Commit 33818bbb authored by Artem Bityutskiy's avatar Artem Bityutskiy
Browse files

UBI: allocate memory with GFP_NOFS 



Use GFP_NOFS flag when allocating memory on I/O path, because otherwise
we may deadlock the filesystem which works on top of us. We observed
the deadlocks with UBIFS. Example:

VFS->FS lock a lock->UBI->kmalloc()->VFS writeback->FS locks the same
lock again.

Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
parent ef6075fb

drivers/mtd/ubi/eba.c

+6 −6
Original line number Diff line number Diff line
@@ -157,7 +157,7 @@ static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id, 
{

	struct ltree_entry *le, *le1, *le_free;



	le = kmem_cache_alloc(ltree_slab, GFP_KERNEL);

	le = kmem_cache_alloc(ltree_slab, GFP_NOFS);

	if (!le)

		return ERR_PTR(-ENOMEM);
@@ -397,7 +397,7 @@ int ubi_eba_read_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf, 


retry:

	if (check) {

		vid_hdr = ubi_zalloc_vid_hdr(ubi);

		vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

		if (!vid_hdr) {

			err = -ENOMEM;

			goto out_unlock;
@@ -497,7 +497,7 @@ static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum, 
	struct ubi_vid_hdr *vid_hdr;

	unsigned char *new_buf;



	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

	if (!vid_hdr) {

		return -ENOMEM;

	}
@@ -627,7 +627,7 @@ int ubi_eba_write_leb(struct ubi_device *ubi, int vol_id, int lnum, 
	 * The logical eraseblock is not mapped. We have to get a free physical

	 * eraseblock and write the volume identifier header there first.

	 */

	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

	if (!vid_hdr) {

		leb_write_unlock(ubi, vol_id, lnum);

		return -ENOMEM;
@@ -738,7 +738,7 @@ int ubi_eba_write_leb_st(struct ubi_device *ubi, int vol_id, int lnum, 
	else

		ubi_assert(len % ubi->min_io_size == 0);



	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

	if (!vid_hdr)

		return -ENOMEM;
@@ -844,7 +844,7 @@ int ubi_eba_atomic_leb_change(struct ubi_device *ubi, int vol_id, int lnum, 
	if (ubi->ro_mode)

		return -EROFS;



	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

	if (!vid_hdr)

		return -ENOMEM;

drivers/mtd/ubi/io.c

+2 −2
Original line number Diff line number Diff line
@@ -1099,7 +1099,7 @@ static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum) 
	uint32_t crc, hdr_crc;

	struct ubi_ec_hdr *ec_hdr;



	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);

	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS);

	if (!ec_hdr)

		return -ENOMEM;
@@ -1179,7 +1179,7 @@ static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum) 
	struct ubi_vid_hdr *vid_hdr;

	void *p;



	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);

	if (!vid_hdr)

		return -ENOMEM;

drivers/mtd/ubi/scan.c

+2 −2
Original line number Diff line number Diff line
@@ -323,7 +323,7 @@ static int compare_lebs(const struct ubi_device *ubi, 
	} else {

		pnum = seb->pnum;



		vh = ubi_zalloc_vid_hdr(ubi);

		vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);

		if (!vh)

			return -ENOMEM;
@@ -948,7 +948,7 @@ struct ubi_scan_info *ubi_scan(struct ubi_device *ubi) 
	if (!ech)

		goto out_si;



	vidh = ubi_zalloc_vid_hdr(ubi);

	vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);

	if (!vidh)

		goto out_ech;

drivers/mtd/ubi/ubi.h

+4 −2
Original line number Diff line number Diff line
@@ -439,16 +439,18 @@ int ubi_io_write_vid_hdr(const struct ubi_device *ubi, int pnum, 
/**

 * ubi_zalloc_vid_hdr - allocate a volume identifier header object.

 * @ubi: UBI device description object

 * @gfp_flags: GFP flags to allocate with

 *

 * This function returns a pointer to the newly allocated and zero-filled

 * volume identifier header object in case of success and %NULL in case of

 * failure.

 */

static inline struct ubi_vid_hdr *ubi_zalloc_vid_hdr(const struct ubi_device *ubi)

static inline struct ubi_vid_hdr *

ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)

{

	void *vid_hdr;



	vid_hdr = kzalloc(ubi->vid_hdr_alsize, GFP_KERNEL);

	vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);

	if (!vid_hdr)

		return NULL;

drivers/mtd/ubi/vtbl.c

+1 −1
Original line number Diff line number Diff line
@@ -264,7 +264,7 @@ static int create_vtbl(const struct ubi_device *ubi, struct ubi_scan_info *si, 


	ubi_msg("create volume table (copy #%d)", copy + 1);



	vid_hdr = ubi_zalloc_vid_hdr(ubi);

	vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);

	if (!vid_hdr)

		return -ENOMEM;