kernel/linux.git/drivers/mtd/ubi/build.c, branch linux-7.0.y

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

ubi: Add a check for ubi_num

2025-01-18T14:22:04+00:00

Added a check for ubi_num for negative numbers If the variable ubi_num takes negative values then we get: qemu-system-arm ... -append "ubi.mtd=0,0,0,-22222345" ... [ 0.745065] ubi_attach_mtd_dev from ubi_init+0x178/0x218 [ 0.745230] ubi_init from do_one_initcall+0x70/0x1ac [ 0.745344] do_one_initcall from kernel_init_freeable+0x198/0x224 [ 0.745474] kernel_init_freeable from kernel_init+0x18/0x134 [ 0.745600] kernel_init from ret_from_fork+0x14/0x28 [ 0.745727] Exception stack(0x90015fb0 to 0x90015ff8) Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 83ff59a06663 ("UBI: support ubi_num on mtd.ubi command line") Cc: stable@vger.kernel.org Signed-off-by: Denis Arefev Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger

mtd: ubi: Restore missing cleanup on ubi_init() failure path

2024-07-12T19:43:09+00:00

We need to clean-up debugfs and ubiblock if we fail after initialising them. Signed-off-by: Ben Hutchings Fixes: 927c145208b0 ("mtd: ubi: attach from device tree") Signed-off-by: Richard Weinberger

mtd: ubi: make ubi_class constant

2024-07-12T17:45:09+00:00

Since commit 43a7206b0963 ("driver core: class: make class_register() take a const *"), the driver core allows for struct class to be in read-only memory, so move the ubi_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: Greg Kroah-Hartman Suggested-by: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Reviewed-by: Zhihao Cheng Reviewed-by: Miquel Raynal Signed-off-by: Richard Weinberger

mtd: ubi: introduce pre-removal notification for UBI volumes

2024-02-25T21:41:33+00:00

Introduce a new notification type UBI_VOLUME_SHUTDOWN to inform users that a volume is just about to be removed. This is needed because users (such as the NVMEM subsystem) expect that at the time their removal function is called, the parenting device is still available (for removal of sysfs nodes, for example, in case of NVMEM which otherwise WARNs on volume removal). Signed-off-by: Daniel Golle Signed-off-by: Richard Weinberger

mtd: ubi: attach from device tree

2024-02-25T21:41:33+00:00

Introduce device tree compatible 'linux,ubi' and attach compatible MTD devices using the MTD add notifier. This is needed for a UBI device to be available early at boot (and not only after late_initcall), so volumes on them can be used eg. as NVMEM providers for other drivers. Signed-off-by: Daniel Golle Signed-off-by: Richard Weinberger

ubi: fastmap: Add module parameter to control reserving filling pool PEBs

2023-10-28T21:15:44+00:00

Adding 6th module parameter in 'mtd=xxx' to control whether or not reserving PEBs for filling pool/wl_pool. Signed-off-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: fastmap: Fix lapsed wear leveling for first 64 PEBs

2023-10-28T21:14:55+00:00

The anchor PEB must be picked from first 64 PEBs, these PEBs could have large erase counter greater than other PEBs especially when free space is nearly running out. The ubi_update_fastmap will be called as long as pool/wl_pool is empty, old anchor PEB is erased when updating fastmap. Given an UBI device with N PEBs, free PEBs is nearly running out and pool will be filled with 1 PEB every time ubi_update_fastmap invoked. So t=N/POOL_SIZE[1]/64 means that in worst case the erase counter of first 64 PEBs is t times greater than other PEBs in theory. After running fsstress for 24h, the erase counter statistics for two UBI devices shown as follow(CONFIG_MTD_UBI_WL_THRESHOLD=128): Device A(1024 PEBs, pool=50, wl_pool=25): ========================================================= from to count min avg max --------------------------------------------------------- 0 .. 9: 0 0 0 0 10 .. 99: 0 0 0 0 100 .. 999: 0 0 0 0 1000 .. 9999: 0 0 0 0 10000 .. 99999: 960 29224 29282 29362 100000 .. inf: 64 117897 117934 117940 --------------------------------------------------------- Total : 1024 29224 34822 117940 Device B(8192 PEBs, pool=256, wl_pool=128): ========================================================= from to count min avg max --------------------------------------------------------- 0 .. 9: 0 0 0 0 10 .. 99: 0 0 0 0 100 .. 999: 0 0 0 0 1000 .. 9999: 8128 2253 2321 2387 10000 .. 99999: 64 35387 35387 35388 100000 .. inf: 0 0 0 0 --------------------------------------------------------- Total : 8192 2253 2579 35388 The key point is reducing fastmap updating frequency by enlarging POOL_SIZE, so let UBI reserve ubi->fm_pool.max_size PEBs during attaching. Then POOL_SIZE will become ubi->fm_pool.max_size/2 even in free space running out case. Given an UBI device with 8192 PEBs(16384\8192\4096 is common large-capacity flash), t=8192/128/64=1. The fastmap updating will happen in either wl_pool or pool is empty, so setting fm_pool_rsv_cnt as ubi->fm_pool.max_size can fill wl_pool in full state. After pool reservation, running fsstress for 24h: Device A(1024 PEBs, pool=50, wl_pool=25): ========================================================= from to count min avg max --------------------------------------------------------- 0 .. 9: 0 0 0 0 10 .. 99: 0 0 0 0 100 .. 999: 0 0 0 0 1000 .. 9999: 0 0 0 0 10000 .. 99999: 1024 33801 33997 34056 100000 .. inf: 0 0 0 0 --------------------------------------------------------- Total : 1024 33801 33997 34056 Device B(8192 PEBs, pool=256, wl_pool=128): ========================================================= from to count min avg max --------------------------------------------------------- 0 .. 9: 0 0 0 0 10 .. 99: 0 0 0 0 100 .. 999: 0 0 0 0 1000 .. 9999: 8192 2205 2397 2460 10000 .. 99999: 0 0 0 0 100000 .. inf: 0 0 0 0 --------------------------------------------------------- Total : 8192 2205 2397 2460 The difference of erase counter between first 64 PEBs and others is under WL_FREE_MAX_DIFF(2*UBI_WL_THRESHOLD=2*128=256). Device A: 34056 - 33801 = 255 Device B: 2460 - 2205 = 255 Next patch will add a switch to control whether UBI needs to reserve PEBs for filling pool. Fixes: dbb7d2a88d2a ("UBI: Add fastmap core") Link: https://bugzilla.kernel.org/show_bug.cgi?id=217787 Signed-off-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: Refuse attaching if mtd's erasesize is 0

2023-09-07T19:59:04+00:00

There exists mtd devices with zero erasesize, which will trigger a divide-by-zero exception while attaching ubi device. Fix it by refusing attaching if mtd's erasesize is 0. Fixes: 801c135ce73d ("UBI: Unsorted Block Images") Reported-by: Yu Hao Link: https://lore.kernel.org/lkml/977347543.226888.1682011999468.JavaMail.zimbra@nod.at/T/ Signed-off-by: Zhihao Cheng Reviewed-by: Miquel Raynal Signed-off-by: Richard Weinberger