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: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 12b25e5b7b81..248ff9e477e7 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -508,7 +508,7 @@ int ubi_wl_get_peb(struct ubi_device *ubi, int dtype)
         ubi_assert(dtype == UBI_LONGTERM || dtype == UBI_SHORTTERM ||
                    dtype == UBI_UNKNOWN);
 
-        pe = kmalloc(sizeof(struct ubi_wl_prot_entry), GFP_KERNEL);
+        pe = kmalloc(sizeof(struct ubi_wl_prot_entry), GFP_NOFS);
         if (!pe)
                 return -ENOMEM;
 
@@ -645,7 +645,7 @@ static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int tortur
         if (err > 0)
                 return -EINVAL;
 
-        ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+        ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS);
         if (!ec_hdr)
                 return -ENOMEM;
 
@@ -768,7 +768,7 @@ static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e,
         dbg_wl("schedule erasure of PEB %d, EC %d, torture %d",
                e->pnum, e->ec, torture);
 
-        wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_KERNEL);
+        wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS);
         if (!wl_wrk)
                 return -ENOMEM;
 
@@ -802,7 +802,7 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
         if (cancel)
                 return 0;
 
-        vid_hdr = ubi_zalloc_vid_hdr(ubi);
+        vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
         if (!vid_hdr)
                 return -ENOMEM;
 
@@ -1028,7 +1028,7 @@ static int ensure_wear_leveling(struct ubi_device *ubi)
         ubi->wl_scheduled = 1;
         spin_unlock(&ubi->wl_lock);
 
-        wrk = kmalloc(sizeof(struct ubi_work), GFP_KERNEL);
+        wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS);
         if (!wrk) {
                 err = -ENOMEM;
                 goto out_cancel;
@@ -1631,7 +1631,7 @@ static int paranoid_check_ec(const struct ubi_device *ubi, int pnum, int ec)
         long long read_ec;
         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;