_run(sb, map, bits_per_entry, bit, count, 0); mutex_unlock(&sbi->s_bitmap_lock); return ret; } r>space:mode:
authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /security/selinux/include/avc.h
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'security/selinux/include/avc.h')