summaryrefslogtreecommitdiff
path: root/include/scsi/scsi_eh.h
blob: 98d366b5577069201815ac77e0827fa6f32f664b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
#ifndef _SCSI_SCSI_EH_H
#define _SCSI_SCSI_EH_H

#include <linux/scatterlist.h>

#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_common.h>
struct scsi_device;
struct Scsi_Host;

extern void scsi_eh_finish_cmd(struct scsi_cmnd *scmd,
			       struct list_head *done_q);
extern void scsi_eh_flush_done_q(struct list_head *done_q);
extern void scsi_report_bus_reset(struct Scsi_Host *, int);
extern void scsi_report_device_reset(struct Scsi_Host *, int, int);
extern int scsi_block_when_processing_errors(struct scsi_device *);
extern bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
					 struct scsi_sense_hdr *sshdr);
extern int scsi_check_sense(struct scsi_cmnd *);

static inline bool scsi_sense_is_deferred(const struct scsi_sense_hdr *sshdr)
{
	return ((sshdr->response_code >= 0x70) && (sshdr->response_code & 1));
}

extern int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,
				   u64 * info_out);

extern int scsi_ioctl_reset(struct scsi_device *, int __user *);

struct scsi_eh_save {
	/* saved state */
	int result;
	enum dma_data_direction data_direction;
	unsigned underflow;
	unsigned char cmd_len;
	unsigned char prot_op;
	unsigned char *cmnd;
	struct scsi_data_buffer sdb;
	struct request *next_rq;
	/* new command support */
	unsigned char eh_cmnd[BLK_MAX_CDB];
	struct scatterlist sense_sgl;
};

extern void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd,
		struct scsi_eh_save *ses, unsigned char *cmnd,
		int cmnd_size, unsigned sense_bytes);

extern void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd,
		struct scsi_eh_save *ses);

#endif /* _SCSI_SCSI_EH_H */
self is unlinked by the shrinker, its deletion from the tree can cause the left-most leaf node in the tree to be shrunk. If that happens to be a shadow node as well, we don't unlink it from the LRU as we should. Consider this tree, where the s are shadow entries: root->rnode | [0 n] | | [s ] [sssss] Now the shadow node shrinker reclaims the rightmost leaf node through the shadow node LRU: root->rnode | [0 ] | [s ] Because the parent of the deleted node is the first level below the root and has only one child in the left-most slot, the intermediate level is shrunk and the node containing the single shadow is put in its place: root->rnode | [s ] The shrinker again sees a single left-most slot in a first level node and thus decides to store the shadow in root->rnode directly and free the node - which is a leaf node on the shadow node LRU. root->rnode | s Without the update callback, the freed node remains on the shadow LRU, where it causes later shrinker runs to crash. Pass the node updater callback into __radix_tree_delete_node() in case the deletion causes the left-most branch in the tree to collapse too. Also add warnings when linked nodes are freed right away, rather than wait for the use-after-free when the list is scanned much later. Fixes: 14b468791fa9 ("mm: workingset: move shadow entry tracking to radix tree exceptional tracking") Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Hugh Dickins <hughd@google.com> Reported-by: Andrea Arcangeli <aarcange@redhat.com> Reported-and-tested-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Chris Leech <cleech@redhat.com> Cc: Lee Duncan <lduncan@suse.com> Cc: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'net/ax25')